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The present study aims to investigate the effect of different forms of chromium (inorganic chromium, chromium-methionine and chromium nanoparticles) on blood parameters, antioxidant status and immunoglobin of Afshar ewes during the transition period and lambs. They were done under the influence of heat stress. 40 pregnant Afshar ewes from 42 ± 2 days before the expected parturition in a completely randomized design. Four experimental treatments were assigned with ten replications. Experimental treatments include basic diet without chromium supplement (control), basic diet containing 3 mg of chromium in mineral form per kg of dry matter, basic diet containing 3 mg of chromium in the form of chromium-methionine per kg of dry matter and The basic diet contained 3 mg of chromium in the form of chromium nanoparticles per kilogram of dry matter. The results showed that the addition of different forms of chromium to the ewes' diet caused a significant increase in the concentration of red blood cells, hemoglobin and blood hematocrit compared to the control group (P<0.05). Adding chromium to the diet of ewes caused a significant decrease in white blood cells (P<0.05). In experimental treatments, no significant difference was observed in terms of platelets, average volume of red blood cells, average concentration of red blood cells, neutrophils, lymphocytes, monocytes, and eosinophils. The concentration of superoxide desmutase, glutathione peroxidase, catalase, triiodothyronine and tetraiodothyronine in the blood in the treatments receiving different forms of chromium also increased compared to the control group (P<0.05). The results showed that the concentration of malondialdehyde and total antioxidant capacity in ewes and lambs receiving chromium supplementation was lower than the control treatment (P<0.05). However, there was no significant difference between different experimental treatments in terms of ceruloplasmin concentration and the ratio of T4 to T3 (P<0.05). The concentration of IgG and IgM in lambs receiving different forms of chromium also increased compared to the control group (P<0.05). In general, the use of chromium, especially in the form of chromiummethionine and chromium nanoparticles, is recommended during the transition period of ewes under the influence of heat stress. [ABSTRACT FROM AUTHOR]

Introduction: Workers who work in warm situations need clothes with better thermal regulation. Nowadays, improving the thermal regulation properties of cotton fabric by treating it with phase change materials (PCMs) has been considered. The type of fabric plays an important role in providing thermal comfort. Cotton fabric is the most popular raw material in the textile industry due to its distinctive features. Therefore, this systematic review aims to investigate the effects of PCM nanoencapsulation in commonly used cotton fabrics, including morphology, thermal properties, thermal stability, tensile strength, abrasion resistance, leakage, water absorption, washing ability, and breathability of the fabric, related challenges, and future research trends. Material and Methods: This research was conducted with the papers obtained from the systematic search in Science Direct, Web of Sciences, Scopus, and PubMed databases. Keywords “nanoencapsulated phase change materials”, “nanoenhanced phase change materials”, “cotton”, “cotton fabric”, and “cotton textiles” were used. Results: Of the 1251 studies identified through search databases, 13 were selected according to the entry criteria. The results revealed that in all the studies, PCM nanocapsules were successfully synthesized and inserted into the cotton fabric, improving the fabric’s thermal properties. Most studies used in situ polymerization and mini-emulsion polymerization for nanoencapsulation. The pad-dry-cure method was also widely used for applying nanocapsules to cotton fabric. Conclusion: This systematic review showed that synthesized nanocapsules of phase change materials and applied them to cotton fabric can improve the thermoregulating properties of the fabric. It is suggested to expand the research to design thermoregulating clothes made from treated fabrics and investigate their cooling performance.

Introduction: The transition period between late pregnancy and early lactation (also called the periparturient period) certainly is the most interesting stage of the lactation cycle and is the last 3 weeks before parturition to 3 weeks after parturition. Most infectious diseases and metabolic disorders occur during this period. Milk fever, ketosis, retained fetal membranes, metritis, and displaced abomasum primarily impact cows during the periparturient period (Drackley 1999). Any nutritional limitation during this period has an important impact on cow efficiency and consequently, milk production decreases. Dairy cows encounter substantial metabolic and physiological adaptations during the transition period. The immune system during the periparturient period is impaired. At this time, the most important factor causing immune-suppression in highly productive cows is metabolic stress resulting from hormonal and metabolic fluctuations, a negative energy balance, shortage of proteins, minerals and vitamins which are required to meet the demands of the fetus as well as the onset of lactation (Sordillo 2016). In the world, Cu deficiency is one of the most common problems in cattle with clinical and subclinical signs (Hill and Shannon 2019). Even marginal Cu deficiency (6 to 7 ppm dietary Cu) depresses blood neutrophil function in dairy cattle (Torre et al. 1996). One strategy for improving immune system of transition dairy cows is mineral and vitamin supplementation. It has been reported that many minerals are enzymatic cofactors (Filappi et al. 2005). Studies showed that minerals injection would be a suitable method to improve mineral utilization, and this may be a promising alternative to improve animal performance (Collet et al. 2017). Furthermore, during this period, dairy cows need antioxidants to combat reactive oxygen species (ROS) which produce during oxidative stress. Vitamin C was identified as antioxidant and could help immune system to overcome ROS production. Hence, this experiment was aimed to study the effect of vitamin C and copper injection on the health status of transition dairy cows. Materials and Methods: The study was carried out in a commercial farm located in Kermanshah province of Iran. Cows were enrolled from June 22, until September 22. Temperature and humidity index (THI) was calculated. It was between 72-78. The experiment was performed with 40 multiparous (twenty; second parity and twenty; third and fourth parity) Holstein lactating dairy cows which divided into four groups (10 animals/ group) in a 2×2 factorial arrangement. All cows were offered a TMR diet. Experimental treatments consisted of control (injection of 7 ml of NaCl % 0.9), Cu (injection of 75 mg Cu per cow) Vitamin C (injection of 25 mg vitamin C solution/kg BW), and Vitamin C-Cu (simultaneous injection of 25 mg vitamin C solution/kg BW and 75 mg Cu/ cow). Solutions were injected on d 20 and 40 days before expected parturition, parturition day and day 20 of postpartum. Serum concentrations of total protein, glucose, triglycerides, cholesterol, HDLcholesterol, Ca, P and Mg were determined using autoanalyzer by Pars Azmoon Kits. Serum concentrations of Beta hydroxybutyrate (BHBA) and non-esterified fatty acids (NEFA) were measured using autoanalyzer by Randow Kits. Serum concentration of Cu was determined by atomic absorbtion. Serum concentrations of vitamin C and superoxide dismutase was measured by Elisa reader. Incidence of metabolic disorders and infection disease were recorded. Data of serum variables were analyzed based on a randomized block design with a 2×2 (Vitamin C and Cu, with or without injection) factorial arrangement using Proc Mix of SAS software. The differences among treatments were evaluated using Tukey adjustment when the overall F-test was P ≤ 0.05. Trends were declared when 0.05 < P < 0.10. In addition, percentages of metabolic disorders were reported. Results and Discussion: Results showed that the interaction effect of vitamin C and Cu had no significant effect on serum concentration of vitamin C and superoxide dismutase activity. Cows received vitamin C had the greatest serum vitamin C concentration on d 20 prepartum, parturition day, d 10, 20 and 30 postpartum (P<0.05). Content of serum Cu were affected by the interaction of vitamin C and Cu on d 10 and d 20 postpartum (P<0.05). Copper injection increased serum Cu concentration and superoxide dismutase activity on d 20 prepartum, parturition day, d 10, 20 and 30 postpartum (P<0.05) in cows received Cu without vitamin C. Serum concentrations of P, Mg, glucose, BHBA, NEFA, triglycerides and HDL-cholesterol were not influenced by the interaction effect of vitamin C and Cu. Serum triglyceride concentration tended to decrease (P=0.06) in cows received vitamin C and on parturition day. Copper injection tended to increase (P=0.06) serum triglyceride concentration on d 20 postpartum. Serum protein concentration tended to decrease (P=0.07) in cows received vitamin C and in compared to other treatments on parturition day. Copper or vitamin C injections had no effect on serum concentrations of Ca, P, Mg, glucose, BHB and NEFA of experimental cows. Serum calcium concentration tended to increase (P=0.07) in cows received simultaneous injection of vitamin C and Cu in compared to the others on parturition day. Simultaneous injection of vitamin C and Cu tended to increase total cholesterol concentration (P=0.06) on d 10 and 30 of postpartum. Copper injection tended to increase total cholesterol concentration on d 20 prepartum, parturition day and d 10 postpartum (P=0.06). Control groups had the highest incidence rate of retained placenta and clinical mastitis. Conclusion: It is concluded that vitamin C and Cu injection reduced incidence rate of retained placenta and clinical mastitis due to improving immunity system performance of transition dairy cows. [ABSTRACT FROM AUTHOR]

Background: Rapid growth of broilers leads to insufficient cardiac output, cardiac hypertrophy, and finally sudden death. When livestock are exposed to hot environments, they often try to dissipate heat by increasing blood flow to the skin. This physiological response is a way for animals to adapt to long-term thermal conditions. However, this thermoregulatory mechanism has its limitations. While different animals have varying degrees of tolerance to heat stress, the cardiovascular system can only compensate within a certain range before it starts to impact food production. Domestic poultry, such as chickens, lack sweat glands, which is a key mechanism for body cooling in many other animals. This deficiency forces the cardiovascular system to work harder, sending more blood to the skin to help regulate body temperature. Broilers, in particular, have a narrow thermoneutral zone (the range of temperatures where an animal can maintain its body temperature without expending extra energy) and a high metabolic rate, which places an even greater burden on their cardiac function. Therefore, it is an appropriate model for studying cardiac disease. Heat stress is among the stressors affecting cardiac performance. In accordance with the cardiac system susceptibility of poultry to heat stress, especially broilers because of their fast growth rate, to enhance the ability of modern broiler chickens to withstand heat stress through selective breeding, we need to identify the crucial genes and biological processes that lead to unbalanced heart development and the high incidence of heat-induced heart problems. Thus, the aim was to consider the gene expression of cardiac contractility proteins under heat stress conditions during the growing period of broilers. Methods: Ross 708 broilers were subjected to heat stress (HS) of 35–37 °C for 8 hours daily for 21 days post-hatch. Initially, male broilers had unrestricted access to feed and water in spacious colony houses maintained at 33 °C, with the temperature gradually decreasing by 3 °C per week until it reached 24 °C by the day 21 post-hatch. At the conclusion of the growth period, the broilers were euthanized, and their left ventricles were isolated for mRNA extraction. RNA-seq data were obtained from NCBI’s with the accession number SRP082125. All the expressions of deferentially expressed genes (DEGs) were determined and analyzed by DAVID online bioinformatics tools. Gene ontology qualification, including biological processes (BP), cellular component (CC), and molecular role (MF), were achieved from DAVID. Heat stress induction was from days 21-42 for 8 hours every day for 21 days until to end of the growing period. Results: Gene expression changes were related to 35 genes of the muscular cardiocyte of the left ventricle. From seven genes related to the protein of troponin, TNN and TNNI1 genes, declined significantly, with an increase in the TNNT3 gene expression (P< 0.05). Of five genes related to the tropomyosin protein, the TPM1 gene showed a significant increase in expression (P < 0.05). Of the two genes related to the ryanodine receptor, RYR3 had significant gene upregulation (P < 0.05). From the ten genes related to DHPR, only CACNA2D2 had significant downregulation (P < 0.05). Among four calmodulin-related genes, CAMKK1 and CAMK1D showed significant downregulation, and CAMSAP2 revealed upregulation (P< 0.05). Significant reductions occurred in the expression of five associated genes of heavy-chain myosin (P< 0.05). Conclusion: Heat stress reduced gene expression of ryanodine, DHPR, and troponin, those related to calcium release into the cell cytosol. Furthermore, it prevents cardiac hypertrophy by decreasing the expression of genes related to the heavy chain of myosin. Thus, the vulnerability of modern broilers to heart problems, when exposed to high temperatures, may be linked to their heart's reduced capacity, which is likely due to their relatively smaller heart size. According to genetic analysis, the smaller heart size in broilers under heat stress than those in a comfortable temperature environment is likely caused by slower cell growth and division. This research identifies specific genes and biological pathways that could be targeted through breeding to develop broilers that are more resistant to heat stress and have healthier hearts. This study has identified specific genes and biological processes linked to the reduction in heart size observed in broiler chickens subjected to heat stress. These insights provide new opportunities for developing targeted breeding strategies to address this issue. The findings indicate that selective breeding, by focusing on the identified genes and pathways, may enable the development of broiler chickens that are more resistant to heat stress and have healthier hearts. By concentrating on these genetic factors, breeders can work toward creating broiler populations that are more resilient to high temperatures and less susceptible to heart problems. [ABSTRACT FROM AUTHOR]

Background: Using genetic enhancement techniques has led to the development of poultry capable of fulfilling significant portions of human dietary requirements through meat and egg production. Maximizing genetic potential necessitates the provision of conducive environmental conditions. Heat stress poses a substantial challenge within the poultry sector, detrimentally impacting poultry production and growth, there by diminishing breeders' economic returns. Adaptation to heat stress is contingent upon a multitude of factors. The capacity to establish homeostasis through alterations in gene expression serves to mitigate extracellular damage and restore physiological equilibrium upon reversion to favorable temperature ranges. Domestic birds thrive within a temperature spectrum of 18-24 °C, with any deviation beyond this range precipitating elevated mortality rates. Elevated mortality is attributed to heat-induced suppression of the immune system and compromised resilience. Moreover, heat stress amplifies the secretion of the corticotropin-releasing hormone, subsequently elevating blood corticosterone levels, thereby instigating molecular alterations under stress conditions. Hence, a comprehensive examination of this challenge from diverse perspectives holds significant promise. Consequently, the present study endeavors to delineate protein complexes and pivotal signaling pathways regulated by distinct genes expressed in response to heat stress within the hypothalamus of broiler chickens. Methods: The systemic response of chickens' hypothalamus transcripts to heat stress was comprehensively examined in this investigation. Transcript expression profiles from eight chicken hypothalamus tissues, including four subjected to thermal stress and four under non-stress conditions, were retrieved from the GEO database (accession number GSE37400). The raw microarray data underwent rigorous quality control measures and normalization using GEO2R software to ensure reliability and consistency. Genes with discernible expression changes were identified based on a stringent criterion of P-value > 0.05 and (LogFC < 0.5-0.5). Subsequently, a gene expression regulatory network was constructed to elucidate the interplay among genes implicated in broiler heat stress, employing Cytoscape software in conjunction with the STRING database. The network visualization facilitated the identification of protein clusters, representing areas of high density, which were further analyzed using the CytoCluster plugin renowned for its efficacy in detecting such densely interconnected regions. Following the delineation and characterization of genes within these clusters, the DAVID database was utilized to elucidate the relevant biological pathways associated with the identified genes. This comprehensive approach enabled a detailed exploration of the molecular mechanisms underlying the hypothalamic response to heat stress in chickens. Results: The analysis of microarray data unveiled a comprehensive portrait of the molecular response to heat stress in chickens. Among the 43,607 initially examined probes, 593 differentially expressed genes were identified after rigorous curation involving the elimination of duplicate genes and application of a significance threshold. A network encompassing 149 genes with a minimum interaction score of 0.4 was constructed utilizing the STRING software, shedding light on the intricate interplay among these genes. Subsequent investigations honed in on genes exerting significant regulatory effects in response to heat stress, elucidating their pivotal roles in orchestrating physiological processes. Functional assessment of the networked genes revealed their involvement in diverse biological activities, including the positive regulation of T cell- mediated immunity, WNT and MAPK signaling pathways, as well as phagocytosis and natural killer (NK) cell activity. Particularly noteworthy was the observation of suppressed NK cell activity in broilers under heat stress, likely influenced by heightened corticosterone levels and subsequent inhibition of thyroid hormone secretion, thereby impacting temperature regulation and metabolism. Moreover, the elevation in blood glucose levels observed in stressed chicks may contribute to their adaptive survival response. Importantly, heat stress was observed to disrupt cellular homeostasis and molecular pathways, manifesting in alterations in biological processes such as the cell cycle. This disruption in the cell cycle may signify a novel mechanism of stress resistance in vertebrates, further underscoring the complexity of the physiological response to thermal stress in chickens. Conclusion: The analysis of gene functionality within the network underscores the intricate nature of the innate immune response and cellular demise elicited by heat stress. Notably, certain genes identified in this analysis participate in positively regulating T cell-mediated immunity, vascular endothelial growth factor (VEGF), WNT signaling, and mitogen-activated protein kinase (MAPK) pathways. Introducing a biomarker panel comprising genes, such as MAPK14, NT3, SOX2, YAP1, FGF2, LRRK1, LEF1, and TLE1, holds promise for advancing our understanding of the underlying molecular mechanisms governing stress responses in poultry. Furthermore, this approach may facilitate the discovery of novel genes whose modulation could mitigate the effects of thermal stress. [ABSTRACT FROM AUTHOR]

Introduction: During the time around parturition, animals make many metabolic adjustments to support the transition from pregnancy to lactation. Before giving birth, animals are subjected to a lot of metabolic effects, to prepare the physiological conditions of the body in the time after giving birth and during lactation. In addition, dairy cattle produce milk more than their ability to consume energy, as a result, they are in a negative energy balance at the beginning of lactation, which may reduce the longevity of the cattle in the herd and increase the rate of elimination of dairy cattle. Heat stress in late pregnancy is aggravated by energy restriction. In such conditions, the use of management and nutritional methods will reduce the problems during the transfer period and heat stress. One of the ways to optimize the productive and reproductive conditions of livestock, through improving the metabolism of nutrients and eliminating or reducing stress conditions, is to use chromium as a metabolic improver. According to scientific sources, the chromium requirement for sheep is three to five mg per day, and for dairy cows is 15 to 50 mg per day. Inorganic chromium has a bioavailability of about 0.5%. Organic chromium has more than 25% intestinal absorption, and therefore, consumption of inorganic chromium is not recommended due to its low bioavailability and toxic effects. Among the sources of organic chromium, chromium-methionine has been recognized by important global food and drug organizations as a compound with high bioavailability, impressive metabolic responses, and no toxicity complications. This experiment was conducted to investigate the effect of using different forms of chromium around calving on feed consumption, nutrient digestibility, nutritional behavior of Afshari ewes, and the performance of their lambs under the influence of heat stress. Materials and methods: Forty pregnant Afshari ewes were assigned to four experimental treatments with 10 replicates from 42±5 days before the expected birth in a completely randomized design. Experimental treatments include 1) a basic diet without chromium supplementation (control), 2) a basic diet containing three mg of chromium in mineral form per kg of dry matter, 3) a basic diet containing three mg of chromium in the form of chromium-methionine per kg of dry matter, and 4) a basic diet contained three mg of chromium in the form of chromium nanoparticles per kilogram of dry matter. The length of the test period was 84 days. Weighing of ewes was done at the beginning, at the time of calving, and the end of the period. The rest of the feed is weighed every day and the daily feed consumption was calculated by deducting from the provided feed. Sampling of the rumen fluid was done on the 14th day after birth. The rumen fluid was taken before feeding in the morning (zero hour), and at three and six hours after feeding by esophageal tube, then the pH amount of rumen contents was measured and recorded immediately after extraction by a mobile digital pH meter (Metrohm laboratory pH meter-691) which was calibrated at the same place. To measure rumen liquid ammonia nitrogen, samples were used three hours after morning feeding. To measure the concentration of volatile fatty acids, five mL of rumen fluid samples were prepared and 1 mL of metaphosphoric acid 25% was added to them and kept at -20ºC until the experiment. On the 10th day after birth, blood samples were taken from the jugular vein of ewes and lambs three hours after morning feeding. To measure blood metabolites including glucose, insulin, cholesterol, triglyceride, urea, creatinine, total protein, albumin, and globulin, Pars Azmoun chemical kits and auto-analyzer (Spain BT 3500) were used. Results and discussion: The results showed that, from the third to the sixth weeks after birth, dry matter consumption in ewes receiving chromium-methionine and chromium nanoparticles had an upward trend compared to the other two treatments (P<0.05). The addition of chromium to the diet of ewes had no significant effect on rumen pH, volatile fatty acids, and rumen ammonia nitrogen concentration. The addition of chromium supplement to the diet of ewes caused a significant decrease in the rumen protozoa population compared to the control group (P<0.05). Adding different forms of chromium to the diet of sheep caused a decrease in glucose concentration, and an increase in chromium, insulin, total protein, albumin, and serum globulin compared to the control group (P<0.05). No significant difference was observed between experimental treatments on blood cholesterol, triglyceride, urea, and creatinine concentrations. Also, different forms of chromium did not have a significant effect on the blood parameters of the born lambs. Conclusions: In general, the use of chromium, especially in the form of chromium-methionine and chromium nanoparticles, is recommended during the transfer phase of sheep under the influence of heat stress. [ABSTRACT FROM AUTHOR]

IntroductionGrasses are narrow-leaved plants that are used as cover plants in landscape. These plants are one of the basic and necessary components of the green cover of most gardens, parks and as the background color of landscape. In Iran, due to the high costs of planting and management of grass, high water requirements, climatic incompatibility and damage to water and soil salinity, it is recommended to remove from the green space in some cities, especially in areas with low water and water and soil saline. If it is possible to benefit from the role and influence of these plants by observing the technical points and choosing the best species for each area. Salinity stress is the second limiting factor for the growth of plants in the world after drought, which affects the efficiency and performance of plants. Increase in salinity causes a decrease in the water potential in the soil. In this condition, the plant spends most of its energy to maintain the water potential, cell mass, and water absorption to have minimal growth. The aim of this research is the effect of external application of glycine betaine on the accumulation of osmolality compounds and the antioxidant system of sports grass under salt stress. Materials and MethodsThis research was done in factorial form in completely randomized design with 3 replications on Rashid variety cucumber. The factors included 4 levels of temperature (25, 30, 35 and 40 degrees Celsius) and 3 levels of salicylic acid (0, 0.5 and 1 mM). When the seedlings reached the two-leaf stage, they were sprayed with different concentrations of salicylic acid two times with an interval of five days. One week after the application of salicylic acid, temperature treatment was gradually applied. After applying each heat treatment, the corresponding pots were transferred to the greenhouse with a temperature of 25 degrees Celsius. Then, fresh and dry weight of root and shoot, leaf surface, chlorophyll index, electrolyte leakage, proline, polyphenol oxidase enzyme activity and superoxide dismutase enzyme activity were measured. Results and Discussion The results showed that salinity stress decreased all the study morphological, physiological and biochemical parameters including plant height, shoot fresh and dry weight, number of tiller, leaf area, chlorophyll content, protein and total antioxidant capacity in the studied plants. It also increased peroxidase enzyme, H2O2 and proline in plants, but glycine betaine application significantly improved the morpho-physiological characteristics of plants compared to the control under salt stress conditions. Thus, the highest height, shoot fresh and dry weight, leaf area, number of tiller, chlorophyll content, and protein and antioxidant capacity were observed in plants sprayed with glycine betaine. Also, the highest content of glycine betaine and activity of catalase and peroxidase enzymes and the lowest content of glycine betaine and H2O2 were observed in in plants sprayed with glycine betaine and 10 mM glycine betaine was more effective than 5 mM. The occurrence of salinity in plants disrupts the absorption of ions and causes the reduction of nutrients and increases sodium ions. One of the effects of salinity in plants is the reduction of photosynthetic activity, which results in the reduction of chlorophyll, carbon dioxide absorption, photosynthetic capacity, plant height, shoot fresh and dry weight, number of tiller and leaf area. One of the most strategies to deal with stress is accumulation of osmolyte and increasing the antioxidant activity, which makes plants resistant to environmental stresses. Salinity, through the toxic effect of Na+ and Cl- ions, affects the growth and performance of the plant by reducing the soil water potential, disrupting water absorption and imbalance of nutrients in the plant. The results obtained from comparing the average results of glycine betaine show that glycine betaine increased plant height, shoot fresh and dry weight, number of tiller, leaf area, chlorophyll content, total protein and antioxidant capacity, but on the other hand, it increased proline and H2O2 decreased, which is due to the accumulation of glycine betaine as a protector in plants under salt stress conditions. In stress conditions, glycine betaine can protect photosynthetic activities including photosynthetic enzymes, proteins and lipids in thylakoid membranes in the combination of photosystem II, and also the task of protecting cell membranes against osmotic stresses in the plant. ConclusionThe results obtained from this research showed that salinity stress reduced all the morphological, physiological and biochemical characteristics in the sport grass plants, but glycine betaine application played a positive role in reducing salinity damage and maintaining plant quality. Glycine betaine is known as one of the effective molecules in stress signaling, so it can protect the plant cells against stress by reducing the destruction of the membrane and by increasing the salt tolerance mechanisms. Also, glycine betaine 10 mM is introduced as the best treatment to reduce salinity damage in sport grass during present study.

Introduction: The Japanese quail is a species known for its short production period and high productivity. Due to their small size and low feed requirements, they are considered a cost-effective option for egg production compared to other poultry species. Additionally, quail eggs are recognized for their superior nutritional value compared to regular chicken eggs. However, there is a need for effective methods to enhance productivity, especially in stressful situations. Previous research has indicated that the use of certain dietary supplements can address this issue and improve the productive traits of birds. Therefore, there is considerable scientific interest in studying the effects of natural compounds such as black seed and L-carnitine on the productive performance of laying Japanese quails, both under normal conditions and during heat stress. Investigating these factors can provide valuable insights into the development of strategies to effectively manage and optimize egg production in laying Japanese quails. This, in turn, would contribute to the sustainability and profitability of the poultry industry. In this study, we aimed to examine the effects of black seed, L-carnitine, and vitamin E on the productive performance, carcass characteristics, blood biochemical parameters, and immune responses of Japanese laying quails.Materials and Methods: A total of 500 Japanese laying quails were included in this study. They were divided into two temperature conditions: normal temperature and high temperature (36 degrees Celsius for 6 hours per day). Additionally, there were five experimental treatments: control diet (without any additives), black seed (1.5% black seed diet), L-carnitine (250 ppm + control diet), 1.5% black seed + 250 ppm L-carnitine diet, and Vitamin E diet (200 ppm + control diet). This resulted in a 5x2 factorial experiment with a total of 10 treatments, 5 replications, and 10 quails per replication. The study consisted of three phases: an adaptation period to the experimental diets lasting two weeks, exposure to the designated temperature conditions for five weeks, and a three-week recovery period. During these phases, various parameters were measured and recorded, including productive performance, carcass characteristics, and blood biochemical and immune indicators (such as triglyceride, cholesterol, LDL, HDL concentrations, heterophil, and lymphocyte percentages) under both heat stress and recovery periods in Japanese laying quails. Data analysis was performed using the Generalized Linear Model (GLM) method with the assistance of SAS software. Mean comparisons were conducted using Tukey's multiple range tests.Results and Discussion: The results of this study revealed several important findings. During the initial two weeks of the experiment, the consumption of feed containing black seed + L-carnitine led to the highest feed intake, while diets containing black seed, black seed + L-carnitine, and vitamin E demonstrated the highest egg mass compared to the control group (P

Introduction: Heat stress is the most physically harmful factor in open and closed industrial environments. It affects people's cognitive and mental functions, causes the speed of fatigue, reduces concentration and skill, and increases the amount of errors. Therefore, the current research has The Effect of Heat Stress Exposure on Visual- Auditory Performances of subjects in laboratory conditions. Materials and methods: This study was conducted on 32 male students of Shahid Beheshti University of Medical Sciences, aged 20 to 29, who were selected according to the condition of consent and meeting the inclusion criteria. Environmental heat stress was applied at three levels of temperature index of 22, 29, and 34 degrees Celsius, and the temperature index of 22 degrees Celsius was considered as the laboratory background condition. Then, they were studied in different laboratory conditions, including exposure to heat stress. The subjects' attention level and reaction time were evaluated using the Integrated Visual and Auditory Continues test tool. The participants completed the written consent form, demographic information form, and general health questionnaire. Also, the subjects' heart rate was recorded with a digital heart rate monitor. Results: This study showed that the amount of visual and auditory attention decreased significantly (p

Introduction: The Japanese quail is a species known for its short production faiod and high productivity. Due to their small size and low feed requirements, they are considered a cost-effective option for egg production compared to other poultry species. Additionally, quail eggs are recognized for their sufaior nutritional value compared to regular chicken eggs. However, there is a need for effective methods to enhance productivity, especially in stressful situations. Previous research has indicated that the use of certain dietary supplements can address this issue and improve the productive traits of birds. Therefore, there is considerable scientific interest in studying the effects of natural compounds such as black seed and L-carnitine on the productive faformance of laying Japanese quails, both under normal conditions and during heat stress. Investigating these factors can provide valuable insights into the development of strategies to effectively manage and optimize egg production in laying Japanese quails. This, in turn, would contribute to the sustainability and profitability of the poultry industry. In this study, we aimed to examine the effects of black seed, L-carnitine, and vitamin E on the productive faformance, carcass characteristics, blood biochemical parameters, and immune responses of Japanese laying quails.Materials and Methods: A total of 500 Japanese laying quails were included in this study. They were divided into two temfaature conditions: normal temfaature and high temfaature (36 degrees Celsius for 6 hours fa day). Additionally, there were five exfaimental treatments: control diet (without any additives), black seed (1.5% black seed diet), L-carnitine (250 ppm + control diet), 1.5% black seed + 250 ppm L-carnitine diet, and Vitamin E diet (200 ppm + control diet). This resulted in a 5x2 factorial exfaiment with a total of 10 treatments, 5 replications, and 10 quails fa replication. The study consisted of three phases: an adaptation faiod to the exfaimental diets lasting two weeks, exposure to the designated temfaature conditions for five weeks, and a three-week recovery faiod. During these phases, various parameters were measured and recorded, including productive faformance, carcass characteristics, and blood biochemical and immune indicators (such as triglyceride, cholesterol, LDL, HDL concentrations, heterophil, and lymphocyte facentages) under both heat stress and recovery faiods in Japanese laying quails. Data analysis was faformed using the Generalized Linear Model (GLM) method with the assistance of SAS software. Mean comparisons were conducted using Tukey's multiple range tests.Results and Discussion: The results of this study revealed several important findings. During the initial two weeks of the exfaiment, the consumption of feed containing black seed + L-carnitine led to the highest feed intake, while diets containing black seed, black seed + L-carnitine, and vitamin E demonstrated the highest egg mass compared to the control group (P<0.05). During the heat stress faiod, high temfaatures caused a decrease in feed intake, egg weight, egg production, and egg mass. However, the consumption of feed containing black seed + L-carnitine resulted in increased feed intake, and diets containing black seed, black seed + L-carnitine, and vitamin E showed increased egg production and mass compared to the control group. Furthermore, vitamin E exhibited a better conversion coefficient (P<0.05). During the recovery faiod, high temfaatures led to a decrease in feed intake but an increase in bird body weight. The control group exhibited the lowest feed intake and body weight, whereas diets containing black seed, black seed + L-carnitine, and vitamin E demonstrated the highest egg production and egg mass compared to the control group. Birds fed diets with black seed and vitamin E exhibited a better conversion coefficient (P<0.05). Regarding carcass yield and relative liver weight, the effect of environmental temfaature and exfaimental treatments during both heat stress and recovery faiods was not significant. However, the consumption of black seed, L-carnitine, and vitamin E was found to increase carcass yield and relative heart weight. Additionally, high temfaatures increased the relative liver weight (P<0.05). Moreover, birds fed control and black seed diets at normal and high temfaatures exhibited higher blood cholesterol levels compared to other exfaimental treatments. In normal temfaature conditions and diets containing vitamin E and L-carnitine, a higher facentage of lymphocytes was observed in the blood. In high temfaature conditions and diets containing L-carnitine and vitamin E, the heterophil to lymphocyte ratio was also higher (P<0.05).Conclusion: Finally, the findings of this study highlight the beneficial effects of incorporating black seed, L-carnitine, and vitamin E into the diet of Japanese laying quails, both under normal and high-temfaature conditions. These dietary interventions have shown positive impacts on the faformance of the quails. Consequently, these results can serve as valuable guidance for quail breeders and producers in selecting suitable feed regimens to manage heat stress in Japanese quail layers, thereby enhancing faformance efficiency, carcass characteristics, and blood lipid and immune parameters. [ABSTRACT FROM AUTHOR]

Introduction: Heat stress as one of the most challenging environmental stresses can growth performance. Broilers are sensitive to heat stress due to the lack of sweat glands. The temperature range for most poultry species is between 16 and 26 degrees Celsius. Heat stress reduces welfare, growth performance, high mortality and large economic losses changes in carcass composition, lipid profile and lipolytic capacity are high under heat stress conditions because heat stress causes significant increases in catabolic and stress hormones (epinephrine, cortisol, and glucagon). Jestrbesk et al. (2017) reported that heat stress increases the activity of fatty acid synthetase (which converts malonyl-CoA to acyl-ACP and acyl-ACP to myristat or palmitate), acetyl cocarboxylase (which it converts acetyl-CoA to malonyl-CoA) and acyl-coasynthetase (which converts myristate to myristate-CoA and palmitate to palmitate-CoA). Liver and adipose tissue are rich in fatty acid synthase, but more than 90% of fatty acid is synthesized in the liver of broiler chickens, and adipose tissue is only responsible for storage (Ijiri et al. 2016). Heat stress, through the increase of lipoprotein lipase in adipose tissue of animals, increases the capacity to harvest and store intestinal and liver-derived triglyceride in adipose tissue (Lu et al. 2007). Material and methods: The present study was performed to investigate the effect of mild and chronic heat stress on growth performance, carcass traits, blood parameters, meat quality and relative expression of broiler fatty acid synthase and lipoprotein lipase genes. For this purpose, 150 one-day-old male broilers of Ross 308 strain in a completely randomized design with 3 treatments (normal temperature (according to the recommendation of Ross 308 strain), mild stress (27 °C) and chronic stress (32 °C), 5 replicates and 10 birds were kept in each replication from 1 to 42 days. The diet was based on corn and soybean meal and formulated according Ross (308) requirements for three period of starter (1-10 d), growth (11-24 d) and finisher (25-42 d) days. Body weight gain and feed intake was measured periodically and calculated during the whole experiment on a pen basis, and the feed conversion ratio was calculated subsequently. At day 42 of age, two birds per pen were randomly selected, weighed, and slaughtered. After slaughter, percentage of carcass, breast, thigh, abdominal fat, pancreas, liver, heart, bursa of fabricius and spleen were calculated as a ratio of the live weight. To determine the meat quality, 50g of left breast muscle was collected in plastic bags and stored at a negative temperature of 20°C. Meat quality parameters including water holding capacity, moisture, ash, pH, fat, protein, malondialdehyde and total antioxidant activity were measured. Data were analyzed using the general Linear Model procedures of SAS 9.1. When the analysis of variance was significant, Duncan's multiple-range test was used to separate the means. Statements of statistical significance were based on P<0.05. Results and discussion: The results showed that the weight gain of chicks under chronic heat stress in the final period (25 to 42 days) and the whole period (1 to 42 days) was lower than chickens under normal temperature (P <0.05). Exposure to chronic heat stress significantly increased the relative weight of abdominal fat, plasma glucose and triglycerides, and malondialdehyde of broiler breast meat (P <0.05).In agreement with the present result, El-Husseiny and Krieger (1980) also reported that the abdominal fat of broiler chickens under 32 degrees Celsius temperature was more than that of chickens raised at 22 degrees Celsius. Mujahid et al. (2007) stated that heat stress increases plasma levels of fatty acids, triglycerides and cholesterol. The increase of these parameters is probably due to the release of glucocorticoids and the movement of fats, especially triglycerides from the tissues. In agreement with the present result, Lu et al. (2017) reported an increase in the level of malondialdehyde in the breast meat of broilers exposed to chronic heat stress. Heat stress leads to the creation of oxidative stress by increasing the production of free radicals, and the oxidative stress created during heat stress causes an increase in the level of malondialdehyde in skeletal muscles (Vosough-Ghanbari et al. 2010). Chronic heat stress also increased the relative expression of broiler lipoprotein lipase gene in broiler chickens (P <0.05). The relative expression of fatty acid synthase gene also increased significantly in the liver of birds exposed to mild and chronic heat stress (P <0.05). Fatty acid synthase is the limiting enzyme in last step of the synthesis of long-chain fatty acids in animals and the catalysis of acetyl-CoA and malonyll-CoA to fatty acids (Smith 2003). Fatty acid synthesized by liver are incorporated into triacyllglycerols and transported as very low- density lipoproteins (VLDL), which provide this key energy source for other tissues for immediate use or provides storage (Flees et al. 2017). Studies suggest that under stress conditions, high levels of corticosterone and plasma insulin can increase the expression level of LXRa mRNA, which in turn activates the expression of liver SREBp-LC mRNA (Janowski et al. 1999). Therefore, LXRa and SREBp-LC can activate the transfer of key genes required for fat synthesis, such as fatty acid synthase and acetyl cocarboxylase (Demeure et al. 2009). Lu et al. (2007) stated that chronic heat stress negatively affects fat storage and meat quality in broiler chickens, and through the increase of lipoprotein lipase in the adipose tissue of animals, it increases the capacity of harvesting and storing intestinal and liver-derived triglycerides in fat tissue. Conclusion: In general, exposure to chronic heat stress further decreased yield and increased carcass fat and increased the relative expression of fatty acid synthase genes in the liver and lipoprotein lipase in the breast. [ABSTRACT FROM AUTHOR]

Introduction: During pregnancy, especially the period around birth, animals make many metabolic adjustments to support the transition from pregnancy to lactation. Since the last two months of pregnancy (late pregnancy) constitute 75% of fetal growth, therefore, enriching the sheep diet can have positive consequences on the health and general performance of the ewe and lamb. In such conditions, using of management and nutritional strategies will reduce the problems during the transition period and heat stress condition. Under stress condition, the mobilization of glycogen reserves and glucose production occur to produce energy to maintain stability in the body. Chromium is one of the scarce essential minerals that plays an important role in the metabolism of carbohydrates, lipids, proteins and nucleic acids. Chromium is part of the glucose tolerance factor that increases the affinity of insulin receptors to insulin hormone and increases the sensitivity of receptors to insulin. Material and Methods: This experiment was conducted to evaluate the effect of different forms of chromium in ewes during the transition period under the heat stress condition. Forty pregnant Afshari ewes from 42±5 days before the expected lambing were assigned to four treatments with 10 replications in a completely randomized design. Experimental treatments included: 1) basal diet without chromium supplementation (control), 2) basal diet containing three milligrams of inorganic chromium per kg of DM, 3) basal diet containing three milligrams of chromium in the form of chromium-methionine per kg of DM and 4) basal diet containing three milligrams of chromium in the form of chromium nanoparticles per kg of DM. Results and Discussion: The results showed that ewes receiving chromium had less weight changes at two, four and six weeks after lambing (P≥0.05). Also, supplementation of different forms of chromium increased the body condition score of ewes at the time and six weeks after lambing (P≥0.05). Ewes receiving chromium-methionine and chromium nanoparticles had better body condition than control and inorganic chromium treatments. There was no significant difference in glucose concentration between the treatments 60 and 90 minutes after intravenous glucose injection. After 60, 90, 120 and 180 minutes after the intravenous injection of glucose, the insulin concentration of the ewes receiving different forms of chromium decreased compared to the control treatment (P≥0.05). Conclusion: In general, the use of chromium, especially in the form of chromium-methionine and chromium nanoparticles, is recommended during the transition period of ewes under the influence of heat stress. [ABSTRACT FROM AUTHOR]

Oxidative stress plays a key role in sperm structure and function, semen quality and fertility. In poultry industries lipid peroxidation increases under chronic heat stress, particularly when the temperature exceeds 27 °C. In this situation, some practices are taken. One of important action is using pharmacological plant because of the lowest side effects. There is an increasing interest for applying natural antioxidants compare to synthetic because of the safety and low toxicity problems. The pharmacological plant generally used among foods. The use of natural antioxidant decreases sperm disorders and increases fertility. The rosemary has biological antioxidant mechanisms and belonging to thorny pharmacological plant, which is widely distributed in Europe and South-Eastern Asia. It has used in traditional medicine for its therapeutic properties. The Rosemarinus officinalis L. an evergreen perennial aromatic shrub belonging to the family Labiatae, commonly called rosemary. The rosemary is commonly used as a spice and flavoring agent in food processing. The rosemary contains some antioxidant phenolic that have been shown to provide a defense against oxidative stress from oxidizing agents and free radicals. The antioxidant capacity of rosemary is mainly related to the presence of components like carnosol, rosmanol, isorosmanol, epirosmanol, carnosic and rosmarinic acids. The antioxidant capacity of sperm is low, but enzymatic and non-enzymatic antioxidants in the seminal plasma protect sperm by scavenging the reactive oxygen species (ROS). [ABSTRACT FROM AUTHOR]

Introduction: Many industries have multiple factors harmful to health, leading to simultaneous exposure of these factors to each other. Noise is one of the most common physical parameters in the work environment. On the other hand, heat is also increasing due to various energy processes in industries. Therefore, this study was conducted with the aim of determining changes in physiological parameters and visual-auditory attention in acute exposure to heat and noise. Material and Methods: In this experimental study, 72 individuals (36 men and 36 women) aged between 23 and 33 years participated according to the inclusion criteria. In total, 12 different test modes were performed (3 temperature levels and 4 noise pressure levels). The test was conducted for each person in 4 steps during a specific day. The duration of exposure to each condition was half an hour, and a half-hour rest was given between each test condition. Saliva samples of each subject were collected before and immediately after exposure to noise and heat. Also, The Integrated Visual and Auditory (IVA) was recorded by the participants simultaneously. Results: The results of combined exposure to noise and heat on visual and auditory attention showed that only two modes of combined exposure, SPL95+WBGT34 and SPL95+WBGT29, caused a significant increase (P < 0.05) in mental workload and a significant decrease (P < 0.05) in visual and auditory attention. In addition, the results showed that independent exposure to noise at the levels of 85 and 95 dB and exposure to heat at higher temperature levels of 34 and 29 degrees Celsius cause a significant increase (P < 0.05) in salivary cortisol after exposure. The results of the effect of combined exposure to noise and heat on salivary cortisol showed that three experimental modes of combined exposure (SPL85+WBGT34, SPL95+WBGT29, and SPL95+WBGT34) caused a noticeable and significant (P

IntroductionIn the pursuit of a resilient and progressive agricultural system, the incorporation of diverse fertilizers is deemed essential. This practice not only enhances product quality but also aids in cost reduction. However, over-reliance on a specific type of input can inadvertently lead to unintended repercussions. The unrestricted utilization of chemical fertilizers, for instance, can precipitate adverse outcomes such as imbalanced pH levels, the accumulation of heavy elements, soil structure deterioration, and environmental contamination. Conversely, organic fertilizers, while environmentally friendly, often release nutrients at a slower rate, potentially disrupting optimal plant growth. To attain a balanced and sustainable agricultural approach, the combined application of organic and chemical fertilizers is advocated. Moreover, harnessing the biological potential inherent in soil ecosystems, including beneficial microbial communities encompassing bacteria and fungi, emerges as a promising avenue in cultivating sustainable agriculture. Acknowledging the adverse impact of late-season heat stress on wheat production in Khuzestan and recognizing the significance of reducing chemical fertilizer usage while augmenting organic and biological fertilizers to foster ecological health, this experiment undertakes the exploration of the effects of a synergistic approach. Specifically, it delves into the combined utilization of nitrogen and compost fertilizers, complemented by the incorporation of plant growth-promoting rhizobacteria. This endeavor aims to shed light on how this combined strategy operates within the context of terminal heat stress, assessing its influence on the physiological attributes and yield of the wheat cultivar Chamran 2.Materials and MethodsThis experiment was carried out as split-split plots based on a randomized complete block design with three replications in the crop year of 2021-2022 in the research farm of Agricultural Sciences and Natural Resources University of Khuzestan. The experimental factors include three planting dates: December 1st, December 20th, and December 10th in the main plots; Six levels of combined use of nitrogen fertilizer with compost fertilizer include control (without nitrogen and organic), 100% nitrogen, 75% nitrogen+ 25% compost, 50% nitrogen+ 50% compost, 25% nitrogen+ 75% compost and 100% compost in sub-plots and two levels of application and non-application of plant growth promoting rhizobacteria in sub-plots. Each sub-plot was 3 meters long and 2 meters wide (with an area of 6 square meters) and included 10 crop lines at a distance of 20 cm from each other. The distance between the main and secondary plots was considered to be half a meter and the distance between the blocks was two meters. After physiological maturity, the plants were harvested and the physiological traits and grain yield were measured.Results and DiscussionVariance analysis showed that the interaction effect of planting date, combined use of nitrogen with compost, and plant growth promoting rhizobacteria, on the traits of relative leaf water content, planting to flowering, and grain yield were significant at the 1% probability level. Also, the interaction effect of planting date and the combined use of nitrogen with compost on all traits except the length of the grain filling period and the length of sowing to physiological maturity was significant at the probability level of 1%. The mean comparison showed that the highest relative leaf water content, cell membrane thermostability, and canopy temperature depression were obtained from the treatment of 100% compost, and the highest traits of the length of sowing to flowering and length of sowing to physiological maturity were obtained in the use of 100% nitrogen. Also, the longest grain filling period, grain filling rate, and grain yield were obtained in the combined use of 50% nitrogen+ 50% compost and plant growth-promoting rhizobacteria, and the lowest value was obtained in the control of not using nitrogen and compost. In general, the delay in planting and the occurrence of terminal heat stress caused a decrease in grain yield, but on different planting dates, the combined use of 50% nitrogen+ 50% compost compared to the treatment of 100% nitrogen increased wheat grain yield.ConclusionAccording to the obtained results, in areas with terminal heat stress, the combined use of 50% nitrogen+ 50% compost and plant growth-promoting rhizobacteria can be considered to increase the growth and yield of wheat.

Background and purpose: Heat stress in most parts of the world has a negative effect on the yield of dairy cows and decreases milk production in high-yield dairy cows. Supplementation of feed of high-yielding cows with micronutrients (minerals and vitamins), especially in pre-natal period, can have some benefits in reducing the negative effects of heat stress and improving bovine yield in the next lactation period. This study was conducted to investigate the effect of some micronutrients on physiological and functional processes of dairy cows under heat stress. Materials and Methods: In this study, 24 lactating cows were used during transition. The cows were randomly divided into two groups of 12 and each group were assigned to an experimental treatment. Treatments included control group: only from conventional diet without adding micronutrients and the second group received micronutrients for 21 days before delivery. After delivery, each group was divided again into two groups of 6, so that each group was fed either micronutrient free or micronutrient enriched diet for 21 days after delivery. Supplementation containing micronutrients of the progenitor period included micronutrients of selenium, copper, zinc, chromium, vitamin A, vitamin E, magnesium, ascorbic acid and niacin and the micronutrient supplementation of the new period contained sodium and potassium in addition to the above micronutrients. The average temperature-humidity index during the experiment period was 74 and the cows were under heat stress. The conditions of storage, nutrition management and environment were the same for all animals during the whole experiment. Changes in weight, feed intake and rectal temperature were determined four hours after feeding on two consecutive days. The weight of the born calf, the weight of the placenta, and the amount of colostrum produced during the first three milks were recorded. Results: The amount of dry matter consumption during the reproductive waiting period was higher in the micronutrient group compared to the control group, which was significantly different in the last week of pregnancy (P<0.05). Although weight gain during the anticipation period was not affected by treatment, more weight gain was observed in the micronutrient group. The number of days of pregnancy in cows receiving micronutrients was longer than the control group. Colostrum production was also higher in this group. The weaning weight of the calves was not affected by the treatments. The feed consumed during lactation period was affected in the first week of lactation, and the micronutrient receiving treatment had the highest feed intake in the third week in the transition period, in parallel with milk production of this group was higher than other groups and its difference with other treatments was significant (P<0.05). Milk composition was not affected by treatments ( P>0.05 Conclusion: This experiment showed that heat stress can have a negative effect on dairy cows during the transition period and the use of micronutrients during this period can have beneficial effects on the repair of heat induced stress in dairy cows. [ABSTRACT FROM AUTHOR]

Introduction Among the most common problems and stress in the conditions of Khuzestan province, heat stress at the end of the season and the deficiency of nutrients, which occurs in different periods of rapeseed growth, depending on their severity, causes physiological and metabolic disorders and ultimately reduces the yield of rapeseed plants with different intensity depending on the type of plant genotype, they affect Materials and Methods With the aim of evaluating the growth and yield response of rapeseed cultivars (Brassica napus) to boron element levels in late season heat stress conditions caused by late sowings dates, this study was carried out in a split-split plot arrangement in the form of a randomized complete block design with three replications. The expeiment was carried out in the crop year of 2021-2022 in the research farm of Agricultural Sciences and Natural Resources University of Khuzestan. Sowings dates (November 21, December 11, and December 31) in the main plots, four levels of boron (zero, 4, 8, and 12 kg/ha) in the subplots and rapeseed cultivars (RGS, Zafar, and Saffar) in the sub-sub-plots were investigated. Results and Discussion The results of the research showed that sowing date and end of season heat stress in Khuzestan conditions had a significant effect on most of the studied physiological traits, seed yield and biological yield. In addition, the effect of boron on traits such as leaf area index, leaf area ratio, and relative moisture content of leaf water, leakage of electrolytes, grain yield and biological performance was significant. The triple interaction effect of planting date, boron and variety was also significant on traits such as relative moisture content of leaf water, leakage of electrolytes, grain yield, and biological performance. So that with the delay in planting and the consequent increase in temperature and heat stress at the end of the season in the period of growth of the rapeseed plant, it causes a decrease in traits such as leaf area index, relative moisture content of leaf water, leaf area ratio, leaf specific area, seed yield and biological yield. And conversely, due to the heat stress at the end of the season, the leakage of electrolytes and the canopy temperature increased significantly. In general, the highest seed yield was obtained in Safar variety on the sowing date of December 11 and the boron level was 4 kg/ha with an average of 4590 kg/ha. Also, the highest average leaf area index was observed on the first sowing date and Safar variety with an average of 5.43 and the lowest value was observed on the third sowing date and Safar variety with an average of 2.11. It was also observed that the application of boron caused a significant decrease in the leaf area index in all three studied cultivars. This issue can indicate the lower need of boron consumption of the studied cultivars in this experiment. Conclusion In general, the heat stress at the end of the season, which occurs in different periods of rapeseed growth, especially the seed filling period, depending on its intensity, causes physiological disorders in the plant and finally affects the grain yield with different intensity and depending on the genotype of the plant. The analyzed rapeseed genotypes also showed tolerance to different levels of boron element in the heat stress conditions of the end of the season and showed different reactions with different amounts of boron consumption per hectare. [ABSTRACT FROM AUTHOR]

In the poultry industry, the heat stress caused by high environmental temperature has a negative influence on broiler chicken performance and has become a major challenge. Transcriptome profile analysis of the data and identification of patterns of differential gene expression in related tissues can be involved in the discovery of molecular mechanisms resistant to heat stress. The main purpose of this study was to use transcriptome profiles of three tissues brain, liver, and leg muscle of two groups of the control and heat stress broiler chickens to identify candidate genes associated with heat stress. By the analysis of microarray data to express the gene differences, 657 significant genes (P<0.05) were extracted, which a total of 94 genes showed significant expression differences (FDR < 0.05, Fold change > ± 2). Then, by studying the ontology of the relevant genes resulting from data analysis and literature mining as well as the reconstructed protein-protein interaction network, hub genes including NSDHL, DHCR24, LSS, FDPS, PCK1, ACTA1, HSP90AA1, HSPA2, HSPB1, HSF1, CRYAB, APOB, and IL6 were identified. Annotation results of these genes indicated that they have a role in the main process of metabolic and signaling pathways related to the ion transport system, steroid, antibodies, cholesterol biosynthesis, lipid metabolism, immune system function, and various signaling pathways such as MAP kinase, RET, and ERK. Overall, the present study can provide new insights into evidence of the pathways activated by these genes to identify effective genes and a better understanding of biological processes related to heat stress. [ABSTRACT FROM AUTHOR]

Background and Objectives: Heat stress (HS) potentially has several physiological complications that lead to great economic losses in the sheep and goat breeding industry, including reproductive disorders, immune system weakness, inflammation, electrolyte imbalance, and reduced feed intake. Glutamine is the most abundant amino acid in the body and this amino acid has different roles such as building proteins, increasing nitrogen balance, stimulating the immune system, anabolic and anti-catabolic effects on muscles, anti-inflammatory and antioxidant. This experiment was conducted to evaluate the effects of glutamine supplementation and protein level (equal to and 10% higher than the National Research Council requirement) on blood parameters, inflammatory and immune indices of fattening lambs during heat stress. Materials and Methods: In this study, 16 Afshari male lambs with an average weight of 31.5 ± 0.22 kg and an average age of 3 to 4 months were used. The experimental lambs were tested in 4 treatments and 4 repetitions in a completely randomized design and a 2x2 factorial method for 45 days. Experimental treatments include 1- basic diet (metabolizable protein equal to requirements), 2- basic diet with glutamine (0.2 grams per kilogram of body weight), 3- diet with 10% more metabolizable protein than requirements, and 4- The diet had 10% higher metabolizable protein with glutamine (0.2 grams per kilogram of body weight). Blood sampling was done from the jugular vein two hours after the morning meal on the 15th, 30th, and 45th days of fattening with the help of Venoject tubes containing anticoagulants. Blood parameters including albumin (Alb) and total protein (TP) of plasma, alkaline phosphatase (ALP), and malondialdehyde (MDA) were measured with relevant kits and with an automatic analyzer. The concentration of cytokines including interleukin 2 (IL-2), interleukin 6 (IL6), and interleukin 10 (IL-10) as well as Immunoglobulin G (IgG) was measured using ELISA kits. Results: The effects of the treatments on blood Alb on the 15th day of fattening did not show any significant difference. While on days 30 and 45 of fattening, the effects of treatments on blood Alb were significant (P=0.0217 and P=0.0087, respectively). Glutamine increased total plasma protein concentration on days 30 and 45 (P=0.0071 and P=0.0019, respectively). Also, increasing the protein level in the diet of fattening lambs on days 30 and 45 increased the TP of plasma (P=0.0139 and P=0.0386, respectively). On the 45th day of fattening, the addition of glutamine increased the blood ALP enzyme (P=0.0123). Also, taking glutamine supplements on the 30th and 45th days of fattening decreased MDA (P=0.0012 and P=0.0029, respectively). There was no significant difference in the number of red blood cells, hemoglobin level, hematocrit, mean concentration of hemoglobin in cells, and mean cell volume between treatments on the 15th and 30th days of fattening. While on day 45, glutamine decreased the number of red blood cells and hematocrit percentage (P=0.0036 and P=0.0081, respectively). The number of white blood cells increased on the 30th and 45th days of fattening with the addition of glutamine (P=0.0004 and P=0.0012, respectively). The effect of treatments on blood IgG, IL-2, and IL-10 on the 15th day of fattening was not significant, while the treatments on the 30th and 45th day of fattening increased the values of IgG (P=0.0287 and P<0.0001, respectively). In addition, IL-2 increased on days 30 and 45 under the influence of treatments (P<0.0001 and P<0.0001, respectively). On the 30th and 45th days of fattening, the addition of glutamine increased the levels of IL-10 (P=0.0194 and P=0.0007, respectively). The concentration of IL-6 on the 45th day of fattening decreased with the addition of glutamine and the addition of metabolizable protein levels (P=0.0004 and P=0.0233, respectively). Conclusion: According to the results obtained from this research, the albumin and protein levels of the whole blood, the number of white blood cells, the amount of immunoglobulin G were the highest in the groups fed with treatments 2 and 4 and the lowest in the control group. In this study, glutamine significantly reduced the number of red blood cells and hematocrit percentage. Treatments 2 and 4 significantly increased antiinflammatory cytokines (interleukin 2 and 10) and decreased proinflammatory cytokine interleukin 6. In general, according to the results of this study, the simultaneous use of glutamine supplement and a higher level of metabolizable protein (treatment 4) is suggested. [ABSTRACT FROM AUTHOR]

Introduction: Heat and its effects are considered one of the serious threats and damages to the production of agricultural and horticultural crops in many regions of the world. Therefore, it has led to pervasive changes in terms of morphological, physiological, anatomical, and molecular, which causes a sharp decrease in the economic performance of agricultural products. Nowadays, in order to reduce these inhibitory effects, in addition to classical and conventional breeding methods, modern and molecular methods can be used to identify heat-tolerant genes and use them in breeding programs to improve plant tolerance to environmental stresses. Materials and methods: The selection for heat tolerance among four local cultivars Hovyzeh, Hamar, Red-Anbori, Champa and three promising heat tolerant lines V1, V2 and V3 obtained from the international breeding programs of Khuzestan Agricultural Research and Training Center and Natural Resources were evaluated by osHATS and HSP70 genes qPCR on two experimental cultivation dates: May 20 (unfavorable) and June 20 (favorable) 2022 in Ahvaz. Results: The results obtained from the analysis of gene expression by qPCR on the date of the first cultivation confirmed the presence of the osHTAS gene in rice varieties and lines so that the local variety Champa, Hovyzeh, and line V2 has a high relative gene expression compared to other varieties and lines studied and they were significantly different from each other. The analysis of the osHTAS gene expression on the second planting date (June) in Ahvaz also shows the presence of the high-temperature tolerance gene in Hovyzeh, Hamar and V2 lines; therefore, the mentioned varieties could be used as parental lines for transfer heat tolerance gene to be used in multi-breeding programs and terms of the relative expression level of the gene, they showed a statistically significant difference with each other. The results of the relative gene expression of the HSP70 gene in the cultivation date of May showed that the local cultivars Champa, Red-Anbori and Hovyzeh had a remarkable superiority over the others. Examining the HSP70 gene expression pattern of rice cultivars and lines on the second planting date also revealed that the local cultivars Red-Anbori, Champa, Hovyzeh, and Hamar showed superiority. The tolerance of local cultivars to heat stress is due to their rapid growth and the creation of a large green cover in the early stages of growth, and their great adaptation to the region's environmental conditions. Conclusion: Local cultivars can withstand heat stress well with rapid growth and creating much vegetation due to their high adaptability to environmental conditions and the presence of heat stress tolerance genes. They could be used as parental lines in breeding programs.

Introduction: Heat stress can compromise sheep's productive performance and growing lambs are considered to be one of the most susceptible groups to heat stress. Exposure to heat stress increases inflammatory cytokines secretion and impairs insulin signaling in muscle which may underlie poor growth responses. Therefore, enhancing insulin sensitivity through the addition of insulin-sensitizing dietary additives may improve animal performance during heat stress. Phytogenics, compounds with antioxidant, antimicrobial, and metabolic enhancing effects, have been used in animal nutrition to enhance performance and prevent diseases in stressrelated conditions. It has been reported that supplementing a phytogenic-rich herbal mixture containing clove, rosemary, cinnamon, and turmeric improved the antioxidant status and enhanced insulin sensitivity of transition dairy cows. It has been indicated that the duodenal infusion of quercetin increased insulin secretion and insulin sensitivity. Possible mechanisms responsible for the insulin-sensitizing activity of herbal plants include increasing insulin receptors or enhancing receptor sensitivity to insulin, increasing PPARy activity, increasing glycogen synthase activity, modulating inflammatory cytokine expression, stimulating fatty acid oxidation as well as increasing antioxidant status. The objective of this study was to investigate the effects of a phytogenic-rich herbal mixture (PRHM) supplementation on gene expression of insulin-related genes in the muscle of feedlot lambs experiencing severe heat stress conditions. Materials and methods: Eighteen 11-12-month-old growing male Afshari×Chaal lambs (41.2 ± 3.04 kg) were housed in individual stalls (1.2 × 1 m, with individual feed troughs) on wooden slatted flooring, located within an indoor animal facility with a natural and artificial lighting system for 16 h/d. Lambs were randomly allocated to one of three experimental diets for a 48-day feeding period. The treatments included control diet without PRHM (0%PRHM), diet supplemented with 1% PRHM (1%PRHM), and diet supplemented with 2% PRHM (2%PRHM). The PRHM was added to the basal diet and mixed thoroughly. Diets formulated to meet nutritional requirements for maintenance and growth and offered twice daily at 0700 and 1700 h. The lambs had free access to feed and water during the experiment. The main ingredients of the basal diet were alfalfa hay, ground corn, wheat bran, beet pulp, soybean meal, and soy oil. The herbal mixture consisted of 50% rosemary leaves (Rosemarinus offıcinalis), 20% cinnamon barks (Cinnamomum zeylanicum), 20% turmeric roots (Curcuma longa), and 10% clove buds (Eugenia caryophyllata Thunb.). The total phenolic content of the PRHM was 89.6 g tannic acid equivalent per kg. The daily climate data, such as daily mean temperature and relative humidity, were recorded using a digital thermo-hygrometer (Testo 608-H1, Germany). At the end of the study, all lambs were transported to a local abattoir where they were slaughtered after 12-h feed withdrawal according to Halal method. Post-slaughter, longissimus lumborum muscle samples between the 12th and the 13th rib of the right side of carcass were collected as quickly as possible (i.e., within 3-5 min). For expression analysis of Insulin receptor (INSR), Insulin receptor substrate 1 (IRS1), glucose transporter 1 (GLUT1), glucose transporter 4 (GLUT4), Peroxisome Proliferator-Activated Receptor Gamma (PPARγ) genes, total RNA was isolated from the sheep muscle tissue using the SinaPure RNA according to the manufacturer's instructions. The quantity and integrity of isolated RNA were determined for each sample by using both NanoDrop (260/280 ratio) and 1% agarose gel electrophoresis. cDNA was synthesized with RevertAid First Strand cDNA Synthesis Kit according to the manufacturer's instructions. Forward and reverse primers were designed for five genes and GAPDH as reference gene by Oligo 7. The real-time PCR was done in 25 μL containing 1x BIORON GreenHot Master Mix (BIORON, Germany), 1 μL cDNA, 0.3 μM of each forward and reverse primers and nuclease-free water to reach final volume. Real-time PCR was performed on Bio-Rad CFX96 as follows; Initial denaturation 2 min at 94 °C, followed by 39 cycles of denaturation 20 sec at 94 °C, annealing 25 sec at annealing temperature, extension 20 sec at 72 °C following by melting curve analysis from 65 °C to 95 °C with 0.5 °C increase per each step. Relative gene expression was determined based on Livak method (2-ΔΔCT). All data were analyzed using the MIXED procedure of SAS. Model included the effect of the treatment as the fixed effect and lambs within treatments as a random effect. The significance level was declared at P<0.05. Results and discussion: The results showed that the gene expressions of INSR (P<0.01) and GLUT4 (P<0.01) in muscle tissue were linearly upregulated in lambs supplemented with increasing levels of herbal mixture. A quadratic effect of herbal mixture supplementation was found on gene expression of IRS1 such that lambs fed a 2% mixture had the highest gene expression. Moreover, both supplementation levels of 1 and 2% mixture equally increased GLUT1 gene expression (P<0.01) compared to control lambs. In contrast to the other genes, PPARγ gene expression was quadratically (P<0.01) downregulated by mixture supplementation such that the lowest gene expression was observed in lambs receiving a 2% mixture. Although there is some evidence suggesting that PRHM supplementation has modulatory effects on insulin resistance in transition dairy cows, to our knowledge, there is currently no published data investigating the effects of PRHM supplementation on mRNA expression of genes related to insulin and glucose metabolism in lambs' skeletal muscle. Our results may suggest that PRHM supplementation enhanced insulin sensitivity and glucose uptake in the skeletal muscle of heat-stressed lambs. In agreement with our results, it has been found that cinnamaldehyde promotes gene expression of IRS-1 and GLUT4 genes in muscle cells, which the latter gene is affected by activating the peroxisome proliferator-activated receptor gamma coactivator 1-alpha. In addition, greater GLUT1 gene expression might be indicative of improved insulinindependent glucose uptake, besides enhanced insulin-dependent glucose transporter, GLUT4 gene. Conclusions: The results showed that the mixture of medicinal plants including cinnamon, turmeric, rosemary, and clove affected the expression of genes related to insulin metabolism and increased the efficiency of glucose utilization. [ABSTRACT FROM AUTHOR]

Introduction: Heat and its effects are considered one of the serious threats and damages to the production of agricultural and horticultural crops in many regions of the world. Therefore, it has led to pervasive changes in terms of morphological, physiological, anatomical, and molecular, which causes a sharp decrease in the economic performance of agricultural products. Nowadays, in order to reduce these inhibitory effects, in addition to classical and conventional breeding methods, modern and molecular methods can be used to identify heat-tolerant genes and use them in breeding programs to improve plant tolerance to environmental stresses. Materials and methods: The selection for heat tolerance among four local cultivars Hovyzeh, Hamar, Red-Anbori, Champa and three promising heat tolerant lines V1, V2 and V3 obtained from the international breeding programs of Khuzestan Agricultural Research and Training Center and Natural Resources were evaluated by osHATS and HSP70 genes qPCR on two experimental cultivation dates: May 20 (unfavorable) and June 20 (favorable) 2022 in Ahvaz. Results: The results obtained from the analysis of gene expression by qPCR on the date of the first cultivation confirmed the presence of the osHTAS gene in rice varieties and lines so that the local variety Champa, Hovyzeh, and line V2 has a high relative gene expression compared to other varieties and lines studied and they were significantly different from each other. The analysis of the osHTAS gene expression on the second planting date (June) in Ahvaz also shows the presence of the high-temperature tolerance gene in Hovyzeh, Hamar and V2 lines; therefore, the mentioned varieties could be used as parental lines for transfer heat tolerance gene to be used in multi-breeding programs and terms of the relative expression level of the gene, they showed a statistically significant difference with each other. The results of the relative gene expression of the HSP70 gene in the cultivation date of May showed that the local cultivars Champa, Red-Anbori and Hovyzeh had a remarkable superiority over the others. Examining the HSP70 gene expression pattern of rice cultivars and lines on the second planting date also revealed that the local cultivars Red-Anbori, Champa, Hovyzeh, and Hamar showed superiority. The tolerance of local cultivars to heat stress is due to their rapid growth and the creation of a large green cover in the early stages of growth, and their great adaptation to the region's environmental conditions. Conclusion: Local cultivars can withstand heat stress well with rapid growth and creating much vegetation due to their high adaptability to environmental conditions and the presence of heat stress tolerance genes. They could be used as parental lines in breeding programs. [ABSTRACT FROM AUTHOR]

In recent years, the application of spore-forming bacteria in probiotic food supplements and medicine have become more interesting due to their stability in stressful condition of production line and gut environment. In the current study, the resistance of Bacillus coagulans and Bacillus subtilis in response to heat stress and simulated gastrointestinal tract was investigated. Moreover, the aggregation and hydrophobicity of cell surface of these strains were evaluated. The results showed a survival rate of more than 80% for both species after enduring heat stress and undergoing simulated gastrointestinal conditions. In addition, Bacillus coagulans showed a higher autoaggregation and coaggregation ability compared to Bacillus subtilis. In addition, both probiotic species presented a high tendency toward adhering to the hydrocarbon solvents like chloroform and ethyl acetate. This study was a continuation of previous studies conducted with the aim of developing and optimizing functional edible coating for the production of probiotic rock candy (Nabat) using spore-forming probiotic bacillus, to ensure the survival and effectiveness of the strains.

Background and objectives: Rising temperatures are a severe warning to humans, and heat stress is one of the principal environmental stresses that reduce the yield of crops, including wheat, worldwide. The increase in carbon dioxide in the atmosphere has caused global warming, affecting agriculture in the future. More than 50 countries experience heat stress during the wheat growing season. Therefore, the development of heat-tolerant cultivars is one of the main goals of wheat breeding programs. This study aimed to evaluate the drought tolerance indices and determine the relationships among them and their application in wheat screening programs. Materials and Methods: This experiment was performed using alpha-lattice design with two replications in normal and delayed cultivation conditions using 132 wheat genotypes (included 62 Iranian and foreign cultivars and 70 advanced lines). The seeds were obtained from the National Rainfed Agricultural Research Institute and the Seedling and Seed Breeding Institute. Two local control cultivars named Gonbad (Abi cultivar) and Kuhdasht (rainfed cultivar) were selected among the selected genotypes. Based on the yield under non-stress (YP) and stress (YS) conditions, tolerance indices such as stress tolerance index (STI), tolerance index (TOL), Geometric mean production (GMP), mean production index (MP), Harmonic Index (HM), Yield Index (YI), Relative Drought Index (RDI) and yield Stability Index (YSI) were calculated. Results: The results showed that tolerance indices such as STI, GMP, HM, and MP had a positive and significant correlation with yield under non-stress and stress conditions, and the genotypes with large numerical values for these indices had high yield under stress and non-stress conditions (Fernandez’ A group), which were included genotypes 51, 12, 24, 85, 6, 120, 47, 94 (Bahar), 72, 114, 91, 131, 16, and 127. Tolerance indices were divided into two components that explained 90.79% of the total variance, using principal component analysis. The first component, which explained 60.64% of the total variance, had a correlation of 0.75 and 0.86 with performance under stress and non-stress conditions, respectively. The second component, which explained 30.14% of the total variance, showed a correlation of 0.66 and -0.5% with performance under stress and non-stress conditions, respectively. Based on the two-dimensional plot resulting from principal component analysis, considerable genetic diversity was observed among the studied genotypes. Conclusion: According to the results, genotypes that perform well under non-stress conditions will not necessarily perform well under stress conditions. Therefore, to select high-yield genotypes under stress conditions, the cultivar selection had to be made in the same stressful environment. In conclusion, it can be said that the identified genotypes using HM, GMP, and MP indices are recommended for cultivation in areas with no stress, but heat stress is likely to occur in some years. In addition, identified genotypes using YSI and RDI indices are recommended for cultivation in areas with severe heat stress at the end of the season. Accordingly, stress-resistant genotypes in F or A group C can be used as germplasm sources with heat-tolerant genes in breeding programs. Also, to locate heat stress tolerance genes, it is possible to use the intersection of genotypes located in group B of Fernandez with genotypes located in group A or C of Fernandez. [ABSTRACT FROM AUTHOR]

Heat stress is the most important climate feature of Khuzestan province and the most influential atmospheric phenomenon on manpower in the study area. In this study, in order to investigate the temporal and spatial heat stress affecting the manpower of military units based in Khuzestan province, First, a special exploratory study was conducted on the subject and method of research, and then the physiological equivalent temperature index was compared with the standard effective temperature index and the physiological equivalent temperature index was found to be more appropriate for this research. Data from 12 synoptic stations in the study area with a statistical period of 30 years (1990-2020) have been used to extract the index. Data on climatic parameters including wind speed, temperature, relative humidity, water vapor pressure and cloud cover were received daily from the Meteorological Organization and GIS software was used to draw the map. The research findings show that the trend of index changes in the last 30 years has been increasing and is projected to reach 18,088 in 2030. The stations of Abadan, Omidieh, Hindijan and Bostan in the west and south of the region are the most days with heat stress and the most unfavorable place for manpower in military units in the region. In terms of time, July and August are the worst times for the use of manpower in the region, respectively, and the months of November and March have the best conditions for the use of manpower in military units based in Khuzestan province.

In order to evaluate the ability of wheat cultivars to accumulate reserves in the stem and remobilization of these reserves to seeds under heat stress resulting from delayed sowing and to investigate the effect of phosphate-solubilizing bacteria on this ability, this study was carried out as split factorial based on a complete randomized block design with three replications in Haftkol, Khuzestan, Iran, in the growing season of 2016-2017. The main factor consisted of sowing date in two levels (22 November as conventional and 2 January as delayed seeding dates) and a factorial of the two subfactors consisting of five bread wheat cultivars (Chamran2, Mehregan, Sirvan, Shush and Barat) and two levels of application of phosphate solubilizing bacteria, Pseudomonas putida (P13) and Pantoea agglomerans (P5), (inoculation and without inoculation). The results showed that the reduction of stem specific weight (28.5%), stem length (18.7%) and effective grain filling duration (38.3%) were the most important reasons for reducing dry matter remobilization to stem and the efficiency of this remobilization in delayed sowing. At both sowing dates under bacterial seed inoculation conditions, the dry matter remobilization efficiency was 8.5% lower than the non-inoculated conditions. In the conventional sowing date, the relationship between spike weight and dry matter remobilization was positive and significant, but at delayed sowing date, spike weight and grain yield were not significantly related to dry matter remobilization and efficiency. In general, stem specific weight was recognized as the most important factor affecting the accumulation of reserves in the stem and Mehregan cultivar, with the ability to utilize stem reserves, was introduced as a suitable cultivar for delayed cultivation in the region.

Introduction: Prevention of heat-related diseases requires the participation of the workers. For this reason, the aim of this study was the development and validation of the tools for evaluating awareness and practice related to heat stress among the workers of warm workplaces. Material and Methods: The various items and factors related to the awareness and practice of the workers were identified by the literature review. Then, several questions for evaluating these items were designed. In the next step, the reliability and validity of the questionnaires were appraised using calculating the content validity ratio (CVR) and content validity index (CVI), and Cronbach’s alpha coefficient, respectively. After that, these questionnaires were completed by 2338 employees of six industries in various regions of Iran. Finally, collected data were analyzed using SPSS software. Results: In total, 77 questions, including 53 questions on awareness and 24 questions on practice in six groups of water and beverages, food, snacks and additives, heat exchange, thermal strain risk factors, clothing and heat protection equipment, and heat-related disorders and body reactions, were designed. The values of content validity index (CVI) of remained questions in the questionnaires of awareness and practice were equal to 0.954 and 0.824, respectively. The values of Cronbach’s alpha coefficients of these questionnaires were calculated by 0.755 and 0.716, respectively. The values of the chi-square divided by degrees of freedom (CMIN/DF) and root mean square error of approximation (RMSEA) in the construction of the awareness questionnaire were computed as 4.58 and 0.079, respectively. These values in the construction of the practice questionnaire were calculated by 2.33 and 0.084, respectively. Conclusion: The results showed that the designed questionnaires had appropriate reliability and validity and could be used to evaluate the awareness and practice in warm workplaces.

Background: Heat is one of the most important physical harmful factors in many work environments. Due to the nature of work, bakery activity is considered as one of the high-risk occupations in terms of heat stress. Therefore, the aim of this study was evaluated of heat exposure in bakery workers using WBGT, HSI and UTCI indices. Methods: This study is a descriptive-analytical cross-sectional study that was conducted in bakeries in Bojnurd. In this study, heat stress was evaluated based on WBGT, HSI and UTCI indices. WBGT meters, thermometers and anemometers were used to measure the required parameters. Statistical analysis was performed by SPSS21 software. Results: The mean of WBGT, UTCI and HSI indices were 34.81 2.63, 37.02 3.54 and 64.65 24.23, respectively. The values of UTCI and WBGT indices except air velocity were significantly associated with all environmental parameters. There was a positive correlation between all physiological parameters and UTCI and WBGT indices. HSI index was significantly associated with oral temperature and mean skin temperature. There was a strong positive correlation between WBGT and UTCI and a weak positive correlation between HSI and WBGT and UTCI. Conclusion: There was a correlation between UTCI and WBGT as well as environmental and physiological parameters and a strong correlation was observed between UTCI and WBGT. It seems that UTCI is also suitable for assessing occupational heat stress in indoor environments such as bakeries.

Background Heat is one of the most important physical harmful factors in many work environments. Due to the nature of work, bakery activity is considered as one of the high-risk occupations in terms of heat stress. Therefore, the aim of this study was evaluated of heat exposure in bakery workers using WBGT, HSI and UTCI indices. Methods This study is a descriptive-analytical cross-sectional study that was conducted in bakeries in Bojnurd. In this study, heat stress was evaluated based on WBGT, HSI and UTCI indices. WBGT meters, thermometers and anemometers were used to measure the required parameters. Statistical analysis was performed by SPSS21 software. Results The mean of WBGT, UTCI and HSI indices were 34.81 2.63, 37.02 3.54 and 64.65 24.23, respectively. The values of UTCI and WBGT indices except air velocity were significantly associated with all environmental parameters. There was a positive correlation between all physiological parameters and UTCI and WBGT indices. HSI index was significantly associated with oral temperature and mean skin temperature. There was a strong positive correlation between WBGT and UTCI and a weak positive correlation between HSI and WBGT and UTCI. Conclusion There was a correlation between UTCI and WBGT as well as environmental and physiological parameters and a strong correlation was observed between UTCI and WBGT. It seems that UTCI is also suitable for assessing occupational heat stress in indoor environments such as bakeries.

Introduction: Heat stress is a critical problem in hot industries, especially in incredibly hot climates. It can greatly impair the work process and put the health of workers at risk. This study aims to investigate the applicability of the WBGT index in determining the allowable working time in very hot weather conditions in one of the steel industries in Ahvaz. Material and Methods: This study was conducted in different sectors of a steel industry in Ahwaz. The physiological parameters of sixty workers working in different parts of the industry were evaluated. Environmental variables and the Wet-Bulb globe temperature (WBGT) Index were also simultaneously measured during work shifts. The acceptable work time was calculated based on the reserve heart rate (RHR) and the WBGT index. Results: The heat stress index among all occupational groups, based on the WBGT index, was incredibly high and surpassed the recommended level (P

Introduction: One way to reduce the level of heat strain is to use personal evaporative cooling coats. such as the wrist, ankle, head and neck. The purpose of this study is to design, construct, and determine the cooling power of local cooling coatings and evaluate their efficiency in improving perceptual indicators in the laboratory. Materials and Methods: Initially, the design and construction of local cooling coatings were performed using anthropometry. Then the cooling power of the mentioned coatings was calculated. Finally, the efficiency of the coatings designed to improve perceptual indicators on 16 students (8 men and 8 women) was tested in a climate chamber with a temperature of 35 ± 0.23°C and a temperature of 30 ± 5%. Results: The average cooling power of cooling coats at 30% relative humidity at 30°C, 35°C and 40°C was 67, 77 and 89 watts, respectively. At the mentioned temperature and in 60% relative humidity, the cooling power was 34, 40 and 55 watts. As the relative humidity increased, the cooling power of the coats decreased. Also, the mean of thermal sensation and heat comfort during activity with a cooling cover and without a cooling cover in sitting and walking treadmill positions were significant (P-value≤0.05). Conclusion: Local evaporative cooling coat on the head, neck, wrists and ankles can be reasonably effective in repelling excess heat entering the body and improving perceptual indicators. The best performance of these coats is in hot and dry environments. [ABSTRACT FROM AUTHOR]

injuries, losses, and reduced productivity. The aim of this study was to investigate the relationship between heat stress and strain indices with human productivity in workers of a steam power plant. Methods: This descriptive cross-sectional study was performed on 104 workers of a steam power plant in summer season. Two indices of Wet Bulb Globe Temperature (WBGT) and Heat Strain Score Index (HSSI) were used to measure heat stress and strain, respectively. Human productivity was also measured using Hersey and Goldsmit 26-item scale. Data were analyzed using analysis of variance (ANOVA) test and Pearson correlation coefficient. Findings: According to ANOVA results, there was no significant difference in WBGT in three heights of head, waist, and ankle. The highest value of WBGT index was related to the 4th floor boiler unit (27.3 ± 5.6) and the lowest value was related to the administrative unit (16.9 ± 3.5). The maximum and minimum values of HSSI were obtained for the 3th floor boiler unit (27.2 ± 0.4) and workshop facilities (12.0 ± 3.0), respectively. The highest and lowest values of human productivity was related to the welding (97.0 ± 25.9) and boiler (28.5 ± 2.8) units, respectively. The results of ANOVA analysis showed that the values of WBGT, HSSI indices, and productivity subscales in different units were significantly different (P < 0.05). Pearson correlation coefficient analysis showed that there was a significant inverse relationship between productivity and its subscales with the amount of heat stress and strain (P < 0.05). Conclusion: There is a negative relationship between productivity, heat stress, and strain. Therefore, to protect workers' health and productivity, precautionary measures should be taken, including an appropriate rest-work ratio, short working hours, fluid replacement, and engineering controls such as the use of efficient cooling methods such as air conditioning, fan, or cooling clothing.

Introduction1 One of the most important environmental factors affecting the dairy industry is the temperature changes that showed a negative impact on the industry over the past few years. Increasing temperatures have declined the production and reproductive performance of herds in the tropics. Huge losses are caused annually due to heat stress. Heat stress in dairy cows is caused by a combination of environmental factors (temperature, relative humidity, solar radiation and air movement). Continual genetic selection for greater performance results to increased sensitivity to heat stress. It was one of the reasons why lactation curve during summer has decreasing trend compared to spring in which lactation curve maintained within high levels. Dairy cows at the beginning of lactation have small chances to fight off a thermal stress, and thus it has the strongest effect on the production of milk in the first 60 days of lactation. A negative balance of energy in dairy cows at the beginning of lactation is even more increased by creating and emitting of higher quantity of thermal energy in the period when animals consume less food. For this reason, a high-yielding dairy cows are more sensitive to heat stress than cows having a lower genetic potential for milk production. Impacts of heat stress on reproductive efficiency have been well documented and reviewed. Heat stress has been shown to alter the duration of estrus, colostrum quality, conception rate, uterine function, endocrine status, follicular growth and development, luteolytic mechanisms, early embryonic development and fetal growth. Therefore, the purpose of this study was to investigate the effect of heat stress on yield of dairy cattle in different months of production and also to estimate genetic parameters of production and reproductive traits under heat stress. Material and Methods In this study, 169655 records of 60322 dairy cows in different parity in Isfahan province of Iran were used. The studied traits included productive and reproductive traits. Milk test day and fat percent as productive traits and open days and days to first service were considered as reproductive traits. Climatic records of herds were collected from 7 stations less than 70 km away from herds and temperature-humidity index (THI) was calculated for each month in each herd. Dairy milk production records ranged from 5 kg to 60 kg for milk and milk fat percentage from 1 to 7%. Genetic and phenotypic trends were considered by regression of the estimated breeding values on year of the birth. The model used included the effect of herd-year of calving, calving month, parity and temperature-humidity index. An animal model was used to estimate genetic parameters of reproductive traits and random regression was used for production traits. SAS software was used to investigate the significance level of independent factors and DMU software was used to estimate genetic parameters. Results and Discussion The results showed that the threshold of temperature-humidity index is 72 and more than it has adverse effects on performance. Average days open and difference to first service in different Parity 112 and 60 days respectively and was estimated the average heritability of days open and difference to first service 0.02 and 0.06, respectively. With increase in temperature-humidity index, mean of production traits decreased and this decrease for milk and fat yield traits occurred at temperature-humidity threshold of 72 and 65, respectively. The average of heritability was calculated as 0.32 for milk yield and 0.24 for milk fat percentage. The results indicated that with increasing temperature humidity index in 72 the genetic variance for both traits was increased. In on other words, the cows after heat stress (THI=72). Genetic differences were significantly increased. The results of this study indicate that the additive genetic variances were higher in early lactation (5 to 100 days of lactation), for both milk yield and fat percentage. Conclusion Genetic variance increased with increasing temperature-humidity index (THI = 72) for the two traits of milk and fat production. Also breeding value of open day correction and difference to first calving under heat stress decreased. In other words, there is a significant genetic difference between animals exposed to heat stress after temperature-humidity index 72. Therefore, it may be possible to genetically identify animals more resistant to heat stress as parents of the next generation. [ABSTRACT FROM AUTHOR]

Introduction 1 This experiment was performed to evaluate the effects of peppermint extract, vitamins C, vitamin E, probiotics and antibiotics on performance, biochemical parameters and immune system of broilers under heat stress conditions. Peppermint (Mentha piperita) is considered as one of these medical plants and belongs to the Lamiaceae family. The essential oils and extracts of this plant are mainly made up of menthone, menthol and methyl acetate. Peppermint is traditionally used as an antiseptic, antispasmodic, mild tonic, antimicrobial. Materials and Methods A total of 240 one-day-old broilers (Ross 308) were distributed to 8 treatments with 5 replications/treatment based on a randomized block design. Experimental diets consisted of base diet without feed additive and under standard temperature conditions (negative control), base diet without feed additive and under heat stress conditions (positive control), positive control supplemented with 28 mg/kg virginiamycin, 28 mg/kg probiotic protexin, 1 g/kg vitamin C, 1 g/kg vitamin E, 250 and 500 mg/kg peppermint extract, respectively. House temperature was initially set at 28°C for the second week and then reduced by 0.5°C per day until a temperature of 22°C was achieved at the end of the fourth week and then maintained constant thereafter. To induce heat stress, room temperature was raised to 34◦C during 10 AM to 16 PM from 15 to 42 days of age. A 23:1h light to darkness lightening regimen was followed throughout the experimentation period. Body weight gain and feed intake were recorded for days 10, 24 and 42 of age and data were used to calculate feed conversion ratio (FCR). At the end of the experiment (day 42), two birds from each replication with a body weight close to cage mean were selected and killed. Individual blood samples were collected form the slaughtered birds and centrifuged at 1800× g for 15 min. The collected sera samples stored at -20°C pending biochemical assessments. Concentrations of serum glucose, triglyceride, total cholesterol and lowdensity lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), very-low-density lipoprotein cholesterol (VLDL-C), white blood cells (WBC), red blood cells (RBC), Hematocrit and Hemoglobin were determined by different recommended procedures. To assay the primary and secondary antibody responses against SRBC, 2 birds/replicate were immunized intramuscularly with 0.5 mL 10% SRBC in. Blood samples (1.5 mL/bird) were obtained from the brachial vein at 7d following each injection. Results and Discussion The results showed that the highest feed intake and feed conversion ratio were observed in chickens fed with negative control diets (P <0.05). The greatest body weight was observed in the birds fed with the negative control and diets supplemented with probiotics and vitamin E (P <0.05). Broilers fed with diets containing antibiotics as same as positive control group could increase abdominal fat percentage and serum triglycerides concentration than other treatments (P <0.05). The broilers fed with diets supplemented with all feed additives decreased the heterophils to lymphocytes ratio compared to the positive control group (P <0.05). The probiotics and 500 mg peppermint extract-supplemented diets improved the antibody titer against Newcastle, Gumburo and influenza diseases, as well as anti-SRBC titer, compared to the positive control group (P <0.05). The results of this study are supported by other studies, indicating that the dietary supplementation of probiotic could improve physiological responses and immune system and thus performance of heat-stressed birds. Dietary supplementation of vitamin C is an effective strategy to reduce the harmful effects of heat stress in poultry. The results of previous studies have demonstrated that the antioxidant and inflammatory properties of peppermint contributes to the prevention and treatment of diseases associated with oxidative stress, through removing free radical. Medicinal plants with secondary metabolites have also reported to possess the positive effects on growth performance and thus increasing the immune function. The positive effects of peppermint could be due to its active ingredients such as carvacrol, flavonoids and menthol. Flavonoids with antioxidant effects have protective properties against free radicals. The mucous membrane of the gastrointestinal tract plays an important role in preventing antigens and harmful microorganisms from entering the organ and eliminating them, while also being effective in selective nutrient absorption. The results of the present experiment and the other reports also indicate that dietary supplementation of probiotic and vitamin E and C and peppermint extract improve the immune response and growth performance of broilers and could be account as an alternative to antibiotics. Conclusion In conclusion, a high dose of peppermint (500 mg/kg) was as effective as probiotic, vitamin E and C in alleviating the negative effects of heat stress on growth performance, health and immune function. [ABSTRACT FROM AUTHOR]

In recent years, the application of spore-forming bacteria in probiotic food supplements and medicine have become more interesting due to their stability in stressful condition of production line and gut environment. In the current study, the resistance of Bacillus coagulans and Bacillus subtilis in response to heat stress and simulated gastrointestinal tract was investigated. Moreover, the aggregation and hydrophobicity of cell surface of these strains were evaluated. The results showed a survival rate of more than 80% for both species after enduring heat stress and undergoing simulated gastrointestinal conditions. In addition, Bacillus coagulans showed a higher autoaggregation and coaggregation ability compared to Bacillus subtilis. In addition, both probiotic species presented a high tendency toward adhering to the hydrocarbon solvents like chloroform and ethyl acetate. This study was a continuation of previous studies conducted with the aim of developing and optimizing functional edible coating for the production of probiotic rock candy (Nabat) using spore-forming probiotic bacillus, to ensure the survival and effectiveness of the strains. [ABSTRACT FROM AUTHOR]

Abstract Background and Objective: This study was performed to investigate some quantitative characteristics and quality of hyssop under heat stress and nitrogen fertilizer. Materials and Methods: The experiment was conducted as a split-plot in a completely randomized block design with six planting dates and three replications in 2017-2018. The main factor was different levels of nitrogen fertilizer: 0, 50, 100 and 150 kg.ha-1 and sub-factor was planting dates between 30-day periods from October 17 to March 25. Results: Increasing nitrogen fertilizer at the level of 150 kg/ha resulted in the increase of 18.1%, 39.5%, 20.1%, 43.3% and 47.2% in flowering top-branch length, flowering top-branch weight, plant height, biomass yield and total essential oil yield, respectively, compared to not consumption. The highest yield of total essential oil (36051 g.ha-1) was obtained in T1N4, which was 89.7% higher than T4N1. Increasing ambient temperature in the range of 25–40 °C linearly led to decline of top-branch length, top-branch weight and biomass decreased but decreased essential oil yield in the above temperature range was fitted as a quadratic function (R2 = 0.86). Heat stress on delayed sowing dates T3, T4, T5 and T6 reduced the essential oil yield compared to the sowing date T1 by 30.5%, 70.3%, 66.4% and 39.3%, respectively. Conclusion: The application of nitrogen fertilizer increased the studied traits. To reduce the effect of heat stress and achieve optimal yield, are recommended the hyssop planted from 25 October to 25 November and are used 150 kg.ha-1 of nitrogen fertilizer in the subtropical region of Jiroft.

Objective Temperature is a critical variable in health and disease. Thermal stressors such as heat stress elicit neuroendocrine responses including activation of the HPA axis .Heat stress is a challenge for animal and human society. It has been shown that brain monoaminergic system is changed during acute and chronic heat stress condition. Commercial and domestic poultry are very susceptible animals to the heat stress. High environmental temperature led to heat stress condition and had negative effect on physiological performance. One effect of heat stress is changed molecular and cellular mechanisms. These changes in diencephalon, as an awaking center (thalamus) and autonomic mechanisms center (hypothalamus), have profound physiological performance results. However the goal of experiment was to investigate effect of heat stress on diencephalic BDNF gene expression and blood corticostrone level. Materials and Methods In this experiment, 20 seven-day-old male chicks divided in 1- heat stress group (10 chicks) and 2- control group (10 chicks in normal temperature condition). Heat stress induced by 39 C◦ and continued to 5 hours. Control group temperature was 30 C◦. At the end of 5 hours duration, chicks was anesthetized with Isofluran gas and killed. Blood gathered from jugular vein. Brain dissected and diencephalon was frozen in liquid nitrogen immediately. Blood corticosterone level was measured by ELIZA method, BDNF gene expression assayed by quantitative real time PCR technique with the SYBR green method. Results In this experiment, heat stress significantly reduced diencephalic BDNF gene expression. However, corticosterone level significantly elevated in heat stress exposed chicks. It would be able to say that there is a relation between BDNF gene expression and blood corticosterone concentration. Conclusions These results showed changes in BDNF gene expression during heat stress condition is associated to blood corticosterone level elevation. Taken together, the results showed that a significant relationship between Hypothalamus-Hypophysis- Adernal cortex activity during acute heat stress condition and diencephalic BDNF gene expression as a neuroprotective agent of brain.

Introduction: Determining methods for assessing heat stress in different work environments is one of the major challenges for researchers in this field. The purpose of this study was to validate WBGT index and heat pressure assessment (HPA) by some physiological responses in Iranian South Oil Company. Material and Methods: This descriptive-analytical study was carried out on 154 employees of Kharg, Asalouyeh and Mahshahr oil terminals recruited from three different working conditions including indoor, outdoor and rest environments in the summer. The amount of heat stress in the workplace was evaluated by WBGT index HPA method. To meet this purpose, the environmental parameters i.e., temperature, wet temperature, radiation temperature, relative humidity, water vapor pressure and air flow rate were determined. In addition to the direct reading method by the WBGT meter, ISO 7243 was used to calculate the WBGT index. In order to validate the heat stress indicators, physiological parameters of oral temperature, tympanic temperature and work metabolism were measured. Results: The results of paired sample t-test showed a significant difference between WBGT index and HPA in indoor and outdoor environment (P

Introduction: Many studies have been carried out on the effects of heat stress on cognitive functions, but the results are contradictory. Therefore, this study was conducted to review the effect of heat stress on cognitive functions. Material and method: In this study, all English articles conducted on effect of heat stress on cognitive, perceptual, and psychomotor functions from 1970 to 2018 were reviewed. For this, articles with keywords such as heat strain, heat stress, cognitive function, memory, comprehension, psychomotor, reaction time, mental performance, mood, mental response, error, task performance, fatigue, alertness, hyperthermia, and heat exhaustion in the Scopus, Web of Science, Science Direct, Pub Med, Springer, Wiley Online Library and ProQuest databases were searched. Out of 157 retrieved articles, 39 articles were finally reviewed according to the inclusion criteria. Results: Out of 157 retrieved articles related to the topic, according to the inclusion criteria, 39 articles were finally considered for review. Among this articles, 9 (%23) articles were published before 2000 and 30 (%77) after 2000. Two articles were in athletes, four articles (%10.2) in workers, four articles (%10.2) in students, four articles (%10.2) in military soldiers and twenty-five articles (%64.2) were conducted in ordinary people.Based on the results, heat stress was identified as a detrimental factor for decreased cognitive functions such as reading comprehension, memory, focus, mathematical processing, tracking test, reaction time, perception and decoding text and numeric messages, visual alertness, mental computing, text reading , hidden figures test and verbal fluency. Conclusion: Based on the results of these studies, heat stress has been introduced as a detrimental factor for disrupting cognitive functions, but conclusion based on the results of studies is a systematic method is difficult because many confounding variables such as type of work, exposure time, skill and adaptation plays a big role.

Abstract Background and Aim: heat stress is the most common occupational risk factors and can adversely affect the health and efficiency of the individuals. Exposure to extreme heat in the workplace can cause heat-related illnesses as well as increased risk of accidents and related injuries. The previous Studies have shown that heat stress can lead to some physiological responses and affect cognitive function. But these studies have not reached a clear and definitive conclusion. There have been several studies on the effect of heat stress on heart rate and blood pressure. According to the results of the most studies, heat exposure can increases heart rate, but the results of the researches on the effect of heat exposure on blood pressure are not the same. According to the results of the most studies, heat stress can leads to decrease in cognitive performance; however, some studies have shown that cognitive performance does not change or in some cases increase under heat stress conditions. Due to the differences in the results of the previous studies in this area, further studies are needed to clarify these results. The purpose of this study was to investigate the effect of heat stress on cognitive performance, heart rate and blood pressure of the students. Materials and Methods: In this experimental study, 18 volunteer students (9 girls and 9 boys) from the school of health and safety at the Shahid Beheshti University of Medical Sciences with the mean age of 21.11 year and standard deviation of 1.71 year and body mass index of 23.23 kilogram per square meter and standard deviation of 1.44 kilogram per square meter participated. This study was conducted in the laboratory of heat and humidity control. Each participant was randomly exposed to one of the test conditions with 3 different Wet Bulb Globe Temperature. According to the factorial method, there were six different Wet Bulb Globe Temperature conditions in which the subjects were tested in one of these six states. A total of 54 experiments were performed on the subjects. Before the test, all the participants received written consent and they all became familiar with the stages of the experiment. Prior to the test, the participants completed a questionnaire of the inclusion. The criteria for entering the study included age 20-24, undergraduate education, body mass index (BMI) of 23±2 kg/m2, no cardiovascular and mental illnesses, normal heart rate and blood pressure and no drug consumption. In order to examine the mental health of the individuals, they were asked to complete the General Health Questionnaire, developed by Goldberg (1972), before the test. Those who obtained the total score of 0 to 22 were classified in the group without any symptoms or least limit and included in the study. The participants were asked to have sufficient sleep and rest and a normal diet, without coffee or caffeine, before the test. The subjects were also asked to wear simple linen or cotton clothes with light colors to take into account the effect of Clo on heat stress for all the participants. Unwillingness to continue to cooperate during the test was also considered as an exclusion criterion of the study. After selecting the samples based on inclusion criteria, other interfering factors, including noise and lighting were evaluated and controlled. The lighting equal to 450 lux and noise pressure level equal to 35dB were recorded and controlled. Participants were exposed to three different thermal conditions (Wet Bulb Globe Temperature of 29°C as lower than the exposure limit, Wet Bulb Globe Temperature of 32°C as the exposure limit for the non-acclimatized people to warm environments, and Wet Bulb Globe Temperature of 35°C as more than the exposure limit for the non-acclimatized people) for 30 minutes, and their cognitive performance was evaluated in these three thermal conditions. The relative humidity in all stages of the study was 50%. To provide different temperature conditions, two EFHA2200 model electrical fan heaters, manufactured by ARASTEH, as well as two Beurer humidifiers were used. To measure the relative humidity, the GM8910 humidifier (BENETECH Company, China) was used with a precision of ± %5, and to measure the WBGT index, the digital QUESTEMP10 WBGT meter was used with a sensitivity of about one tenth degree Celsius. All the devices were calibrated before the test. To measure the WBGT index, the device was placed at a distance of about 10 cm from the body of the participants in the waist area (0.7 m), and after about a minute, the numbers shown by the device as a WBGT indicator were read. To assess the effect of heat stress on cognitive performance of the participants, a 2018 Integrated Visual and Auditory Continuous Performance test was used and the scores of attention scales including selective attention, focused attention, divided attention, alternating attention and sustained attention were measured in both visual and auditory domains. The IVA test is a computerized test for sustained attention and response control. The participants were exposed to pseudo-randomly ordered series visual and auditory stimuli of numbers 1 and 2, and they were asked to click the mouse when they saw or heard the number 1. With an initial explanation of how to do the test, the entire test lasted 11 minutes. The IVA results were presented in six primary scales (three response control scales and three scales of attention) in the visual and auditory areas. The response control scales are as follows: (Prudence, Consistency and Stamina). The attention scales are as follows: (Vigilance, Focus and Speed). In order to investigate the effect of heat stress on physiological parameters, blood pressure and heart rate of the individuals was also measured before and after exposure to heat. To Measure the blood pressure and heart rate of the subjects, digital Blood Pressure Monitor was used. Its accuracy for measuring blood pressure was ±3 mmHg and for measuring heart rate was ±%5. SPSS software version 22 was used to analyze the results. To analyze the relationship between heat stress and heart rate, blood pressure and attention scales resulting from the Integrated Visual and Auditory Continuous Performance test, the Generalized Estimating Equations test (GEE) was used. Results: According to the results of this study, with increase in Wet Bulb Globe Temperature, the heart rate of the participants significantly increased in relative to pre-exposure conditions (79.72 beat per minutes with SD of 6.83 in Wet Bulb Globe Temperature of 22°C and 90.05 beat per minutes with SD of 8.71 in Wet Bulb Globe Temperature of 35°C, p0.05). With increasing heat stress, the mean of two scales of in auditory domain including auditory selective attention and auditory alternating attention steadily decreased, and this decrease was significant at the Wet Bulb Globe Temperature of 35°C (p 0.05). Conclusion: The results of this study showed that heat stress has a strong and significant relationship with physiological parameters such as heart rate and systolic and diastolic blood pressure. According to the results of this study, heat stress can increase the heart rate and systolic blood pressure and decrease diastolic blood pressure; so Changes in heart rate and blood pressure can act as a good indicator for the heat strain. Exposure to excessive high temperatures can reduce attention and consequently decrease cognitive performance. One of the limitations of this study was the difficulty of doing it in real work environment. Considering that in industrial and real working environment, many interfering factors such as risk factors of the work environment, family and psychological conditions of the subjects, nutrition, different work shifts and time of sleep and rest can affect the results of the study, it will be difficult to select similar samples that meet all of the requirements of this study. However, studies similar to the present study need to be carried out in industrial environments and real work conditions in order to increase the applicability of the results of study in work environments.

Introduction: This study was designed with the main purpose of examining the compatibility of the two indicators of wet bulb globe temperature (WBGT) and predicted thermal strain (PHS) in assessing the environmental conditions and the heat load imposed on the subjects. Method: In this cross-sectional study, 163 bakers were included in the study. Thermal stress was determined using the WBGT and PHS. At the same time, physiological responses of subjects were recorded, including tympanic temperature, heart rate and mean skin temperature. Finally, the predicted heat strain was evaluated and compared with actual values. Results: Based on the results, the WBGT index is accompanied with an underestimation and PHS with an overestimation, compared to the tympanic temperature. In addition, the WBGT index with the core temperature and the predicted rectal temperature component of the PHS index are the most consistent (kappa value of 0.614 and 0.66, respectively). While the Kappa value is between the amount of water lost and the WBGT index, it indicates a mismatch (Kappa = 0.339). Conclusion: The prediction of heat strains only based on the PHS index cannot reflect the actual heat load on individuals in thermal environments such as bakeries and it is associated with an overestimation. On the other words, this indicator is more suitable for indoor thermal environments, with minimal variation in individual and environmental factors affecting thermal stress

Introduction: Many studies, especially in recent years, have evaluated and controlled the occupational heat stress in Iran using environmental indices. However, so far, no comprehensive study has been conducted to review and classify these studies. Therefore, this study aimed to review and investigate the occupational studies performed by environmental heat stress indices in Iran. Material and method: In the present study, the published articles from 2000 to 2016 were searched using Persian and English keywords including heat stress, heat strain, hot condition, warm condition, occupational health, thermal environment and Iran. Search of articles was performed in databases such as Web of Science, Google Scholar, PubMed, Scopus, Science Direct, SID, Magiran, Civilica, Iran Medex, Barakatkns and Irandoc. In total, 323 articles were found and 134 articles of them, based on the exclusion criteria, were selected and included in this study. Results: Based on the results, most numbers of the studies, with 93.3 percent of the total researches related to published article, have been carried out between years of 2010 to 2016. As well as, most of studies with 61.9 percent were related to the indoor industrial environments. Most of studies were also performed in cities of Isfahan with 31.08 percent, Tehran with 16.89 percent, and Assaluyeh with 11.48 percent, respectively. As well as, WBGT index with 76 percent and the UTCI and PHS indices with 0.6 percent had the highest and lowest usage in all environments and industries, respectively. In addition, the results showed that WBGT index had most usage in industries of melting and casting with 15.7 percent, petroleum with 8.3 percent, and outdoor small occupations with 8.3 percent, respectively. Based on the results, the industries of the refinery, steel, glasswork, melting and casting, mines, and ship repairs have the highest mean values of WBGT index, respectively. Conclusion: The results showed the need to more attention of researchers for conducting studies in outdoor environments, in different cities of Iran, on development and validation of novel heat stress indices, and on implementation and evaluation of control measures in the environments with high heat stress.

To investigate the antioxidant properties of Oxalis corniculata L. leaves powder and compare the effects of its addition with vitamin C on the performance and meat quality of broilers under heat stress conditions, an experiment was conducted in a completely randomized design with four treatments, five replications, and 10 birds per replication. The experimental treatments included the corn-soybean diet as a basal diet (control), basal diet + 250 mg kg-1 vitamin C, basal diet + 0.5% O. corniculata leaves powder, and basal diet + 1% O. corniculata leaves powder. To apply heat stress, the chickens from 25 to 42 days of their age were exposed to 34 ± 2 °C for eight hours a day. The performance traits including feed intake, weight gain, and feed conversion ratio were recorded at the end of the experiment. Also, at the end of the experiment, two birds per replicates were randomly selected and slaughtered to measure the meat quality traits. The total phenolic compounds content in the methanolic extract of O. corniculata was 11.73 mg of gallic acid / g of dry matter. The free radical scavenging activity (DPPH assay) percentage and the amount of vitamin C of this plant were obtained 46.63% and 88 mg/g of dry matter, respectively. The consumption of 1% leaves powder of the plant increased the feed intake and weight of broilers compared to the control (P<0.05). The lowest feed conversion ratio was observed in the group of 1% leaves powder of the plant and vitamin C (P<0.05). The highest water holding capacity and meat moisture was observed in the broilers fed with O. corniculata leaves powder compared to the control (P<0.05). All the treatments reduced the cooking loss and dripping loss of meat compared to the control (P<0.05). According to the results of this experiment, the basal diet + 250 mg kg-1 vitamin C and basal diet + 1% O. corniculata leaves powder treatments could improve the growth performance and some meat quality parameters of broilers under heat stress conditions. [ABSTRACT FROM AUTHOR]

Background and Objective: Inappropriate atmospheric conditions are harmful factors that cause particular problems in certain seasons (summer or winter). The occupation of confectionery in the regions like Ilam causes severe problems due to the heat generated by the nature of the work (synthetic heat-generating processes) and the heat resulting from the climatic conditions in the region. Exposure to excessive heat, in addition to disrupting the physiology and health of the individuals that may cause many diseases and complications, also affects their efficiency and safety. One of the indices of heat stress is the WBGT index, confirmed by various national and international organizations and institutions as the standard method for measuring heat stress. WBGT index engages important environmental factors directly or indirectly in its computational structure. The Discomfort Index (DI) has been recommended for more than four decades along with the WBGT index for the evaluation of warm environments. Today, the oral temperature is used to determine the heat stress and strain. In addition, oral temperature is one of the important parameters for the validation of indices. Therefore, in order to prevent the occurrence of heat stress complications in occupational environments, a study was conducted to determine the amount of heat stress in the employees of confectionery workshops in Ilam city, so as to identify the factors affecting the heat stress of workers and to provide recommendations for the reduction of these risk factors and to create a healthy working environment. Methods: This descriptive-analytical study was carried out on 104 workers in 35 confectionary workshops in summer of 2017. The sample size was selected based on census method. Prior to the study, the workers were monitored through medical records and interviews, and, two of them did not qualify for inclusion in the study. Measurement of the study variables was performed at the hottest work hours (10 to 14), once for each worker, in the worst workstation (nearest to the heat source). In the present study, four groups of occupations, i.e. workers of oven, mixer, flattener, cleaning and packaging, three types of ovens, i.e. layered, winch and furnace, and three productions of wet and dry pastry, cake and French bread, Baghlava and Ka’ak. Assessment of heat stress was performed by the WBGT (based on ISO7243 standard) and the DI indices. Metabolism and activity of workers were calculated according to the ACGIH standard. Also, the working pattern was 75% of the work-25% of the rest, and according to ISO 9920, the clothing insulation coefficient in WBGT calculations was 0.6 clo. Along with the environmental parameters such as dry bulb temperature, natural wet bulb temperature, globe bulb temperature, relative humidity and dew point temperature, the oral temperature of the workers was measured by a digital medical thermometer. Finally, data analysis was performed using SPSS v.22 and statistical tests of Kolmogorov-Smirnov, Mann-Whitney, Kruskal-Wallis, one-way ANOVA and Pearson correlation were performed. Results: Findings of this study showed that the mean of WBGT index in the workers of oven, mixer, flattener, cleaning and packaging was 33.66±3.96, 29.58±3.05, 31.73±3.61 and 29.87±2.4. Also, this index was 30.94±3.86, 34.14±3.89, and 32.2±2.91 for the winch (wet and dry pastry), layered (cake and French bread), and furnace (Baghlava and Ka’ak) ovens (products). These results show that the amount of heat stress in working with the oven and the cake and French bread product (layered oven) was more than others. Kruskal Wallis tests and one way ANOVA showed a significant difference between the mean of WBGT and DI indices with job variables, type of oven and products (p

Background: Outdoor workers are vulnerable to heat stress and climate change due to their occupational and environmental conditions. Short-term exposure to extreme heat (acute exposure) can lead to rise the core body temperature, which it may directly cause heat related illnesses such as mild rash, cramps, heat exhaustion and heat stroke. It is reported that long-term chronic exposure to heat leads to chronic kidney diseases, cardiovascular diseases, and mental health problems. The vulnerability consists of three components including sensitivity, exposure, and adaptability. According to the third assessment report of the intergovernmental panel on climate change (IPCC), the defiition of vulnerability is the degree to which a system or an individual is sensitive to, or unable to adapt to the adverse effects of Heat Stress and Climate Changes. Sensitivity is the physical capacity of workers to be affected by a hazardous agent like the heat. Sensitive is an intrinsic and internal factor that indicates how the person is vulnerable to heat stress. Individual risk factors in heat stress may decrease the individual’s tolerance to heat stress. The ability of system to cope with climate changes and adapt to extreme heat to reduce the risks and consequences resulted from these conditions is called adaptive capacity. Adaptation leads to reducing the vulnerability and increasing heat tolerance. Adaptive capacity is definedas“Theabilityof asystemtoadjusttoclimatechange, to moderate potential damages, to take advantage of opportunities, or to cope with the consequences”. Therefore, it should be necessary to reduce the level of vulnerability through providing the control programs and strategies. Since there are no national laws, regulations, guidelines to protect outdoor workers against heat stress in the country, only the relevant policy in this area is the permissible occupational exposure limit. Therefore, the present study aimed to develop a comprehensive operational program to reduce the vulnerability of outdoor workers to heat stress and climate change. The results of this study can be very effective in decision making of the macro-management as well as planning of control measures in the country. Also, the program presented in this study can be helpful for organizations in charge of health and safety such as the Ministry of Health and Medical Education and the Ministry of Cooperatives, Labor and Social Welfare (which are responsible for maintaining, protecting and promoting the health of the workforce). Methods: According to the objective of the study, which was the development and implementation of an operational plan to reduce the vulnerability of outdoor workers to stress and climate change, several technical panels and brainstorming sessions were held with the cooperation of the Institute for Environmental Research, Tehran University of Medical Sciences by eminent experts in the fields of industrial hygiene, environment engaging in Medical Sciences University, Department of Environment and Ministry of Health and Medical Education during the 2014-2016. The main components of the vulnerability, the areas and strategies for application of an operational program to reduce the effects of exposure to heat stress and climate changes in outdoor workplaces were taking into account in the meetings. Also, the Delphi technique (due to the lack of access to some of the professors and executives directors), the study of text books and articles have also been used in this study. Delphi, as an effective and highly flexible technique, is used to achieve consensus or forecast future events. It is a proper method to collect the opinions of experts, who cannot easily meet each other due to geographical distance. Using Delphi as a research method is useful when there is no integrated knowledge about a specific issueorproblem. Results: According our finding, six main components including general plans and policies (16 Strategies), prevention programs (6 Strategies), conservation programs (11 Strategies), training programs (11 Strategies), management planning (14 Strategies) and research and future study programs (11 Strategies) were proposed in the form of 69 strategies with three goals: reduction of sensitivity, reduction of exposure levels and increase of compatibility. Conclusion: The proposed program and strategies in present study, can be used to prepare guidelines for work in hot environments. Our results can be of great help to the occupational health and safety -related organizations such as the Iranchr('39')s Ministry of Health and Medical Education and Ministry of Cooperatives, Labour, and Social Welfare for planning and providing preventive procedures and control measures, in order to take effective action to maintain and improve employeeschr('39') workplace health. Should be noted that the development and implementation of the mentioned policy require the cooperation of all members including employers, health and safety committee, supervisors and employees.

Background and aims: Nowadays, global warming and climate change have become one of the controversial topics that have an impact on the health of individuals and the threat to human life. In recent decades, particular attention has been paid to the issue of environmental change and its impact from different perspectives. Many studies have been conducted to study these effects (generally from a non-occupational perspective) around the world. But from a job standpoint, the probable effects of global warming on occupational health are under reached, although its trend is growing. Outdoor workers are one of the most vulnerable groups of people directly affected by global warming. Climate change and global warming can cause many health problems, one of the most important of which is the development of thermal stresses and related disorders in outdoor occupational exposures. Iran is a large country with very wide climatic diversity, with 35. 5% of it in complete arid, 29.2% of the arid, 20.1% of the semi- arid, 5% of the Mediterranean and 10% of the Wet climates in the country. Thus, more than 82% of the territory of the country is located in the arid and semi-arid region of the world. The average rainfall is 250 mm, less than one third world-wide (860 mm), and its dispersion degree is very high in the country. Increasing the average temperature can lead to warmer days and longer and more frequent heat waves. This, in turn, can increase the risk of heat-related diseases such as heat stroke, heat cramp, heat exhaustion, etc., and even in advanced cases, causes death. These effects are likely to be different in different regions, based on the sensitivity of the community, the amount and duration of exposure, as well as the ability of individuals to adapt to temperature variations. So, the main objective of this study was to investigate temperature changes in different climates of Iran in the coming decades in order to obtain an adequate understanding of the heat stress state in outdoor environments. Methods: The environmental parameters required in this study were air temperature (ta), wet temperature (tw) and relative humidity (RH) which are determined by calibrated devices. At the same time, the WBGT temperature index was also measured and recorded using the calibrated WBGT meter, Casella model. All measurements were carried out at three times throughout the day, including 9 am, 12 noon and 3 pm, indicating the initial, mid, and final hours of shift work in the studied environments in the country, respectively. In order to cover this study throughout the country, and taking into account all the existing climates in the country, with the exception of areas with cold- dry and cold- humid climates, which often include the western and northwest parts of the country, 9 climatic zones in each country were selected in that country. A total of 495 measurement series of environmental parameters were carried out in nine climates (55 measurements per each climate). All measurements were done in outdoor settings such as open pit mines, asphalt and road workers, farmers, cement factories and shipbuilding industries. The selection of industries and locations was also performed randomly. Selected sites in this study, each representing different climates in the country, included cities of Ahwaz, Bandar Abbas, Rasht, Gorgan, Kerman, Yazd, Sari, Qom and Mashhad. The Arc / GIS 8.0 software was used to generalize the data from a meteorological station to other weather stations in a similar climatic zone, and the environmental parameter values ​​measured at each station were similar to the other meteorological stations in the same climate were linked. Thus, in the GIS information layers, different climate zones were determined using two parameters of air temperature and humidity. In this process, the gathered spot data was converted into regional data. In addition, the long-term data for each climate zone (between 1965 and 2010), including the minimum and maximum daily air temperature, rainfall and sunshine, were used to generalize the data to other similar climate zones. Finally, using the weather behavior of previous periods at the studied stations, the weather conditions between 2011 and 2100 using the LARS-WG model and a coupled atmosphere-ocean general circulation model (HadCM3) for each of the 9 weather stations, simulations were performed. Then, according to the goal of the study that emphasizes the stress on outdoor work space, this model evaluates climate change in different regions based on daily maximum and minimum temperatures up to 2100 at 25-year intervals. Results: Based on the results, a temperature increase with different intensities is expected in the next decade. In addition, the pattern of variations was almost the same for all stations studied. On the other hand, slight changes in the average daily minimum and maximum air temperature are observed until 2025. These changes were not very different in the spring and summer. After that, by 2075, the temperature increase is observed with a gentle slope, and thereafter, until 2100, no significant changes are observed for most of the stations. However, there is a significant increase in the average daily minimum and maximum temperatures in summer compared to spring. According to the results of the model, the highest temperature rise in 2075 is expected in most parts of the country. In general, the mean and standard deviation (M ± SD) of expected changes at minimum and maximum temperatures were 1.34 ± 1.41 °C and 1.29 ± 1.40 °C for spring and 2.38 ± 2.44 °C and 2.34± 2.48 °C for the summer, respectively. The respective values, regardless of the season (spring or summer) were1.86 ± 2.05 °C and 1.82 ± 2.07 °C for the minimum and maximum temperature changes, respectively. In general, it can be said that the average temperature of different climates of Iran will increase by about 2 °C until 2100. The results of the thermal stresses in the nine areas studied, which were simultaneously with other environmental parameters of the study, showed that in the spring, except for climatic zones 5 and 6, which are related to the cities of Yazd and Bandar Abbas, at least at 12 noon, no significant stress was observed in any of the affected areas. However, over time and approaching the afternoon (until around 3:00 pm), many other climatic zones, including sites 2, 7 and 8 (cities such as Ahvaz, Sari and Gorgan) , In addition to sites 5 and 6, will be in a stressed state even in the afternoon. In other words, in almost all parts of the country, especially in the middle and end of shift work, there is heat stress in the summer or even in many areas in the spring. The lowest WBGT index was 17.5 ± 0.99 °C for the early hours of the morning (in the spring and in the northern regions of the country) and the maximum is 35.10 ± 0.55 °C for noon and evening hours (in the summer and in the southern regions of the country). In general, the analysis of temperature differences and heat stress in different parts of the country also shows that parts of the country that have the greatest impact on climate change are the central and southern regions of the country. These findings clearly show that many workers, especially those working in outdoor environments, are currently in an environmentally unfavorable condition (regardless of any possible increase in temperature as a result of climate change) and they suffer from the dangers and complications of thermal stress. Considering the objectives of the study as well as the obtaining results about climate change during the current century (about 2 °C), it can be expected that the trend of changes in thermal stress in the country will also change in most parts of the country similar to the trend of temperature changes in the country in the coming decades. Conclusion: Climate change caused by global warming and, as a result, increased heat stress, especially for outdoor workers, is a very important issue that has relatively similar effects in different parts of the world. Based on the obtained results, an increase of about 2 degrees Celsius to the average temperature of the air, regardless of the changes in other parameters affecting heat stress such as relative humidity, air velocity and radiant temperature, can put several parts of the country under thermal stress conditions. In other words, the different areas and external environments that are currently in terms of acceptable thermal stress status will suffer from heat stress due to climate change and rising temperatures in the coming decades. For example, it is expected that the northwest, west, and northern and central parts of the country will be exposed to heat stress. In addition, most of the southern and central parts of the country, which are currently in heat stress, will be in a worse situation. Therefore, preventive interventions such as open outdoor environments design, shading in industrial areas, designing cool rest areas to reduce exposure to heat, developing work and rest programs, attention to acclimatization to the environment and observing public health programs, can play an important role in reducing the adverse health effects of climate change and the increase in temperature on exposed outdoor workers.

Background and aims:Heat stress is a occupational major problem in Iranshahr city, which can lead to undesirable effects on health and reduce the productivity of people. This article examines this problem and its effects in different parts of Iran's Hospital in this city. Methods:This cross-sectional study was performed on 181 employees of different departments of a hospital in different periods of 9 am and 12 noon. Two WBGT and DI indices were used to investigate heat stress and thermal discomfort. Also to survey of human productivity Hersey and Goldsmit scale was used. Finally to study of relationship between the WBGT and DI with human productivity and its subscales, Pearson correlation was applied. Results:The results showed that at 9 am the highest average of WBGT and DI indices were obtained for installation powerhouse1 and generator2 units, respectively.And the lowest amount of these indices were for pharmacy and administrative units. Also at 12 noon, the highest amount of these indices was for the powerhouse2 and generator 2 units respectively.At the same time, the lowest amount of these indices were obtained for NICU and pharmacy respectively.The results of Pearson correlation coefficient showed that WBGT and DI indices had a reverse and significant relationship with human productivity (P

Introduction: Scrotal hyperthermia has been known as a cause of male infertility. Testicular heat-stress even for a single short period can induce destruction in testicular tissue and spermatogenesis disturbances. This study was conducted to determine the protective effects of royal jelly (RJ) against testicular damage and spermatogenesis following heat-stress induction in male rats. Materials & Methods: In this experimental study, 48 male rats were randomly divided into 8 groups (n=6( including: 1- Control, 2- RJ (100 mg/kg BW/day; PO), 3 , 4 and 5 heat-stressed (43, 39, and 37 for 20 min per day, respectively) and 6, 7 and 8 heat-stressed along with RJ (43, 39, and 37 for 20 min per day, respectively plus RJ at a dose of 100 mg/kg BW/day; PO). Heat-stress was induced through immersion of experimental rat scrotums in a water bath. After 48 days, the animals were sacrificed and left testes were removed and fixed. Five-micrometer testicular tissue sections were prepared and studied using a light microscope. Findings: The data revealed that diameter and germinal epithelium height of the seminiferous tubules, thickness of basement membrane, number of spermatogenic and Sertoli cells, and testicular weight decreased significantly (p

Introduction: Working in hot and harsh weather conditions can cause heat related diseases and in some cases, even can lead to death. Risk assessment of heat stress in these environments is of particular importance. As there are many factors that could affect the heat stress, therefore, an index should be applied that could properly reflect the effect of all of these factors. Material and Method: Initially a five-member expert team was established. Then, the weight of each variable was determined by the fuzzy analytical hierarchy process (FAHP) method. In next step, five work stations of the casting process evaluated applying fuzzy TOPSIS (FTOPSIS) method and the risk of heat stress prioritized in these stations. Lastly, the Pearson’s correlation coefficient was used to determine correlation between the results of proposed method with WBGT index. Result: The weights of three main variables including task characteristics, working environment, and worker characteristics was determined as 0.279, 0.526, and 0.195. The risk priority of the five work stations including, stocking, melting furnace, pouring and casting, polishing, and warehousing was established as S1= 4, S2= 2, S3= 1, S4= 3, and S5= 5. The Pearson’s correlation coefficient between the similarity index (CCi) and WBGT was 0.97. Conclusion: From three main variables that can affect the heat stress, “Working Environment” has main impact in the risk assessment process; therefore, the most efforts must be focused on controlling this variable. The proposed method in this study has the capability of concurrent quantitative and qualitative assessment of factors that could affect the heat stress and can minimize the uncertainties in the risk assessment process relying upon the fuzzy sets.

The physiological and biochemical traits of 12-year-old olive trees cvs. Zard and Direh were studied in response to thermal fluctuations during growing seasons in Tarom region (Zanjan province, NW of Iran) for two successive years 2017-2018. The experiment was carried out as split plots in time based on complete randomized block design (cultivar as main plot and time as sub-treatment). The sampling and data recording were performed during four different time including; May, July, August and September correspond to the 28, 45, 44 and 36 °C, respectively. The results showed that the photosynthesis rate of cv. Direh during stressful high temperature conditions at July, and in compare to May decreased two times more than cv. Zard. Cultivar Zard, in spite of its high photosynthesis rate, showed lower amount of cumulative shoot growth and dry weight, which was mainly due to the large amount of fruit yield efficiency in this cultivar. The proline accumulation in leaf tissue of 'Direh' failed to play a constructive role in developing higher heat stress tolerance in this cultivar. The soluble carbohydrates concentration in 'Zard' was higher than 'Direh' during all period of study. In general, cv. Zard had more tolerance to increased heat stress during growth season. [ABSTRACT FROM AUTHOR]