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La biología térmica es uno de los aspectos más necesarios para entender la distribución y los patrones de actividad de las especies, sobretodo de los organismos ectotermos. El presente estudio aporta información sobre temperatura corporal de seis ofidios ibéricos y temperatura ambiental para el lugar donde habitan. Para tres de las especies, Coronella girondica (Daudin 1803), Macroprotodon brevis (Günter 1862) y Hemorrhois hip­pocrepis (Linnaeus 1758), estos son los primeros datos publicados en España. En el caso de Natrix maura (Linnaeus 1758) los datos de este estudio incluyen temperatura tanto en medio acuático como en medio terrestre. En total se han obtenido 31 registros de temperatura corporal y 30 registros de temperatura ambiente. También se aportan datos sobre temperatura corporal y ambiental de Malpolon monspessulanus (Hermann 1804) y Zamenis scalaris (Schinz 1822). Thermal biology is one of the most necessary aspects in understanding the distribution and activity patterns of species, above all of ectothermal organisms. The present study provides data on body temperature of six Iberian ophidians and the environmental temperature of the place they inhabit. For three species, southern smooth snake Coronella girondica (Daudin 1803), western false smooth snake Macroprotodon brevis (Günter 1862), and horse-shoe snake Hemorrhois hippocrepis (Linnaeus 1758), these are the first data published in Spain. In the case of Natrix maura (Linnaeus 1758), the present data include its temperature on land as well as in aquatic environments. In total, 31 body temperature records and 30 ambient temperature records were obtained. Additionally, data is given on body and environmental temperature for the ophidian species Malpolon monspessulanus (Hermann 1804) and Zamenis scalaris (Schinz 1822).

Growth hormone receptor knockout (GHRKO) mice are smaller, long living, and have an increased metabolic rate compared with normal (N) littermates. However, it is known that thermoneutral conditions (30–32°C) elicit metabolic adaptations in mice, increasing the metabolic rate. Therefore, we hypothesized that environmental temperature would affect the expression profile of different adipose tissue depots in GHRKO mice. For this, N (n = 12) and GHRKO (n = 11) male mice were maintained at 23 or 30°C from weaning until 11 months of age. RNA sequencing from adipose tissue depots (epididymal—eWAT, perirenal—pWAT, subcutaneous—sWAT, and brown fat—BAT) was performed. Thermoneutrality increased body weight gain in GHRKO mice, but not in N mice. Only a few genes were commonly regulated by temperature in N and GHRKO mice. The BAT was the most responsive to changes in temperature in both N and GHRKO mice. BAT Ucp1 and Ucp3 expression were decreased to a similar extent in both N and GHRKO mice under thermoneutrality. In contrast, eWAT was mostly unresponsive to changes in temperature. The response to thermoneutrality in GHRKO mice was most divergent from N mice in sWAT. Relative weight of sWAT was almost 4 times greater in GHRKO mice. Very few genes were regulated in N mice sWAT when compared with GHRKO mice. This suggests that this WAT depot has a central role in the adaptation of GHRKO mice to changes in temperature.

Despite the commonly held belief that reptiles are immune to extreme temperatures, global warming is predicted to result in the loss of 40% of all reptile species by 2080. In order to understand th...

El objetivo fue evaluar el grado de infestación natural por Rhipicephalus microplus, así como determinar su correlación con factores climatológicos y su efecto sobre la ganancia de peso en bovinos doble propósito. Se utilizaron 31 bovinos cruzados, Bos taurus x Bos indicus, de ambos sexos, con una edad promedio de 307 días. El conteo de garrapatas semi-repletas (4.5 a 8.0 mm de diámetro) y el pesaje de los animales se realizaron cada 28 días. El conteo de garrapatas se realizó desde la cabeza hasta la base de la cola, abarcando miembros anteriores y posteriores, así como la región ventral de los animales. Las variables de respuesta estudiadas fueron número de garrapatas semi-repletas y ganancia de peso promedio del animal. En julio el número promedio de garrapatas por animal fue mayor (P0.05) el número de garrapatas. La ganancia de peso disminuyó 34 g (P

Eimeriosis of farm animals is one of the most widespread parasitic diseases in the world. In the conditions of the steppe zone of Ukraine Eimeria perforans is more common in rabbits and E. arloingi in sheep and goats. Study of factors which influence the development of these protists on the soil surface is one of the major challenges for veterinarians working for large livestock companies and fighting against eimeriosis. Environmental temperature is able to change the speed of sporulation of oocysts Eimeria. Five values of temperature (15, 20, 25, 30, and 35 °C) were used in a laboratory experiment in vitro. At 15 °C, the process of sporulation of E. arloingi and E. perforans in 100% of cases ended on the eighth day. With increase in temperature to 35 °C, the duration of sporulation decreased to three days. When the temperature was 30 °C the completion of sporulation was observed in more than 50% of the oocysts of E. arloingi on the second day, and for E. perforans on the third day. High-speed sporulation at elevated temperatures under conditions of global warming can result in the increasing spread of eimeriosis among wild and domestic animals.

Background and Aim: In modern scientific literature presents an understanding that African swine fever (ASF) ASF virus (ASFV) is remarkably stable in the environment, and carcasses of the pigs which were died after ASF, play a key role as ASFV reservoir. The aim of this study was to evaluate the possibility of the ASFV (different isolates) survival in bodies of dead animals, bones, remnants of bone marrow, residual organ matrix in natural conditions. Materials and Methods: Skeletons of ASFV infected pigs which were died and left/abandoned in forests or buried in Armenia at diverse time points and locations had been excavated and examined for the presence of ASFV genome by real-time polymerase chain reaction (PCR) assay and for infection abilities through in vitro (hemadsorption test and infection in porcine lung macrophages) as well as by intramuscular infection in healthy pigs. Results: Current exploration showed that in several samples (with different times of exposure) of excavated skeletons had been detected the presence of the virus gene (p72) using real-time PCR. However, in none of these porcine samples, infectious ASFV could be isolated. Data obtained by real-time PCR at frequent intervals indicated the presence of the virus gene (p72), especially within the case of the acute form of the disease. This can be explained by the highest levels of the virus during the latter case mentioned above. Conclusion: ASFV seems to be very sensitive to environmental temperature. The best place for ASFV long-term survival in the natural environment is bone marrow from intact big tubular bones (like femur or tibia) of buried carcasses. In artificial "graves," complete bones with not destructed bone marrow can preserve the virus gene (p72) for a very long time (more than 2 years). Infectious particles in underground conditions survive not so long: In complete bones with not affected bone marrow, possible presence of the virus for several months.

Effective monitoring of mammal species is critical to their management. Thermal cameras may enable more accurate detection of nocturnal mammals than visual observation with the aid of spotlights. We aimed to measure improvements in detection provided by thermal cameras, and to determine how these improvements depended on ambient temperatures and mammal species. We monitored small to medium sized mammals in central Australia, including small rodents, bettongs, bilbies, European rabbits, and feral cats. We conducted 20 vehicle-based camera transects using both a spotlight and thermal camera under ambient temperatures ranging from 10°C to 35°C. Thermal cameras resulted in more detections of small rodents and medium sized mammals. There was no increased benefit for feral cats, likely due to their prominent eyeshine. We found a strong relationship between increased detections using thermal cameras and environmental temperature: thermal cameras detected 30% more animals than conventional spotlighting at approximately 15°C, but produced few additional detections above 30°C. Spotlighting may be more versatile as it can be used in a greater range of ambient temperatures, but thermal cameras are more accurate than visual surveys at low temperatures, and can be used to benchmark spotlight surveys.

The fabrication of protein hydrogels consisting of different properties and functional motifs is critical in the development of protein-based materials for biomedical applications. Here, we report the design and characterization of a triblock protein polymer, CEC, composed of two different self-assembling domains derived from elastin protein (E) and coiled-coil protein (C), photopolymerized with a NHS-diazirine (D) crosslinker into a CEC-D hydrogel. The optimal photocrosslinker concentration and exposure time is determined to fabricate a free-standing hydrogel. Upon increasing the concentration of the CEC-D monomer and environmental temperature, the CEC-D hydrogel's conformation decreases in helical content from 58.0% to 44.8% and increases in β-content from 25.9% to 38.1%. These gels experience 55 ± 6% protein erosion from the free-standing gel in 13 days as the gel films gradually decrease in size. The swelling ratio of 12 ± 1% denotes that the gel has a swelling ability comparable to other protein hydrogels. These photocrosslinked CEC-D hydrogels can be employed for drug delivery with high encapsulation and 14 ± 2% release of curcumin into the supernatant in a week long study. Overall, the photocrosslinked CEC-D hydrogels exhibit stability, swelling ability, and sustained release of drug.

Environmental temperature directly controls the rate at which ectotherms grow and develop. The growing degree-day metric (GDD, °C·day) scales time by temperature to create a thermal time scale relevant to ectothermic organisms. Here we assess the ability of GDD to model size-at-age and duration-to-moult in 15 datasets (9 size-at-age, 6 duration-to-moult) comprising 7 species of lobsters and crabs. We applied generalized linear models to assess the ability of GDD vs. “calendar” time to explain growth and development observations within and across trials. Best-fit models included GDD with fewer parameters in 6 of 9 size-at-age and 5 of 6 duration-to-moult datasets and a better fit to the data in 6 of 9 size-at-age datasets. Our results show that the individual growth of lobster and crab species can be modelled using thermal time models. Such models can be used to identify thermal tolerance limits, predict growth under varying temperature conditions and disentangle temperature effects from those of other factors affecting individual growth and development, resulting in improved growth models for field conditions including fisheries management.

Article Details: Received: 2020-10-22 | Accepted: 2020-11-27 | Available online: 2021-01-31 https://doi.org/10.15414/afz.2021.24.mi-prap.131-134 A prerequisite for the successful pig breeding isthe achievement of high reproductive performance, which can be influenced by several environmental factors. Therefore, the aim of our research was to assess the impact of the season, microclimatic indicators and technology of housing of the lactating sows on the number of the weaned piglets in the litter. The experiment was performed on a production farm in Slovakia and a total of 800 litters were evaluated. The results have shown that the season had a statistically significant effect on the number of the weaned piglets ( p

The structure of mosquito larvae breeding habitats were studied at Onicha Igbeze and its environ in Onicha Local Government Area of Ebonyi State, Nigeria. The study was carried out by identifying the larvae habitat, the structure, quality, measuring the temperature, pH and counting the number of larvae per breeding habitats. Larvae breeding habitats of different structures and quality were identified at twenty locations within the study area. The temperature of the breeding habitats ranged from 27.10oC to 31.90oC. Highest mean pH (8.50) was recorded at the breeding sites located at Isu Road 6. The anopheline mosquitoes were predominant among the two larvae types identified with the highest number (213 individual larva) recorded at Isu Road 2. Simple linear model performed depicted that larvae density increased with the habitats temperature and decreased with pH. Meanwhile, the study showed that the presence of larvae breeding habitats and an increase in environmental temperature favoured the breeding of mosquito larvae and could be setbacks to the fight against malaria.

High ambient temperature is one of the major causes of economic losses in the livestock industry. The poultry industry is an integral part of the livestock industry. It faces severe losses due to heat stress (HS). The adverse effects of HS can be seen on production performance, body temperature, intestinal health, appetite hormone regulation, immune responses and oxidative characteristics. It is important to monitor these parameters to identify the HS possessions during rearing so that timely action can be taken to minimize the adverse effects of high ambient temperature. Furthermore, the application of productive methods on farms is equally important. Several strategies have been suggested by researchers. Providing a suitable environment with selective rearing systems along with proper ventilation and hygiene is the basic requirement for all types of livestock reared for animal protein. Supplementation of appropriate feed additive could be useful for improving intestinal absorption and minimizing adverse effects of HS. Selection for breeding heat resistant birds also provide merits for improving the germplasm of the strains. Early age thermal conditioning also helps in developing resistance for HS. The most recent advancement is the supplementation of active substances during incubation. It is expected that these methods may have a potential impact on the poultry industry for creating thermotolerance in the newly hatched chicks. This review highlights the major issues concerning chicken health and suggests the measures to be adopted following the increase in environmental temperature.

The thermal comfort region for greatest animals is between 4 °C and 25 °C and when environmental temperature surpasses 25°C, animals suffer from heat stress conditions. Over 50% of the cattle population is located in the tropics and it has been appraised that heat causes severe economic loss in approximately 60% of the dairy farms around the world.In tropical and subtropical countries, the climatic characteristic is the major constraint on animal productivity. In severe heat stress, growth, milk yield, milk composition and reproductive traits are reduced as a result of the extreme changes in biological functions affected by heat stress. Heat stress disturbs the steady-state concentrations of free radicals, resulting in both cellular and mitochondrial oxidative damage. Although heat stress causes a decline in dry matter intake, the cow's energy and protein requirements in hot environments increase. This review provides an overview of the impact of heat stress on farm animals.

The Peruvian Andean Plateau, one of the main production areas of native varieties of Chenopodium quinoa, is exposed to abrupt decreases in environmental temperature, affecting crop production. Plant-growth-promoting rhizobacteria that tolerate low temperatures could be used as organic biofertilizers in this region. We aimed to bioprospect the native psychrotolerant bacteria of the quinoa rhizosphere in this region that show plant-growth-promoting traits. Fifty-one strains belonging to the quinoa rhizosphere were characterised; 73% of the total could grow at low temperatures (4, 6, and 15 °C), whose genetic diversity based on DNA amplification of interspersed repetitive elements (BOX) showed 12 different profiles. According to the 16S rRNA sequence, bacterial species belonging to the classes Beta-and Gammaproteobacteria were identified. Only three (6%) isolates identified as nonpathogenic bacteria exhibited plant-growth-promoting activities, like IAA production, phosphate solubilization, growth in a nitrogen-free medium, and ACC deaminase production at 6 and 15 °C. ILQ215 (Pseudomonas silesiensis) and JUQ307 (Pseudomonas plecoglossicida) strains showed significantly positive plant growth effects in aerial length (about 50%), radicular length (112% and 79%, respectively), and aerial and radicular mass (above 170% and 210%, respectively) of quinoa plants compared with the control without bacteria. These results indicate the potential of both psychrotolerant strains to be used as potential organic biofertilizers for quinoa in this region. © 2020, Canadian Science Publishing. All rights reserved.

The temperature‐size rule (TSR) describes the inverse relationship between organism size and environmental temperature in uni‐ and multicellular species. Despite the TSR being widespread, the mechanisms for shrinking body size with warming remain elusive. Here, we experimentally test three hypotheses (differential development and growth [DDG], maintain aerobic scope and regulate oxygen supply [MASROS] and the supply–demand [SD] hypothesis) potentially explaining the TSR using the aquatic protist Colpidium striatum in three gradually changing and one constant temperature environment crossed with three different nutrient levels. We find that the constant and slowly warming environments show similar responses in terms of population dynamics, whereas populations with linear and fast warming quickly decline and show a stronger temperature‐size response. Our analyses suggest that acclimation may have played a role in observing these differences among treatments. The SD hypothesis is most parsimonious with the data, however, neither the DDG nor the MASROS hypothesis can be firmly dismissed. We conclude that the TSR is driven by multiple ecological and acclimatory responses, hence multicausal.

Thermoregulation is the maintenance of the core body temperature. The regulation of body temperature is one of the most important functions of the nervous system. Nucleus raphe magnus, as a central circuit coordinates the homeostatic response and maintains body temperature during environmental temperature challenges and adjusts body temperature during the inflammatory response and behavioral states and in response to decreasing energy homeostasis. Our aim in this review is the understanding of thermoregulation by raphe magnus in mammals. This review summarizes the basic concepts of thermoregulation and subsequently assesses the physiological responses to cold stress, including skin blood flow control, sweating, sympathetic-derived cutaneous vasoconstriction and peripheral thermoregulatory control in brown adipose tissue. © 2020, Iranian Society of Physiology and Pharmacology. All rights reserved.

Ectothermic animals are especially susceptible to temperature change, considering that their metabolism and core temperature are linked to the environmental temperature. As global water temperatures continue to increase, so does the need to understand the capacity of organisms to tolerate change. Sheepshead minnows (Cyprinodon variegatus) are the most eurythermic fish species known to date and can tolerate a wide range of environmental temperatures from − 1.9 to 43.0 °C. But little is known about the physiological adjustments that occur when these fish are subjected to acute thermal challenges and long-term thermal acclimation. Minnows were acclimated to 10, 21, or 32 °C for 4 weeks or acutely exposed to 10 and 32 °C and then assessed for swimming performance [maximum sustained swimming velocity (Ucrit), optimum swimming velocity (Uopt)] and metabolic endpoints (extrapolated standard and maximum metabolic rate [SMR, MMR), absolute aerobic scope (AS), and cost of transport (COT)]. Our findings show that the duration of thermal exposure (acute vs. acclimation) did not influence swimming performance. Rather, swimming performance was influenced by the exposure temperature. Swimming performance was statistically similar in fish exposed to 21 or 32 °C (approximately 7.0 BL s−1), but was drastically reduced in fish exposed to 10 °C (approximately 2.0 BL s−1), resulting in a left-skewed performance curve. There was no difference in metabolic end points between fish acutely exposed or acclimated to 10 °C. However, a different pattern was observed in fish exposed to 32 °C. MMR was similar between acutely exposed or acclimated fish, but acclimated fish had a 50% reduction in extrapolated SMR, which increased AS by 25%. However, this enhanced AS was not associated with changes in swimming performance, which opposes the oxygen-capacity limited thermal tolerance concept. Our findings suggest that sheepshead minnows may utilize two distinct acclimation strategies, resulting in different swimming performance and metabolic patterns observed between 10 and 32 °C exposures.

Bemisia tabaci has many biotypes, and has become one of the main pests on vegetables, flowers, cotton and other crops, seriously influencing the safe production of crops.Temperature has a great influence on the survival, development, reproduction and behavior of Bemisia tabaci, which can affect the change of body temperature and metabolism of B. tabaci. It needs certain water to maintain normal life activities, such as digestion, nutrition transportation, and temperature regulation. There is a suitable humidity range for the growth and development of B. tabaci in different development stages. High humidity or drought have a great impact on the growth and development of B. tabaci, especially on its survival or reproduction. At the same time, the environmental temperature and humidity are the important factors that influence the geographical distribution and population change of B. tabaci.

Neptunea cumingii is an important nutrition-rich economic species in China. Juveniles of N. cumingii suffer from high mortality at low temperatures, which has proved a limiting factor in raising seedlings in artificial habitats. Previous research has shown that N. cumingii displays aggregation behavior in response to adverse environmental changes. Therefore, we determined the effects of temperature, food, size of juvenile snails, substratum type, and density of juvenile snails on the aggregation behavior of N. cumingii. Results show that, at a low (4°C) or a high (22°C) temperature, juvenile snails adjusted to the inhospitable environment by exhibiting increased aggregation behavior. However, their aggregation behaviors differed at these two temperatures. There was no significant difference in the aggregation rate, but the typical aggregation size was larger at 4°C than at 22°C. At 10°C or 16°C, aggregation behavior of juvenile snails reduced. Aggregation increased in the satiation treatment at 10°C and 16°C. Small-sized juveniles tended to have higher aggregation rates (92.22%) and a larger typical aggregation size. More juveniles were distributed in the bottom of shaded substrata. A larger typical aggregation size or higher density significantly reduced the mortality of juvenile snails at a low temperature (4°C). These results broaden our understanding of gastropod aggregation behavior and can be used to develop and improve commercial breeding strategies and resource recovery for N. cumingii.

En production porcine, la réduction de l’adiposité des carcasses au profit de la teneur en maigre obtenue par l’amélioration génétique et l’évolution des conditions d’élevage, a entraîné l’apparition de défauts de qualité des tissus adipeux. La qualité de ces tissus ne peut guère être améliorée par les technologies de transformation, elle dépend des caractéristiques des tissus à l’abattage, celles-ci étant déterminées par les conditions d’élevage des animaux en interaction avec leur type génétique. Les composantes nutritionnelle, organoleptique et technologique de la qualité des tissus adipeux sont fonction de leur composition chimique : teneurs en lipides et en eau, importance de la trame conjonctive, et de la nature des acides gras constitutifs des lipides. Ainsi, tout facteur intrinsèque ou extrinsèque à l’animal entraînant une variation de composition du tissu adipeux modifie en conséquence la qualité de ce tissu. La composition du tissu adipeux varie selon la localisation anatomique, l’adiposité globale de la carcasse et le type sexuel. Parmi les facteurs d’élevage, l’alimentation, en particulier la nature des acides gras ingérés, la supplémentation du régime alimentaire en vitamine E ou en minéraux, l’administration de promoteurs de croissance (hormone de croissance, béta-agonistes) ainsi que la température d’élevage influencent les propriétés de la fraction adipeuse de la carcasse. Les effets des facteurs d’élevage sur les caractéristiques des tissus adipeux du porc et leurs relations avec la qualité sont relativement bien établis. La maîtrise de la qualité des tissus adipeux est donc maintenant accessible, et ne dépend plus que de l’importance relative accordée à la qualité dans les coûts de production, au sein de la filière porcine., In pig production, genetic selection and rearing conditions have greatly improved body composition towards a higher lean meat content and a lower fat deposition. However, a degradation of adipose tissue quality has been observed. Because fat tissue quality can hardly be improved by technological processing, it depends strongly on adipose tissue characteristics at slaughter, which are influenced by rearing and genetic factors. Nutritional, sensory and technological fat qualities are determined by tissue chemical composition:lipid and water contents, characteristics of connective tissue, and fatty acid composition, Therefore, any intrinsic or extrinsic factor that alters the composition of adipose tissues influences fat quality, Thus, anatomical location, carcass fatness, sex, feeding level, fatty acid composition of the diet, supplementation with vitamin E or minerals, growth promotants (pST, beta-agonists), and environmental temperature have been shown to influence fatty tissue traits. Effects of rearing factors on composition and quality of pig adipose tissue are now well established, Thus, control of pig fat quality is now attainable, and depends mainly on the relative importance given to quality in the overall cost of pig production.

Acoustic signals are an essential part of the multi-modal systems of conspecific communication among insects. The patterns of abiotic factors effects on their communication parameters are of great interest for prognostic purposes in current climatic instability and for practical application in order to manage their populations. The aim of this study was to reveal the dependence of the parameters of acoustic signals produced by bark beetle Polygraphus proximus, an aggressive alien stem pest on the environmental temperature. Male stridulatory signals were recorded in seven temperature settings (5–35 °C), and changes in their temporal parameters were evaluated under laboratory conditions. The obtained results allowed us to reveal the pattern of temperature dependence of signals produced by P. proximus. More than half of the insects were found to actively stridulate at 5 °C. Raising temperature caused an increment in chirp rate that continued to increase up to 30 °C. Further temperature increase led to suppression of signaling in most of the tested males. The obtained results showed a number of patterns of temperature effect on the parameters of acoustic signals which might be universal for representatives of different bark beetles genera with various stridulatory apparatus types.

Rift Valley fever virus (RVFV) causes severe disease in domestic ungulates (cattle, goats, and sheep) and a febrile illness in humans (with ∼1% case fatality rate). This virus has been spreading geographically, and there is concern of it spreading to Europe or the Americas. Environmental temperature can significantly affect the ability of mosquitoes to transmit an arbovirus. However, these effects are not consistent among viruses or mosquito species. Therefore, we evaluated the effect of incubation temperatures ranging from 14°C to 30°C on infection and dissemination rates for Culex tarsalis and Aedes taeniorhynchus allowed to feed on hamsters infected with RVFV. Engorged mosquitoes were randomly allocated to cages and placed in incubators maintained at 14°C, 18°C, 22°C, 26°C, or 30°C. Although infection rates detected in Cx. tarsalis increased with increasing holding temperature, holding temperature had no effect on infection rates detected in Ae. taeniorhynchus. However, for both species, the percentage of mosquitoes with a disseminated infection after specific extrinsic incubation periods (4, 7, 10, 14, 17, or 21 days) increased with increasing incubation holding temperature, even after adjusting for the apparent increase in infection rate in Cx. tarsalis. The effects of environmental factors, such as ambient temperature, need to be taken into account when developing models for viral persistence and spread in nature.

Insecticide-treated bed nets reduce malaria transmission by limiting contact between mosquito vectors and human hosts when mosquitoes feed during the night. However, malaria vectors can also feed in the early evening and in the morning when people are not protected. Here, we explored how the timing of blood feeding interacts with environmental temperature to influence the capacity of Anopheles mosquitoes to transmit the human malaria parasite Plasmodium falciparum. In laboratory experiments, we found no effect of biting time itself on the proportion of mosquitoes that became infectious (vector competence) at constant temperature. However, when mosquitoes were maintained under more realistic fluctuating temperatures, there was a significant increase in competence for mosquitoes feeding in the evening (18:00), and a significant reduction in competence for those feeding in the morning (06:00), relative to those feeding at midnight (00:00). These effects appear to be due to thermal sensitivity of malaria parasites during the initial stages of parasite development within the mosquito, and the fact that mosquitoes feeding in the evening experience cooling temperatures during the night, whereas mosquitoes feeding in the morning quickly experience warming temperatures that are inhibitory to parasite establishment. A transmission dynamics model illustrates that such differences in competence could have important implications for malaria prevalence, the extent of transmission that persists in the presence of bed nets, and the epidemiological impact of behavioural resistance. These results indicate that the interaction of temperature and feeding behaviour could be a major ecological determinant of the vectorial capacity of malaria mosquitoes. Laboratory and modelling studies show that temperature conditions can enhance the capacity of malaria to infect mosquitoes that feed in the evening compared with those that feed at midnight or in the morning.

The effects of temperature in winter-spring (average 17.0 °C) and spring-summer (average 23.0 °C) seasons on the transmission and latent period of maize bushy stunt phytoplasma (MBS-phytoplasma) and corn stunt spiroplasma (CSS) (Spiroplasma kunkelii) caused by the corn leafhopper, Dalbulus maidis (DeLog and Wolcott) (Hemiptera: Cicadellidae) were evaluated in two experiments in a screenhouse in Sete Lagoas, Minas Gerais State, Brazil. Approximately 200 mollicute-free adults of D. maidis were confined on popcorn (Zea mays L. cv. IAC125) plants infected with spiroplasma and the same number of mollicute-free leafhoppers were confined on plants infected with phytoplasma. They remained on the source plants for a 6 d acquisition access period (AAP). Next, leafhoppers were fed healthy popcorn seedlings. Transmission tests were performed with one leafhopper per seedling for each mollicute, with 12 replicates, at 12, 20, 30, 40 d since the first day of AAP. In addition, at 40 d, one leafhopper with phytoplasma and another with spiroplasma were confined together on 24 popcorn seedlings. The inoculation access period (IAP) was 3 d. The temperature was recorded daily during the experimental periods. In Experiment 1, during the 40 d latent period, only 41.6% and 58.3% of plants, respectively, exposed to phytoplasma or to both mollicutes presented MBS-phytoplasma symptoms. In Experiment 2, during the 20 d latent period, some popcorn plants presented MBS-phytoplasma (16.7%) and CSS (33.3%) symptoms, whereas almost 100% of plants at the 30 and 40 d latent period presented disease symptoms. Plant symptoms and results from PCR tests indicated that MBS-phytoplasma was more tolerant to low temperatures than S. kunkelii.

Whole-organism function is underpinned by physiological and biological processes, which respond to temperature over a range of time scales. Given that environmental temperature controls biological rates within ectotherms, different experimental protocols are needed to assess the ability of organisms to withstand extreme weather events versus gradual temperature change. Here we emphasize the importance of time in shaping ecological and evolutionary processes, and as an experimental parameter that is key when interpreting physiology studies reporting thermal limits. We discuss how acute and chronic thermal performance is underpinned by mechanisms operating at different time scales — resistance, acclimation, and adaptation. We offer definitions of common physiological and biological temperature metrics and identify challenges inherent to compiling the wealth of historical temperature limit data now available into meta-analytic frameworks. We use a case study, data across temperate fishes, to highlight that false positives may occur when differences in the thermal tolerances of species are in fact due to experimental protocols. We further illustrate that false negatives can arise if researchers fail to recognize differences in thermal limits of species emerging from macrophysiological approaches that are due to biological mechanisms. We strongly advocate for the careful design, interpretation, and reporting of experimental results to ensure that conclusions arising from data synthesis efforts are grounded in theory.

Cold environmental temperatures during exercise and recovery alter the acute response to cellular signaling and training adaptations. Approximately 3 wk is required for cold temperature acclimation to occur. To determine the impact of cold environmental temperature on training adaptations, fitness measurements, and aerobic performance, two groups of 12 untrained male subjects completed 1 h of cycling in 16 temperature acclimation sessions in either a 7°C or 20°C environmental temperature. Fitness assessments before and after acclimation occurred at standard room temperature. Muscle biopsies were taken from the vastus lateralis muscle before and after training to assess molecular markers related to mitochondrial development. Peroxisome proliferator-activated receptor-γ coactivator 1α ( PGC-1α) mRNA was higher in 7°C than in 20°C in response to acute exercise before training ( P = 0.012) but not after training ( P = 0.813). PGC-1α mRNA was lower after training ( P < 0.001). BNIP3 was lower after training in the 7°C than in the 20°C group ( P = 0.017) but not before training ( P = 0.549). No other differences occurred between temperature groups in VEGF, ERRα, NRF1, NRF2, TFAM, PINK1, Parkin, or BNIP3L mRNAs ( P > 0.05). PGC-1α protein and mtDNA were not different before training, after training, or between temperatures ( P > 0.05). Cycling power increased during the daily training ( P < 0.001) but was not different between temperatures ( P = 0.169). V̇o2peak increased with training ( P < 0.001) but was not different between temperature groups ( P = 0.460). These data indicate that a 3-wk period of acclimation/training in cold environmental temperatures alters PGC-1α gene expression acutely but this difference is not manifested in a greater increase in V̇o2peak and is dissipated as acclimation takes place. NEW & NOTEWORTHY This study examines the adaptive response of cellular signaling during exercise in cold environmental temperatures. We demonstrate that peroxisome proliferator-activated receptor-γ coactivator 1α mRNA is different between cold and room temperature environments before training but after training this difference no longer exists. This initial difference in transcriptional response between temperatures does not lead to differences in performance measures or increases in protein or mitochondria.

National bodies in Great Britain (GB) have expressed concern over young stock health and welfare and identified calf survival as a priority; however, no national data have been available to quantify mortality rates. The aim of this study was to quantify the temporal incidence rate, distributional features, and factors affecting variation in mortality rates in calves in GB since 2011. The purpose was to provide information to national stakeholder groups to inform resource allocation both for knowledge exchange and future research. Cattle birth and death registrations from the national British Cattle Movement Service were analyzed to determine rates of both slaughter and on-farm mortality. The number of births and deaths registered between 2011 and 2018 within GB were 21.2 and 21.6 million, respectively. Of the 3.3 million on-farm deaths, 1.8 million occurred before 24 mo of age (54%) and 818,845 (25%) happened within the first 3 mo of age. The on-farm mortality rate was 3.87% by 3 mo of age, remained relatively stable over time, and was higher for male calves (4.32%) than female calves (3.45%). Dairy calves experience higher on farm mortality rates than nondairy (beef) calves in the first 3 mo of life, with 6.00 and 2.86% mortality rates, respectively. The 0- to 3-mo death rate at slaughterhouse for male dairy calves has increased from 17.40% in 2011 to 26.16% in 2018, and has remained low (

The purpose of this study was to evaluate heat stress as a model to induce gastrointestinal leakage in broiler chickens. On the day of hatch, 320 chicks were allocated into 8 environmental chambers, 4 thermoneutral (TN) and 4 continuous heat stress (HS). Each chamber was divided into 2 pens containing separate feeders and water jugs (8 replicates per treatment, 20 birds/pen). The environment was established to simulate production setting as best possible for the first 21 D. A gradual reduction of temperature from 32°C to 24°C with relative humidity at 55 ± 5% was adopted for the first 21 D. At the time of HS, the HS groups were exposed to 35°C from Day 21 to 42, while thermoneutral ones were maintained at 24°C from Day 21 to 42. Chickens were equipped with a Thermochron temperature logger for continuous monitoring of core body temperature. The environmental temperature and relative humidity were continuously recorded. Fluorescein isothiocyanate–dextran (FITC-d) was orally gavaged to 2 chickens/replicate (n = 16) randomly selected on days 21, 28, 35, and 42. After 1 h of oral gavage, blood samples were collected to determine the passage of FITC-d. Tibias were removed from all chickens to evaluate break strength only on 21 D and 42 D (before HS and at the end of the trial). Performance parameters were evaluated weekly from 21 D to the end of the trial. Body temperature was significantly (P

Fatty acids (FA) are the primary metabolic fuel for many organisms and the fundamental component of membranes of all living organisms. FAs can be saturated (SFA), monounsaturated (MUFA), or polyunsaturated (PUFA). PUFA are not synthesized by most animals and are considered as essential nutrients. We examined the effect of climate on the saturation level of polar (mostly membranal) and neutral lipids in the body of the Oriental hornet (Vespa orientalis) from two extreme climatic zones: Mediterranean high elevation; and hot arid desert. In contrast to previous reports, the environmental temperature was shown to affect the hornet colonies’ thermal environments. The hornets nonetheless maintained their colony temperature within a narrow range. Analyses of the hornets’ unsaturation levels of polar and non-polar body lipids revealed caste differences: gynes and males contained less unsaturated lipids than workers. However, there were no differences in the respective castes between the two different climate zones tested. Experimentally manipulating the diet of queenless hornet colonies to a high Omega-3 diet (salmon) or a high Omega-6 diet (crickets) had only a minor effect on the worker-born males’ lipid composition. Although salmon-fed males had a higher Omega-3 content than cricket-fed ones, the proportion of these fatty acids was still low (below 1%). Cricket-fed males had significantly higher levels of Omega-6 than salmon-fed males. Our data show that the specific lipid composition of the hornet body is highly regulated and deficient in essential PUFA, even under different climates or high Omega-3 or Omega-6 PUFA diet. PUFA, especially Omega-3, is considered to have a beneficial effect on physiological processes. Our finding that these FA, when common in the diet, are almost absent in the body raises questions about how they affect animals’ physiology.

Lambic beers are beers produced through spontaneous fermentation and maturation in wooden barrels. The production process of lambic beers differs from the production processes of lagers and ales in process technology, environmental parameters, and the use of specific raw materials. Moreover, every lambic beer production process is unique in terms of microbiology and flavor formation because of its dependence on the spontaneous inoculation of microorganisms coming from the environmental air (contacting the open coolship and other brewery equipment) and the inner surfaces of the barrels. Several factors influence the inter- and intraspecies microbial successions during lambic beer wort fermentation and maturation and determine the final quality of the end products. The possibility to manually acidify the wort, the presence of species-specific metabolic traits, the environmental temperature, the co-occurrence of lactic acid bacteria and acetic acid bacteria, as well as yeasts, and the quality of the wooden barrels all determine the progress and outcome of the lambic beer production process. Further alterations in quality and flavor of lambic beers can be achieved by blending practices and additional bottle refermentations. This results in a vast array of lambic-derived beer products (e.g., gueuze) with complex taste and aroma profiles and specific characteristics, which separate them from most other commercially available beers.

The mouse-deer or chevrotains are the smallest of the ungulates and ruminants. They are characterized by a number of traits which are considered plesiomorphic for the Artiodactyla order. The objective of this study was to examine sleep in the lesser mouse-deer (Tragulus kanchil), which is the smallest in this group (body mass < 2.2 kg). Electroencephalogram, nuchal electromyogram, electrooculogram, and body acceleration were recorded in four adult mouse-deer females using a telemetry system in Bu Gia Map National Park in Vietnam. The mouse-deer spent on average 49.7 ± 3.0% of 24 h in non-rapid eye movement (NREM) sleep. REM sleep occupied 1.7 ± 0.3% of 24 h or 3.2 ± 0.5% of total sleep time. The average duration of REM sleep episodes was 2.0 ± 0.2 min, the average maximum was 5.1 ± 1.1 min, and the longest episodes lasted 8 min. NREM sleep occurred in sternal recumbency with the head held above the ground while 64.7 ± 6.4% of REM sleep occurred with the head resting on the ground. The eyes were open throughout most of the NREM sleep period. The mouse-deer displayed polyphasic sleep and crepuscular peaks in activity (04:00–06:00 and 18:00–19:00). The largest amounts of NREM occurred in the morning (06:00–09:00) and the smallest before dusk (at 04:00–06:00). REM sleep occurred throughout most of the daylight hours (08:00–16:00) and in the first half of the night (19:00–02:00). We suggest that the pattern and timing of sleep in the lesser mouse-deer is adapted to the survival of a small herbivorous animal, subject to predation, living in high environmental temperatures in the tropical forest undergrowth.

A study was conducted to screen out the low-temperature tolerant Boro rice seedlings from November 2012 to January 2013 for facing the upcoming rice production challenge in Northwest Bangladesh. The experimental time was characterized by a prevailing low environmental temperature of below 15°C. Five rice cultivars (V1: BR-2; V2: BR-16; V3: Pariza; V4: Minicate; V5: BRRI dhan 50) were selected for the study. The leaf proline, chlorophyll content and total carotenoid content were investigated. The V2 (BR-16) seedling synthesized the higher leaf proline (1.228 g·g-1) at a low temperature than those of other tested cultivars. Again, the highest amount of chlorophyll-a (3.957 g·g-1), chlorophyll-b (2.118 g·g-1), chlorophyll-a/b ratio (3.6754 mg·g-1) and total chlorophyll (5.051 g·g-1) was measured in V2 (BR-16). The maximum total carotenoid (1.213 g·g-1) was also observed in V2. In this experiment, the V2 (BR-16) showed comparatively better potentiality to survive at low temperatures (below 15°C) than other varieties.

Seasonal and daily fluctuations in environmental temperature can affect the fitness of endotherms by increasing metabolic costs and energetic requirements. Consequently, some species adopt strategies that function to minimize costs, including minor circadian fluctuations in body temperature (Tb) and facultative reductions in Tb, known as heterothermy. The geographic and taxonomic patterns of variation in Tb are poorly-known, especially in the Neotropics. We investigated the diurnal variation in Tb of small birds inhabiting high-elevation Neotropical montane forests which must cope with predictably cool nighttime temperatures. Two-thirds of the individuals we measured lowered their Tb at night, and changes were greater when differences between daytime and nighttime ambient temperatures were greater. Our study expands the taxonomic and geographic scope of documented thermoregulatory flexibility in birds by demonstrating that even in the Neotropics, some montane birds may routinely adopt energy-saving physiological strategies. Such data are important to understanding and interpreting biogeographic patterns and behavior of tropical birds.

Hot environments can affect feed intake and lactation, and the subsequent unavailability of important micronutrients to the newborn piglet can impair piglet growth, reduce the viability of newborn piglets and limit their subsequent performance. This work addresses the effects of hot environments (summer season) upon the reproductive performance of sows during gestation and lactation as well as on the serum levels of vitamins and the concentration of immunoglobulins in their litters in comparison with the winter season. Fourteen sows were evaluated over 100 ± 2 days of gestation in each season. The temperature and humidity index (THI) was used as an indirect measure of heat stress during gestation. The reproductive performance, milk yield, and body condition of the sows were recorded. The concentrations of vitamin E and vitamin A in piglets and in sow serum, colostrum, milk and feed were determined by HPLC; immunoglobulins were assessed by an ELISA. The THI index indicated that animals were subject to heat stress only in during the summer. Although the effect was not significant, there were a lower number of piglets at birth and at weaning and the milk yield in summer compared with winter. There was no difference (p > 0.05) in the body condition of sows between seasons. Season had an effect (p < 0.05) on the vitamin A concentration of postpartum sow serum (0.29 μg/mL in winter vs 0.21 μg/mL in summer) and on the vitamin E concentration before birth (2.00 μg/mL in winter vs 0.90 μg/mL in summer). Vitamin E in milk was higher (p < 0.05) in winter than in summer (2.23 vs 1.81 μg/mL). Serum levels of vitamins A and E in piglets at birth were lower (p < 0.05) in winter than in summer. The concentrations of immunoglobulins (IgG and IgA) in colostrum and milk were similar between seasons (p > 0.05), but the IgA in piglet serum was higher in winter than in summer (p < 0.05). High temperatures produced heat stress in sows, which affected certain aspects of production that can be translated into economic losses for this sector.

As sessile organisms, plants have evolved numerous strategies to acclimate to changes in environmental temperature. However, the molecular basis of this acclimation remains largely unclear. In this study we identified a tRNAHis guanylyltransferase, AET1, which contributes to the modification of pre-tRNAHis and is required for normal growth under high-temperature conditions in rice. Interestingly, AET1 possibly interacts with both RACK1A and eIF3h in the endoplasmic reticulum. Notably, AET1 can directly bind to OsARF mRNAs including the uORFs of OsARF19 and OsARF23, indicating that AET1 is associated with translation regulation. Furthermore, polysome profiling assays suggest that the translational status remains unaffected in the aet1 mutant, but that the translational efficiency of OsARF19 and OsARF23 is reduced; moreover, OsARF23 protein levels are obviously decreased in the aet1 mutant under high temperature, implying that AET1 regulates auxin signaling in response to high temperature. Our findings provide new insights into the molecular mechanisms whereby AET1 regulates the environmental temperature response in rice by playing a dual role in tRNA modification and translational control.

The aim of this research was to evaluate the vegetative growth, flowering and some attributes of physicochemical quality in blackberry ‘Tupy’ fruits cultivated in Chihuahua, Mexico. The study was carried out in San Juanito and La Finca with twenty-five replications per site. The length and number of sprouts, flowering, total soluble solids (TSS), total titratable acidity (TTA), pH, colour, ascorbic acid (AA), total anthocyanins (TA), total phenols (TP) and antioxidant capacity (AC) were evaluated. San Juanito presented the blackberry plants with the longest sprout length (169.71 cm), but their number was similar to La Finca, which also showed statistical significance with respect to the minimum temperature range (-2.9 and -1.2 °C), which manifested itself in less accumulation of cold units (658) and degree days (886). The flowering event started at 108 Julian days (April 19) for San Juanito completely evading the occurrence of late frosts, while La Finca maintained a 10% risk. The fruits harvested in the Finca showed the highest content of TA (75.7 mg cyanid-3-glucosid 100 g-1), maintaining the fruit quality without changes for both sites. The results indicate that the environmental temperature conditions of San Juanito are suitable for vegetative growth and floral development, by completely avoiding the occurrence of late frosts and obtaining fruits with quality similar to that harvested in orchards with commercial production.

This study was done to compare the environmental temperature and the effect of feed management on dairy cattle productivity in KUTT Suka Makmur Grati Pasuruan. Primary data were collected by questionare based interview to the farmers at different height areas those were 40 farmers in lowland area and 40 farmers in highland area. Data were analyzed using descriptive statistics and quant itative methods. The results showed that temperatures in the lowlands were higher at around 24oC - 27oC, so cattle experiencing heat stress and the impact was cattle consumed less feed, while the availability of water was limited. In contrast, the highlands temperature was relatively low, about 22oC - 24oC. The cattle in highland was fed with elephant grass with a good nutrient content, so the cattle was able to produced well. Keywords: Dairy Cattle, Environment, Feed Effect, Productivity, Temperature

Species exhibit large diversity in their seasonal metabolic patterns which are traditionally explained by habitat specific seasonal temperature changes and various thermoregulatory adaptations. However, due to seasonal changes in resource abundances, density-dependent, ecological processes can also be important selective forces shaping the evolution of metabolic patterns. In the present theoretical study, the combined effect of environmental temperature and resource availability on the evolutionarily stable metabolic strategies is investigated in a consumer–resource model. Our results suggest that, under a broad range of circumstances, density-dependent mechanisms favor the selection of active metabolic regulation, where the metabolic rate differs from the thermally optimal value. This effect may be temporary, limited only to a brief period at seasonal changes, or permanent depending on the implied energetic cost and the relative timescale of environmental changes as compared to the generation time.

When a prey is perceived and attacked, it may adopt direct anti-predator strategies, such as fleeing and tonic immobility (TI). During this latter, individuals remain in a motionless posture, which may reduce chances of being preyed, but retain close distance to the predator. Alternatively, fleeing increases distance from the threat, while enhancing chances of predation by visually guided predators. Thus, there is a trade-off between these two opposite direct anti-predator strategies. Here, we characterize the balance between these two behaviors in Zabrotes subfasciatus, a beetle that when stimulated displays binary responses: TI or running away. We investigated which factors determine TI frequency, probability, and duration. We examined the roles of period of the day (3 AM, 9 AM, 3 PM, and 9 PM), environmental temperature, sex, body size, and consecutive stimuli (three successive). None of these factors influenced TI duration. However, TI exhibition was higher at 3 PM, with no effects regarding sex or stimulus. As temperature raises, TI probability increases. This is paradoxical because ectothermic animals are expected to present increased locomotive activity under higher temperatures due to metabolic dependence. As far as we know, this is the first report of temperature positive relating to TI, especially in an ectothermic animal. At hotter periods of the day, while visually guided ectothermic animals are more active, Z. subfasciatus TI frequency is higher. As TI success is based on the lack of movement, which triggers killing behaviors of visually guided predators, this association may increase chances of survival against ectothermic predators.

Temperature is crucial for reptiles, also during embryonic development, particularly for species with temperature-dependent sex determination. Under natural conditions, Broad-snouted caiman (Caiman latirostris) eggs are influenced by thermal changes in the interior of the nest related to the external environmental temperature. As nests are subject to variations in temperature and most lab studies on crocodilian incubation have been carried out at constant temperatures, we were interested in determining how temperature fluctuations may affect the development of caiman embryos. We investigated the effects of incubation at constant temperatures (31°C, 32°C, and 33°C) and fluctuating temperatures (31 ± 2, 32 ± 1, and 32 ± 2°C) on the following aspects: incubation period duration, hatching success, sex ratio, total length, and body mass of C. latirostris hatchlings. Eggs incubated at 31°C produced 100% females, those at 32°C produced 71.6% females (however, the sex ratio was nest related), and at 33°C produced 100% males. We found a masculinizing effect when incubation was at 31 ± 2°C compared with a constant 31°C; and temperature fluctuations at 32°C (32 ± 1 and 32 ± 2°C) had a negative effect on hatchlings size and mass, and hatching success compared with constant incubation temperatures of 32°C and 33°C. Finally, the effect of temperature variation during the incubation period on sex ratio, hatching success, and phenotype depends on the mean temperature, as the fluctuation around 31°C affected the sex ratios and incubation period, and the fluctuation around 32°C affected hatchling success and size.

The present work was assumed to evaluate the physicochemical and microbial characteristics of honey containing heat-resistant Bacillus coagulans T11 (HBC) samples. The HBC sample exhibited a Newtonian behavior with higher viscosity rate than the control honey (without B. coagulans T11) sample. The results from chemical analysis revealed that ash, proline, acidity, insoluble solid, pH and electrical conductivity (EC) of HBC sample were more than control honey sample (p

The present study was divided in two different trials. The aim of the first trial was to determine if the thresholds of detection of skatole and indole are achieved in females and in males vaccinated against the GnRF housed in two different type of floors and subject to control or high environmental temperatures. The aim of the second trial was to assess the effect of sire (Duroc crossbreed and Pietrain crossbreed) and heat stress on the concentration of skatole and indole in entire males. In the first trial, the animals subjected to heat stress on a concrete floor were found to be dirtier and to present higher skatole and indole concentrations than did animals from the control treatment in 100% slatted floors. In the second trial, although the animals were dirtier when subjected to high temperatures, no effect of the temperature was found in skatole/indole concentrations. The Duroc pigs were dirtier and had higher skatole and indole concentrations than did Pietrain pigs. It is concluded that even females or vaccinated males can reach values of skatole/indole close to the thresholds of sensory detection under conditions of dirtiness and heat stress. However, the relationship between heat, dirtiness and skatole/indole concentrations in fat were not confirmed in trial 2 using entire males. info:eu-repo/semantics/acceptedVersion

The purpose of this study was to evaluate the effect of environmental temperature and relative humidity on algae biofouling that often occurs on porous and rough fired brick surfaces. Brick samples were chosen since their common use on building facades. Accelerated growth tests were performed under different relative humidities and different temperatures. Results showed the effects of different temperature conditions in terms of algae growth delay and reduction of the covered area. All the relative humidity conditions tested substantially showed no growth from an engineering standpoint. The modified Avrami’s law succeeded in modelling the biofouling under the different environmental conditions.

The Peregrine Falcon (Falco peregrinus) breeds locally in the Guerrero Negro wetland complex, Baja California Sur, Mexico, but the most recent investigation of their breeding ecology in this wetland area was in 1998. Our objectives were to update the information on the reproduction of Peregrine Falcons in Guerrero Negro and to evaluate the relationship of reproductive parameters with the environmental temperature, rainfall, and nest substrate (natural or artificial). From 2012 to 2016 we surveyed for Peregrine Falcon nests, and monitored them from February to May each year. We recorded the type of nest substrate (natural or artificial) and the nest contents (eggs, nestlings, or fledglings) at every visit. Pooled across years, we recorded 34 reproductive events that produced 42 fledglings. On average per year, there were 6.8 ± 1.6 egg-laying pairs, and 4.4 ± 1.8 were successful, with a productivity of 1.23 ± 0.06 fledglings/egg-laying pair. Monthly mean air temperatures and rainfall had no effect on breeding parameters; however, there were significant relationships with type of nest substrates. On average, we found falcons had greater nesting success and productivity on artificial substrates (83 ± 15% and 1.91 ± 0.12 fledglings/egg-laying pair) than on natural substrates (36 ± 21% and 0.36 ± 0.21 fledglings/egg-laying pair). Compared to the 1998 estimate, the number of egg-laying pairs in Guerrero Negro has more than doubled (from four to nine); this wetland area currently holds the largest number of breeding pairs along the Baja California Peninsula.

The pattern of sleep and circadian activity of the lesser mouse-deer (Tragulus kanchil) that is the smallest (body mass between 1.5 and 2.2 kg) representative of the basal group (Tragulidae) of even-toed ungulates which evolved 40–50 Ma were studied. In naturalistic conditions, a total of 30 days of full-day video of the animal behavior and 15 days of 24-h polysomnographic data were collected in 6 animals. The mouse-deer were active less than 20% of 24 h and were quiescent during 60–80% of the remaining time. Slow wave sleep (SWS) accounted for on average 49.7 ± 3.7% of 24 h and paradoxical (rapid eye movement, REM) sleep accounted for 1.7 ± 0.3% of 24 h. During the majority of SWS (87.0 ± 4.4%) the eyes were open. The most of SWS and REM sleep occurred during the daytime hours (9 a.m. to 4 p.m.) and in the first half of the night (8 p.m. to 2 a.m.); the animals were most active during twilight hours (4–6 a.m. and 6–7 p.m.). We suggest that the main features of sleep in the mouse-deer are largely determined by ecological factors, including environmental temperature and predation, as well as the size and physiology of the mouse-deer.

Background and Aim: Metabolism and environment are closely related. Under high ambient temperature (HTa), dairy cows may have different energy metabolism during summer and winter. The present study was carried out to investigate the effect of HTa on the milk yield and blood concentration of beta-hydroxybutyrate (BHBA) and glucose at the herd level. Materials and Methods: One large dairy farm in Thailand with more than 100 crossbred Holstein cows milked each month was selected. The first experiment was performed on non-lactating cows to determine the normal daily concentrations of blood BHBA and glucose. Under the HTa condition, there was no significant change in blood BHBA and glucose concentrations. The second experiment was performed using a prospective cohort clinical design to demonstrate the seasonal effect on milk yield and blood BHBA as an indication of energy metabolism at the herd level. Results: The temperature and humidity index for the winter (78.1±0.5) and summer (83.4±0.7) periods differ significantly. The average milk yield during the winter period was 17.8% higher than during the summer period. The reduction of body condition score (BCS) during early lactation was significant in the winter cows. Both higher milk yield and lower BCS in the winter cows suggested a state of negative energy balance. However, there was no difference in blood BHBA and glucose concentrations between winter and summer cows. The effect of HTa on insulin signaling appeared to be a counterbalancing factor for the ketogenic status. Based on the present results, it would be interesting to further investigate the incidence of subclinical and clinical ketosis in a dairy farm under tropical conditions. Conclusion: The present experiment revealed that HTa during summer decreased milk yield in dairy cows fed under tropical conditions. Higher milk yield in winter caused a greater reduction of BCS and suggested a greater negative energy balance. However, there was no seasonal effect on blood BHBA and glucose concentrations.