Search

This study aimed to investigate the effect of zinc oxide nanoparticles in combination with a composite (gelatin/alginate) on the shelf life of white leg shrimp (Litopenaeus vannamei) during 10 days of refrigerated storage. Shrimp were prepared in 5 treatments, including: control (shrimp treated in distilled water), SMS (shrimp treated with sodium metabisulfite solution), composite (shrimp treated in an alginate/gelatin coating), ZnO2.5 [shrimp treated in a composite containing 2.5% ZnO nanoparticles (w/w)], and ZnO5 [shrimp treated in a composite containing 5% ZnO nanoparticles (w/w)]. The results showed that the number of mesophilic aerobic bacteria, Pseudomonas, and lactic acid bacteria in the control sample increased significantly until the end of the storage period, while the samples containing ZnO nanoparticles had significantly lower levels of bacteria. In addition, total volatile base nitrogen, trimethylamine, thiobarbituric acid species, and pH levels in shrimp treated with the nanoparticles were significantly lower than those in the control group (P < 0.05). The highest and lowest changes in texture (springiness and cohesiveness) were observed in the control and treatments containing ZnO, respectively (P < 0.05). The sensory evaluation, texture, and color results were consistent with those of other reported data. However, using an alginate/gelatin coating significantly delays shrimp spoilage during refrigerated storage, and the use of zinc oxide nanoparticles significantly reduces microbiological and chemical spoilage and increases the shelf life of shrimp. [ABSTRACT FROM AUTHOR]

The supply of food for the world population that is increasing is one of the concerns of governments. The Food and Agriculture Organization of the United Nations assessment shows that the aquaculture industry could help meet food needs for human communities. The aquaculture industry also relies on providing a feed of high quality. Minerals are one essential component of an aquatic diet. Chromium (Cr) is a trace element that finds the form of Cr+3 (trivalent) and Cr+6 (hexavalent) in nature and food items. Studies show that exposure to Cr waterborne have toxicity effects on fish. However, oral exposure to Cr has a different impact on fish. Cr is usually involved in the metabolism of fats, carbohydrates, proteins, growth function, enzyme functions, etc. This element could play a significant role in fish nutrition and physiology. Cr as a dietary supplement can improve growth performance and adjust the metabolism of carbohydrates and lipids. However, high concentrations of Cr can be toxic to fish. Although the physiological effects of Cr on aquatic organisms are well known, there are still ambiguities in determining the appropriate concentration in the diet of some species. Maybe, the physiological response of fish depends on the concentration, origin, and chemical composition of Cr, as well as the biological and individual characteristics of the fish. Therefore, it is necessary to estimate the appropriate concentration of Cr in fish diets. This article aims to summarize the available information about the effect of Cr on various physiological indicators and fish growth. Therefore, this information may help to find the appropriate concentration of Cr in the diet. [ABSTRACT FROM AUTHOR]

The effects of carboxymethyl cellulose (CMC) coating incorporated with Shirazi thyme (Zataria multiflora) oil nano emulsion (SNE), in different concentrations (10, 20, and 30 mg/ml), on the melanosis and the quality of Pacific white shrimp (Litopenaeus vannamei) was investigated during 10 days in refrigerated temperature (4 ± 0.5 °C). The results showed that incorporating SNE into CMC could significantly (P < 0.05) improve the microbial and lipid oxidation quality of the shrimp. During storage, the incremewnt of total volatile basic-nitrogen and trimethylamine in the SNEs-treated groups were lower than that of the other groups (P < 0.05). Also, the application of SNEs improved the textural, melanosis, and sensory acceptability of the coated shrimps. However, treating the shrimp with SNE in 30 mg/ml concentration caused an increase in the a* and b* values of samples and a decrease in the acceptability of this group. Hence, the SNE incorporation at lower concentrations (10, 20 mg/ml) into CMC coating could be useful in extending the shelf life of the shrimp during refrigerated storage and could be a substitute for sodium metabisulphite. [ABSTRACT FROM AUTHOR]

This study was conducted to measure concentrations of cadmium (Cd), lead (Pb), arsenic (As), mercury (Hg), copper (Cu), chromium (Cr), and iron (Fe) in blood serum and feces of mugger crocodile (Crocodylus palustris) and in water and sediment of their habitat (Negour site, Chabahar County in Sistan and Baluchistan Province, Iran). Heavy metal contents in crocodile serum and feces, water, and sediments were analyzed by inductively coupled plasma optical emission spectrometry (ICP–OES spectrometer—Spectro Genesis). The highest levels of heavy metals in the mugger crocodile's serum were Fe > Hg > Pb > Cr > Cu > Cd > As, respectively. The total metal concentrations in the feces exhibited the following decreasing order from Fe > As > Pb = Cr > Hg > Cd > Cu. The highest average levels of heavy metals in water were Hg > Fe > As > Pb > Cu > Cr > Cd respectively and As > Fe > Pb > Cu > Hg > Cd > Cr in the sediment of lagoons. A significant difference was observed in the concentration of Fe and Pb between male and female crocodiles. Moreover, correlation analysis indicated significant negative correlations between sex and bioconcentrations of Cd, Fe, Pb, As, and Hg in the serum. In conclusion, this study showed that the environmental conditions of Negour lagoons are not suitable for crocodiles regarding habitat health and water quality. Furthermore, since these lagoons and fish are the most important sources of drinking water and seafood for the residents of the area, contamination of these pools with heavy metals can also threaten people's health. [ABSTRACT FROM AUTHOR]

Exposure to microorganisms such as Yersinia ruckeri can significantly affect bacterial infections in fish. Microplastics (MPs) may predispose fish to infection and act as carriers in pathogen transmission. Therefore, this study is designed to evaluate MPs' effect on damage caused by exposure to Y. ruckeri in rainbow trout. In this study, blood biochemical parameters and hepatic oxidative biomarkers as clinical signs were measured in the fish co-exposed to Y. ruckeri (5 and 10% the median lethal dose (LD50)) and MPs (500 and 1000 mg Kg−1) for 30 days. There were no significant changes in the creatinine, triglyceride, cholesterol levels, and glutamic-pyruvic transaminase activity in the blood of fish infected with Y. ruckeri. In contrast, exposure to MPs had a significant effect on most clinical parameters. The total protein, albumin, globulin, total immunoglobulins, high-density lipoprotein, low-density lipoprotein, cholesterol levels, and γ-glutamyltransferase activity decreased, whereas glucose, triglyceride, and creatinine levels, and glutamic-oxaloacetic transaminase, glutamic-pyruvic transaminase, alkaline phosphatase, and lactate dehydrogenase activities increased in the plasma of fish after co-exposure to MPs and Y. ruckeri. Dietary MPs combined with a Y. ruckeri challenge decreased catalase and glutathione peroxidase activities, and total antioxidant levels. However, superoxide dismutase activity and malondialdehyde contents increased in the hepatocyte of fish co-exposed to MPs and Y. ruckeri. This study suggests that fish exposure to MPs and simultaneous challenge with Y. ruckeri could synergistically affect clinical parameters. [ABSTRACT FROM AUTHOR]

Metal contamination is one of the crucial global problems in aquatic ecosystems that can be hazardous for public health. Due to the living of the benthic fish like large-scale tongue sole (Cynoglossus arel) on the seafloor, toxicants are more accumulated in their bodies. Therefore, the accumulation of some heavy metals (Cd, Cr, Cu, Fe, Ni, Pb, and Zn) was determined in the edible tissues of this fish species captured from Chabahar Bay located in the northern shores of the Gulf of Oman, as well as in the sediment of their environment. For this purpose, thirty fish samples and sediment from five stations were collected during wet and dry seasons. The preparation of samples was done based on standard procedures, and the concentration of metals was measured by a flame atomic absorption spectrophotometer. Besides conventional statistical analysis, Muller's index (Igeo) for the classification of contamination and the biota–sediment accumulation factor (BSAF) were calculated. Results showed that the sediment of Chabahar Bay was classified as moderately contaminated in terms of Ni (Igeo = 1.271) and Pb (Igeo = 1.019). A significant correlation was found between the levels of Ni (18.1 µg∙g−1) in sediments and bio-concentration of Cu (4.85 µg∙g−1), Ni, (0.591 µg∙g−1) and Pb (1.2 µg∙g−1) in fish tissues (p < 0.05). In conclusion, Pb content accumulated in fish or sediment was the most important from the health view. Highlights: The measured Cd and Cu in the sediments of the western cape in winter was significantly higher than in summer (dry season).. A significant correlation was between the levels of Ni in sediments and bio-concentration of Cu, Ni, and Pb in fish tissues. A significant correlation was between the sampling stations and heavy metals in sediments (except Fe and Zn) (p < 0.05). A significant correlation was between the bioaccumulation of Ni in fish tissues and the concentration of Cr in sediments (p < 0.05). [ABSTRACT FROM AUTHOR]

The accumulation of microplastics (MPs) is a growing problem in aquatic ecosystems. Despite increased research on MPs in the last decade, their potential threat to freshwater ecosystems remains an open question. In the present study, the negative impacts of MPs were investigated on blood biochemical parameters in the European pond turtle (Emys orbicularis). Pond turtles were distributed into three experimental groups (n = 9 for each group) and were fed diets containing 250, 500, and 1000 mg MPs (PE100 polyethylene) per kg of food for 30 days, and a control group fed with a standard uncontaminated diet. The results indicated that exposure to 500 and 1000 mg kg−1 MPs caused a significant increase in the activities of alanine and aspartate aminotransferases, and in the levels of cholesterol, glucose, creatinine, urea, and calcium (Ca+2) compared with the control group. On the contrary, the activity of gamma-glutamyl transferase and the levels of total protein, albumin, total immunoglobulins, and phosphorus were significantly reduced in E. orbicularis exposed to 500 and 1000 mg kg−1 MPs when compared with the controls. In all the MP-exposed groups, the activity of lactate dehydrogenase and globulin and magnesium (Mg+2) levels were significantly reduced; while creatine phosphokinase and alkaline phosphatase activities were increased with respect to the control turtles. A significant decrease in triglyceride levels was reported in E. orbicularis exposed to 1000 mg kg−1 MPs. MPs intake induced notable alterations in blood biochemical parameters of E. orbicularis. These results suggest that changes in the blood biochemical parameters could be an appropriate bio-indicator to evidence the existence of tissue damage in E. orbicularis. [ABSTRACT FROM AUTHOR]

Glyphosate is an herbicide that inhibits the growth of weed plants, while chlorpyrifos is an insecticide commonly applied to control the pests' population. This study aimed to investigate the combined effects of chlorpyrifos and glyphosate on biochemical, immunological parameters, and oxidative stress biomarkers in freshwater crayfish Pontastacus leptodactylus for 21 days. The experimental design of this study was factorial (3 × 3), including 0.0, 0.4, and 0.8 mg L−1 glyphosate and 0.0, 2.5, and 5 µg L−1 chlorpyrifos. The exposure to chlorpyrifos, glyphosate alone and a mixture of them significantly decreased acetylcholinesterase, alkaline phosphatase, phenoloxidase activities, and total protein levels. The lactate dehydrogenase, glutamic-pyruvic-transaminase, and catalase activities, the contents of glucose, and malondialdehyde levels were increased in the crayfish. No significant changes were detected in glutamic-oxaloacetic-transaminase (SGOT) activity, triglyceride, and total antioxidant (TAO) levels in the crayfish treated with 0.4 mg L−1 glyphosate and the control group. Co-exposure of crayfish to chlorpyrifos and glyphosate increased SGOT activity and TAO levels. Although chlorpyrifos combined with glyphosate decreased the γ-Glutamyltransferase (GGT) activity, the GGT activity was significantly increased in the P. leptodactylus exposed during 21 days to 5 µg L−1 chlorpyrifos alone and 0.8 mg L−1 glyphosate alone. In comparison with the reference group, no significant changes were evidenced in the cholesterol levels in the P. leptodactylus treated with 2.5 µg L−1 chlorpyrifos, but its levels were significantly increased in the other treatment groups. In conclusion, the mix of glyphosate and chlorpyrifos exhibited synergic effects on the different toxicological biomarkers in the narrow-clawed crayfish. Co-exposure to pesticides may result in disruption of homeostasis in the crayfish by altering the biochemical and immunological parameters. [ABSTRACT FROM AUTHOR]

So far, there have been no studies on the distribution of viral white spot syndrome in wild Indian white shrimp (Fenneropenaeus indicus) brooders at Iranian capture sites. This study was conducted to investigate the presence of white spot syndrome virus (WSSV) in wild Indian white shrimps in Iran, using PCR, histopathologic, and electron microscopic surveys. The samples were collected within two seasons (autumn and spring) and from two provinces (six capture sites), from the major hatcheries providing spawners. Eight hundred thirty-three samples were collected and analyzed first by PCR, after which the positive samples were examined using histological tests, and if inclusion bodies were observed, electron microscopy was also used. White spot syndrome virus was detected only at the capture sites in Sistan and Baluchistan Province, where the mean infection rate was significantly higher in the spring (8.7%) than in the autumn (2.03%). At the Chabahar, Pasabandar, and Govater capture sites, the mean infection rate was significantly higher (4.9%, 2.1%, and 9.2%, respectively), than in Hormozgan Province. The results showed that there was no significant difference in infection rate between the two different sizes and sexes of shrimps (P < 0.05). Phylogeny analysis revealed a close relationship between the viruses from this study and those in other Asian countries, including China, India, Bangladesh, Thailand, Taiwan, and South Korea. It is possible that the virus has spread across the Indian Ocean to other countries. Therefore, the spawners in this study, particularly those collected during the spring and those from capture sites in Sistan and Baluchistan Province, were found to be more susceptible to WSSV infection, and the virus might have been transmitted vertically from WSSV-infected brooders to post-larvae. [ABSTRACT FROM AUTHOR]

One of the narrow-clawed crayfish of the freshwater is named Astacus leptodactylus. As the only crayfish species native to Iranian waters, Astacus leptodactylus is commonly distributed in Iranian water resources. Crayfish is considered a suitable biological indicator of the quality of water, a measure for the assessment of ecology and toxicology (ecotoxicology), and a model organism for the determination of the impact of pollutants. Blood biochemical parameters are useful indicators used to assess the physiological conditions of aquatic animals' response to stress, contamination, physiological, and ecological changes; for this to work, knowing the normal parameter levels is vital. This study was aimed to determine the normal interval of the biochemical parameters in these species in Iran, which appears to be necessary for future planning and studies, especially for ecotoxicological studies. Biochemical parameters analyzed in this study were glucose (11.37 ± 1.53 mg/dl), urea (5.58 ± 0.62 mg/dl), creatinine (0.21 ± 0.02 mg/dl), AST (7.54 ± 0.82 U/L), ALT (7.04 ± 0.97 U/L), ALP (380.44 ± 33.46 U/L), total bilirubin (0.45 ± 0.32 mg/dl), calcium (8.39 ± 1.15 mg/dl), phosphorus (2.35 ± 0.24 mg/dl), total protein (1.72 ± 0.16 g/dl), albumin (4.30 ± 0.2 g/dl), iron (128.79 ± 12.54micg/dl), and magnesium (1.84 ± 0.32 mg/dl). The total number of hemocyte in samples was calculated to be mean 5.3 × 104 per milliliter (n = 30, range 3.9 × 103–1.59 × 105). [ABSTRACT FROM AUTHOR]

Very little is known about parasitic diseases of European pond turtles ( Emys orbicularis) in Iran. The objective of this study is to examine parasitic fauna of European pond turtles collected from Fars province, southwest Iran. Carcasses of turtles (n = 52) which died during dredging procedure are collected from earthen fishery basins in Zarghan region. They have been died earlier during dredging procedure in different farms. Three species of helminths in total were found in gastrointestinal tract, including two nematodes ( Serpinema microcephalus and Falcaustra araxiana) and one digenean trematod ( Telorchis assula). Large intestines of all examined turtles were infected by F. araxiana (100 %, Mean intensity = 18) and this nematode were also found in gastric nodules. Nine turtles (17.3 %, 3 male, 6 female, Mean intensity = 3) were infected with Serpinema microcephalus. T. assula were found in 25 turtles (48.07 %, 5 male, 20 female, mean intensity = 5). Helminths were not found in any examined organs and no ectoparasite found eighter. F. araxiana is the most prevalent nematode in European pond turtles. Detection of Serpinema.microcephalus is in agreement with the fact which this parasite is common parasite of turtles in all over the world. T. assula might be transmitted between variety of reptiles so presence of the trematod should be considered as a risk factor for other reptiles. [ABSTRACT FROM AUTHOR]