BACKGROUND: Omega-3 fatty acids can be conducive toreducing the harmful effects of physiological stress through reducing the stimulatory activity of glutamatergic neurons.OBJECTIVES: The aim of this study was to investigate the effects of omega-3 fatty acids on performance, blood parameters, and the profile of fatty acids in the egg yolks of laying hen under stress.METHODS: This study was performed using 96 LSL-Lite laying hens in a 2 × 3 factorial experiment with 2 factors, namely stress (no dexamethasone and 1.5 mg/kg of diet dexamethasone) and omega-3 fatty acids (the levels of 0, 0.24 and 0.48 % of diet), in a completely randomized design for 70 days from 35 to 44 weeks of age.RESULTS: Physiological stress reduced the feed intake, the percentage of egg production, and egg mass in laying hens (P<0.05). Omega-3 fatty acid supplements had no effects on these traits. The groups receiving 0.48 % of omega-3 fatty acids had the lowest heterophil:lymphocytes (P<0.05), and there was no difference between stressed and non-stressed groups. The ratio of omega-6 to omega-3 fatty acids was higher in birds previously affected by stress (P<0.05). Feeding with omega-3 fatty acids in birds increased omega-3 fatty acids in egg yolk and reduced the ratio of omega-6 fatty acids to omega-3 in laying hens (P<0.05).CONCLUSIONS: Based on the results of this experiment, physiological stress had a negative effect on performance traits, and the use of omega-3 fatty acids in laying hens under stress had no effect on performance traits. Physiological stress altered the profile of fatty acids and increased the proportion of omega-6 to omega-3 fatty acids in egg yolk. The use of omega-3 fatty acids reduced the negative effects of stress and improved the profile of fatty acids in egg yolk.

BACKGROUND: Optimal levels of minerals in the diet are crucial for improving performance and immune response against the environmental stresses.OBJECTIVES: This study was conducted to evaluate the effects of water supplementation of chelated trace mineral (CTM) on growth performance, hematology, blood biochemistry, antioxidant status, and antibody response in broilers reared under heat stress condition.METHODS: A total of 240 male Ross 308 broiler chickens were randomly allocated into one of the following five treatments (each consisting of four replicates): (1) positive control (PC; thermoneutral condition), (2) negative control (NC; heat stress condition), (3) low-CTM (NC + low CTM level in tap water), (4) medium-CTM (NC + medium CTM level in tap water),  and (4) high-CTM (NC + high CTM level in tap water). The CTM levels in the tap water for the low-CTM treatment were 0.1, 0.15, 0.3, 0.4, and 0.45 mg/bird/day on days 1-10, 11-20, 21-30, 31-40, and 41-50, respectively. The respective values were 1.0, 1.5, 3.0, 4.0, and 4.5 for the medium-CTM, and 10, 15, 30, 40, and 45 mg/bird/day for the high-CTM water.RESULTS: The average weight gain during the whole experimental period in the medium-CTM treatment was higher compared to that in the negative control treatment, but lower than that in the positive control treatment (P<0.05). The heterophil/lymphocyte ratio and total antibody titers against Newcastle disease in the medium-CTM and high-CTM groups were similar to those of the broilers in the PC group, yet better (P<0.05) those of the NC group. The serum superoxide dismutase activity was also higher (P<0.05) in the high-CTM group compared to that of the NC group.CONCLUSIONS: The results suggested that the water supplementation of CTM at a moderate level (1.0, 1.5, 3.0, 4.0, and 4.5 mg/bird/day during different rearing periods) could be a strategy to ameliorate the detrimental effects of heat stress in broilers.

BACKGROUND: Open wounds affecting the distal part of limbs are commonly seen in horses. Due to certain factors, such as limited connective tissue available, potentiated growth of excessive granulation tissue, risk of contamination, and poor response to common treatments, healing of these wounds becomes a major problem for veterinarians on a number of occasions. Application of Mesenchymal Stem Cells (MSC) for enhancing wound healing has received a great deal of scientific attention. Among the MSCs, those derived from adipose tissue are frequently used owing to their availability, large number of cells after the primary harvest, and the capacity to differentiate to different cell lines.OBJECTIVES: The current study aimed to evaluate type 1 and 3 collagen genes expression in horse distal limb wounds treated via adipose-derived Mesenchymal Stem Cells and its comparison with bone marrow-derived stem cells.METHODS: After treatment of the experimental open wounds created in the distal limbs of four horses via autologous MSCs, real-time PCR was used for evaluating and comparing the expression of type I and III collagen genes in the healing wounds.RESULTS: Significant differences in the expression of type I and III collagen genes were observed between the treatment groups. Despite the fact that the greatest collagen genes expression belonged to bone marrow-derived MSCs, no significant differences were seen with adipose-derived MSCs.CONCLUSIONS: Owing to the advantages and an acceptable performance, adipose-derived MSCs could be considered as a novel approach to enhancing limb wound healing in horses.

BACKGROUND: During the modification of several races, which has been done on chickens, there have been several changes in the function of neural pathways and receptor density involved in the control of food intake and appetite. Melanocortin system and its receptors are involved in the central regulation of nutritional behaviour and energy balance. Therefore, this study was designed to investigate the role of this system in the central control of food and water intake in birds.OBJECTIVES: The present study aimed to evaluate the role of MCR3 and MCR4 receptors in controlling the food and water intake in birds.METHODS: This work was performed on 48 Ross 308 broiler chicks through two experiments (each experiment in four groups). Primarily, stereotaxic surgical guide cannula was implanted in the chickens. Subsequently, in the first experiment, the chickens were divided into the four following groups: the control solution, 0.2, 2, and 10 nmol/5µl of SHU9119 (Non-selective antagonist of MCR3 and MCR4 receptors) In the second experiment, the chickens were also divided in four groups: the received control solution, 0.2, 2, and 10 nmol/5µl of MCL0020 (Selective MCR4 receptor antagonist) via intracerebroventricular (ICV) injection. Afterwards, cumulative food and water intake were measured at 30, 60, 90, 120, 150, and 180 minutes after the injection.RESULTS: The results of this study showed that ICV injection of SHU9119 and MCL0020 increased cumulative food intake (P>0.05), but did not affect cumulative water intake (P<0.05).CONCLUSIONS: According to the findings herein, central melanocortin system is one of the systems involved in central control of food intake in birds.

BACKGROUND: Tilapia, Oreochromis niloticus, is an omnivorous and important breeding species in the world. Over the recent years, tilapia breeding has begun in Iran. In aquaculture, it is very important to regulate a balanced diet in terms of nutrients needed for growth, which would be also economically appropriate.OBJECTIVES: The main objective of this study was to investigate the effect of substituting chicken waste powder in the diet of fish at levels of 0, 25, 50, 75, and 100 % on the tissue structure of different parts of the intestine of Nile tilapia.METHODS: 75 fish (three frequency per treatment) were fed with chicken waste powder instead of fish meal in their diet for eight weeks at 0, 25, 50, 75, and 100 % levels. At the end of the treatment, separate samples were taken from the initial, middle, and end parts of the intestine. After passing the usual histological steps, the slides were assessed by hematoxylin-eosin staining and TUNEL immunohistochemistry technique.RESULTS: In histometric studies, the highest villi height, thickness, muscle layer, and number of goblet cells were reported in the control group and the lowest in the 100 % group. In immunohistochemical studies, the number of apoptotic cells in groups 75 and 100 % was higher than that in the other groups.CONCLUSIONS: According to the results of the present study, it could be suggested that the replacement of chicken waste powder instead of a fish meal up to 50 % for indigo tilapia is tolerable. However, higher levels of chicken waste powder will reduce absorption, and acceptance of food and have adverse effects on growth.

BACKGROUND: Application of different source of minerals and their effect on metabolic performance a current issue in animal science and research centers. OBJECTIVES: The objective of this study was synthesis of selenium nanoparticles and to investigate its effect compared with other selenium sources on the blood parameters associated with the liver functional index of Holstein dairy cow. METHODS: This study was conducted in two phases: laboratory and farm. Oxidation-reduction chemical reactions were used to synthesize selenium nanoparticles. The formation and non-change of Se nanoparticles size were confirmed by particle size analyzer. In order to perform farm experiment, 6 dairy cows were allocated into three treatments and 2 replicates in a 3×3 Latin square experiment with 28 days change over the period. The animals were distributed to three treatment groups. Treatments (diets) were 1) control (sodium selenite source), 2) colloid sodium selenite and 3) selenium nanoparticles. Blood parameters associated with the liver functional index, including albumin, bilirubin and total cholesterol were measured in the present experiment. Also, dry matter intake of cows was recorded. RESULTS: The blood plasma cholesterol of cows fed the colloidal sodium selenite was higher than cows fed the selenium nanoparticles (P-Value =0.01). The blood serum albumin (P-Value =0.03) and bilirubin levels (P-Value =0.04) were lower in group 3 compared with group 1. Dry matter intake was not affected by treatments. CONCLUSIONS: According to the results of this experiment it seems selenium nanoparticles supplementation   improves blood parameters associated with the liver functional index, which can better improve immune system of dairy cows than two other sources of selenium.

BACKGROUND: Staphylococcus aureus is one of the most important human pathogens that cause infection and also food intoxication by secreting various enterotoxins. Conventional culturing methods to detect S. aureus have some limitations such as being time-consuming due to bacterial growth and low precision and sensitivity in detecting viable but non-cultivable cells. OBJECTIVES: The objective of this study was to detect and quantify enterotoxigenic (A-E) S. aureus in cream pastry products applying PCR coupling with propidium monoazide (PMA) to distinguish dead and live cells. METHODS: One hundred samples were randomly collected from pastry shops in Amol, in a period of 2 months. After preparing dilutions, bacterial pellets were separated and treated with PMA before DNA extraction. Real time PCR was conducted in order to quantify S.aureus cells and enterotoxigenic strains using specific primers. RESULTS: Results of conventional method were close to PMA-qPCR data (P>0.05), but data from qPCR that includes live and dead cells shows more bacterial count than two other methods. Sensitivity of the method applied in the present study, detecting low number of S.aureus cells (less than 10/g) seems considerable. CONCLUSIONS: Findings showed that applying PCR coupling with PMA results in more reliable data than conventional culturing method. Regarding this approach being time-effective, considerably sensitive and specific, it is expected that it be used in food quality control labs in monitoring systems in future.

BACKGROUND: Titanium dioxide nanoparticles (TiO2NPs) are used in many commercial products, including paints, sunscreens and edible products, and can be used directly and indirectly in aquaculture. Due to the widespread application of these nanoparticles, the investigation of their possible effects on aquatic organisms is necessary. OBJECTIVES: The purpose of this study was to investigate the histopathological effects of waterborne TiO2NPs on the gills, liver and intestine of Caspian trout. METHODS: In this study, 126 fish (27.46±4.3 g) were tested in six concentrations of TiO2NPs (0, 0.01, 0.1, 1, 10 and 100 mg/L) for 4 days. At the end of the experiment, tissues were evaluated to determine the effects of tissue damage caused by TiO2NPs. RESULTS: The 96-h exposure to TiO2NPs did not cause fish mortality. Accordingly, investigated TiO2NPs are classified as "relatively non-toxic". The most important tissue changes caused by short-term exposure to TiO2NPs were hyperplasia and hypertrophy, lamellar fusion, necrosis in gills; foci of melanomacrophage deposits, aggregation of blood cell, hepatocytes with pycnotic nuclei, vacuolation, necrosis in liver; thickening of lamina propria, erosion of villi and necrosis in intestine. CONCLUSIONS: Although TiO2NPs are relatively non-toxic,  due to the tissue damage observed, these nanoparticles can be harmful to Caspian trout.

BACKGROUND: Diarrhea syndrome is associated with irrecoverable damages in the husbandry industry worldwide due to losses resulted from fatality, weight loss, growing weak calves and treatment costs. Hence, investigation of diarrhea causes in different areas is important to attempt management strategies to prevent and control it. OBJECTIVES: Present study was carried to investigate prevalence of some important entropathogens in diarrheic calves until three months old, in Shahrekord suburb husbandries. METHODS: Fecal samples were taken from 82 female calves in first day of diarrhea and were examined for isolation of salmonella, Escherichia coli, clostridium, cryptosporidium, and coccidia through common microbiological and parasitological methods. RESULTS: In general, prevalence of isolated organisms were: salmonella 36.6%, Escherichia coli 24.4%, clostridium 9.8%, cryptosporidium 9.8%, and coccidian 7.31%, and Escherichia coli K99 were isolated from four calves. The most prevalent pathogens were Escherichia coli and Salmonella. CONCLUSIONS: The calves are unavoidably exposed to infectious causes of diarrhea during their whole lifespan, because they acquire organisms from environment immediately after birth. Therefore, attempts at efficient management methods, hygienic principles and receiving enough colostrum, particularly in cold seasons, may be efficient in the control, prevention and decrease of diarrhea and its subsequent losses.

BACKGROUND: Flufenamic acid is a member of the fenamates and is used as an analgesic and NSAID drug. According to the ability of this drug on blocking connexin and preventing leakage of substances such as ATP from cells, it seems to be beneficial in healing diabetic wounds. OBJECTIVES: Evaluation of the effects of topical flufenamic acid as a connexin-channel blocker on skin wound healing in alloxan-induced diabetic rats. METHODS: In this study diabetics was induced in 40 male rats by IP injection of 150mg/kg of alloxan and they were divided to 4 groups. After anesthesia, 2×2 cm incision was made on the back of the rats and the skin was separated completely. Three groups were treated by 2, 5 and 10 percent concentration of flufenamic acid ointment separately, and one group was treated by Vaseline and ucerine ointment as control. Bandage and ointment were changed daily and the procedure was carried out for 21 days. The wound surface was measured on odd days. Half of the rats of each group on day five and half of them on day 21 were euthanized to get pathologic slides. RESULTS: Process of healing, fibroblast concentration, epithelialization, angiogenesis, collagen formation and wound closure in 2 percent group were better than other groups and in control, 5 and 10 percent groups had a decreasing trend respectively and had a significant difference. In the last two groups, the healing process was disrupted. CONCLUSIONS: The 2 percent concentration of drug not only did not show potent anti-inflammatory effects, but also improved the process of healing by blocking the connexin 43 and inhibition of ATP release, while in the concentration of 5 and 10 percent, anti-inflammatory effects of the drug predominated and delayed the healing process.