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The aim of this study was to assess the effects of vegetable oils on the antioxidant capacity, blood lipid components and immune responses in chickens raised in hot climate. In a completely randomized design, 300 chicks were assigned to four treatments and five replicates with 15 chicks per each. The highest concentration of malondialdehyde was found in broilers fed palm oil (p < 0.05). Chickens fed corn oil had the lowest and those fed flaxseed oil had the highest antioxidant enzymes activities (p < 0.05). The highest hepatic Alanine-transferase and Aspartate-transferase was found in chickens fed corn oil and the lowest levels in those received flaxseed and olive oils (p < 0.05). The highest hypersensitivity was in chickens fed palm oil and the lowest was for olive oil. The highest antibody titer against sheep red blood cells was found in chickens fed flaxseed oil and the lowest titer was for those received palm oil (p < 0.05). The highest triglyceride, cholesterol and very low density lipoprotein and the lowest high density lipoprotein was found in chickens fed palm oil and vice versa for flaxseed and olive oils. Olive and flaxseed oils had beneficial effects on antioxidant activity and lipid attributes and palm oil had detrimental effects on these parameters that related to the poultry health.

This study was designed to examine the protective effects of nano-selenium and nano-zinc oxide on queen and workers performance under heat stress condition and gene expression of heat shock protein 70 (hsp70) as an index of heat tolerance. Sixty colonies were randomly assigned to five treatments with 12 replicates from June until early September. Sugar syrup (50%) containing no supplement or nano-selenium at levels of 50 and 100 µg L-1 or nano-zinc at levels of 100 and 200 µg L-1 was fed to colonies. Nano-selenium supplementations had no effect, but nano-zinc at level of 100 µg L-1 significantly decreased body malondialdehyde concentration. The highest bee population was seen in nano-zinc at level of 100 µg L-1 and the lowest one in control group. The lowest and the highest body weight, fat and protein deposition was found in group received nano-zinc at level of 100 µg L-1 and control, respectively. The highest gene expression was for group received nano-zinc at level of 100 µg L-1 In group received nano-zinc at level of 100 µg L-1, an increase in hsp70 gene expression was found. In conclusion, nano-zinc oxide at level of 100 µg L-1 could increase queen and worker performance and heat resistance of bees in the hot climate condition.

The objective of this study was to assess the effects of auto-lysed yeast and yeast extract on performance and immune responses of cows in hot climate in the early lactation period. Twenty five lactating dairy cows randomly assigned to 5 groups and 5 replicates. Cows received basal diet with or without auto-lysed yeast (20 or 40 g/d/head) or yeast extract (20 or 40 g/d/head) as on top-dressed. There were no differences for daily dry matter intake, milk production milk fat and the counts of red blood cells and white blood cells among treatments (p > 0.05). There were significant differences among treatments for immunoglobulin G (IgG) level, lymphocyte and neutrophil percentages. Yeast extract had no effect on IgG level, but auto-lysed yeast increased IgG level and neutrophil percentage and decreased lymphocyte percentage (p < 0.05). The highest relative interleukin-2 gene expression was for cows received auto-lysed yeast at the level of 40 g/d/head. Yeast extract had no significant effect on interleukin-2 gene expression as compared to the control group. It was concluded that auto-lysed yeast at the level of 40 g/d/head had no effect on performance, but it could positively influence on immune response of lactating dairy cows in hot climate during early period of lactation.

This experiment was conducted to evaluate the effects of in ovo injection of nano-selenium (Nano-Se) and nano-zinc oxide (Nano-ZnO) and high eggshell temperature (EST) during late incubation on blood parameters of broiler hatchlings. A total of 750 fertile eggs, were weighed and randomly distributed among 5 treatment groups on each of 5 replicate tray levels. The injection was performed on 17 d of incubation. Treatments included of: 1) Eggs not injected and incubated at normal EST (control); 2) Eggs not injected and incubated at high EST; 3) Eggs injected NaCl solution and incubated at high EST (sham); 4) Eggs injected NaCl solution containing 40 µg Nano-Se and incubated at high EST; 5) Eggs injected NaCl solution containing 500 µg Nano-ZnO and incubated at high EST. EST of 37.8ºC (normal) or 38.9ºC (high) was applied from d 19 to 21 of incubation. In ovo injection of Nano-Se and Nano-ZnO significantly increased activity of GSH-Px and SOD and total protein, but decreased the levels of corticosterone, cortisol, T4 and T3 at high EST. Injection of Nano-Se and Nano-ZnO had a significant role in alleviating the negative effects of high temperature incubation and heat stress by increased antioxidant activity and reduced oxidative stress.

The aim of the present study was to compare the effects of unsaturated and saturated oils on the performance, hormonal levels and hsp gene expression in broiler chickens exposed to heat stress. 300 one-day male broiler chicks were assigned to 4 treatments (Diets containing palm, corn, linseed or olive oils) with 5 replicates. At day 28 of age, 2 chickens were removed from each replicate, then blood samples and liver tissue samples were collected for analyses. Feeding linseed and olive oil reduced feed conversion ratio compared to corn and palm oils. The lowest level of insulin was for chickens fed linseed oil and corn oil. The highest level of corticosterone was found in chickens fed palm oil and the lowest level was for those received linseed oil. Chickens received linseed and corn oils had the highest levels of T3 and T4 and those fed palm and olive oils had the lowest levels. The highest HSP 70 gene expression was for chickens fed diet containing olive and linseed oils and the lowest one was for those fed corn and palm oils. It was concluded that olive oil and linseed oil could improve performance and heat tolerance of chickens under heat stress.

The aim of this study was to determine the effects of supplementing close-up and fresh dairy cows’ diets with sodium selenite or organic sources of selenium (Se) on the serum biochemical parameters and antioxidant indicators and Se status. Twenty-four multiparous Holstein dairy cows were balanced by body condition score (BCS), previous lactation milk yield and expected calving date and randomly assigned to 1 of 4 experimental treatments. Treatments were: control (basal diet without Se supplementation), sodium selenite supplementation (0.50 mg of Se kg-1 DM; Se-S), selenium yeast supplementation (0.50 mg of Se kg-1 DM; Se-Y) and selenomethionine supplementation (0.50 mg of Se kg-1 DM; Se-M). Serum Se concentrations were higher for cows in Se-Y (72.34 µg dL-1) and Se-Met (72.34 µg dL-1) than control (59.93µg/dl) and Se-S (64.79µg/dl). The Se supplementation and sources did not affect serum metabolites or indices of antioxidant pre and postpartum, except serum total protein and albumin concentrations. Cows in Se-M had greater serum total protein and albumin concentrations than those in control. The results of present study showed that serum Se concentrations increased in Se-Y and Se–M more effectively than Se-S, indicating that selenomethionine could replace Se-S as an effective organic Se source for transition dairy cows.

In the present experiment, 320 one day old Ross 308 broiler chickens were used completely randomized design with 4 treatments, 4 replicates, and each replicate contained 20 broiler chickens. Experimental treatments include control, 0.5, 1, and 2% of Thymolina powder in chickens’ diet. Thymolina® is an anti-bacterial powder drug which is made by composing 4 medicinal plants. A significant difference observed between treatments in each parameter of the Intestinal morphology (villus height, villus width, crypt depth and epithelial thickness). Goblet cells number was not affected. Our findings indicated that using Thymolina® in the diet of broiler chickens causes improvements in carcass characteristics. Therefore, it may improve the carcass characteristics and morphology of small intestine in broiler chickens.