The objective of the present study was to research the effect of feeding laying hens fish oil-supplemented diets to produce n-3-enriched eggs on their ovarian follicular development, serum lipid peroxidation, antioxidative status and immune response. A total of 105 white Bovens hens at 24 weeks of age were housed in cages in an open-sided building under a 16 h light : 8 h dark lighting schedule. Birds were randomly divided into five treatments and were fed, ad libitum, diets containing 0% (control), 1.25%, 2.5%, 3.5% or 5.0% fish oil from 24 to 36 weeks of age. Egg production and weight were recorded. By weeks 35 and 36 of age 15 eggs were taken at random from each treatment to determine the yolk lipid profile and cholesterol content. At the end of the experimental period, 10 females from each treatment were randomly chosen, anaesthetised and killed by decapitation. Ovary and oviduct samples were immediately weighted and ovarian follicles were classified. Serum thiobarbituric acid-reactive substance (TBARS), hepatic TBARS and hepatic glutathione peroxidase (GSH-Px) activity were measured. No clear trend was observed concerning egg production and egg yolk cholesterol. As dietary fish oil levels increased, n-3-polyunsaturated fatty acids (n-3 PUFA) increased, whereas n-6 PUFA tended to decrease in yolk lipids. No negative effects were detected in ovary and oviduct weights, expressed in both absolute terms and relative to body weight. The numbers and total weights of large yellow follicles (LYF) in the ovary were not significantly affected by fish oil supplementation. Low levels (1.25% to 2.5%) of fish oil reduced both plasma and hepatic TBARS and enhanced GSH-Px activity. It is also interesting to note that inclusion of 2.5% fish oil in laying hen diets enhanced the antibody titre in laying hens. Therefore, it could be concluded that inclusion of fish oil in laying hen diets at moderate levels increased the n-3 fatty acids content in eggs, improved antioxidative status, enhanced the antibody response and did not have a negative influence on the different reproductive morphology parameters in laying hens.

1. We examined the effects of supplemental dietary vitamin E (Vit E) on semen quality and antioxidative status in male domestic fowls exposed to oxidative stress induced by synthetic glucocorticoid, dexamethasone (DEX) injection. 2. Thirty-six Egyptian local cross males, 42 weeks old, were housed individually in cages in an open-sided building under 16 h light:8 h dark and were provided with commercial feed and water ad libitum. Birds were divided into 4 groups: DEX (4 mg/bird/d), Vit E (200 mg/kg diet), DEX + Vit E (4 mg/bird/d + 200 mg/kg diet, respectively) and control, n = 9. All treatments lasted for 7 continuous days. 3. Oxidative stress induced by injection of DEX (4 mg/bird/d) resulted in decreased sperm count and motility correlated with an increased percentage of dead sperms. Vit E (200 mg/kg diet) enhanced sperm count and viability when supplemented to stress-induced birds, compared to DEX treatment alone. 4. In seminal plasma, low calcium concentration, high lipid peroxidation and reduced activity of glutathione peroxidase were associated with the oxidative stress. Vit E reduced lipid peroxidation in the seminal plasma. 5. In conclusion, excessive supplemental dietary Vit E improved semen quality when cockerels were subjected to stress conditions. It increased both sperm count and motility, reduced the percentage of dead sperm and enhanced the antioxidative status of seminal plasma.

1. The effects of dietary polyphenols (PP) on growth and oxidative stress in the corticosterone (CTC) treated broiler chickens model were studied. 2. Chicks (Cobb strain) were divided into 3 (CTC) x 3 (PP) blocks and given diets containing CTC at concentrations of 0, 10 and 20 mg/kg. 3. The body weight gain was lower when the birds were treated with CTC. However, the high dose of PP tended to reduce the effect of CTC. 4. The abdominal fat content, plasma triglyceride concentration and liver weight were increased by CTC and reduced by PP. 5. Muscle and liver thiobarbituric acid reactive substance (TBARS) were elevated by CTC and these effects were reduced by PP. Plasma CTC concentration was increased by dietary CTC treatment and decreased by PP. 6. In conclusion, our results indicate that PP can minimise growth inhibition, hyperlipidemia and oxidative stress induced by CTC treatment in broiler chickens.

The present study was conducted to show that dietary supplementation with a fungus, Aspergillus awamori, modifies muscle fatty acid profiles in broiler chickens. A total of thirty chicks, selected from a group of 100 chicks aged 15 d, were divided into a control group and two treatment groups (ten birds per treatment). The control group was fed a basal diet, and the treatment groups were fed basal diets supplemented with A. awamori at levels of 0·05 and 0·2 %. From the start of the study at 15 d, the birds were raised for an additional 12 d, and growth and the muscle fatty acid profile were evaluated. Although feed intake was decreased by the fungus, body-weight gain and breast muscle weight were increased, and thus, feed efficiency was improved. Abdominal fat and plasma cholesterol and TAG were decreased, while plasma HDL-cholesterol and breast muscle fat content were increased. Interestingly, muscle a-tocopherol content was increased and muscle thiobarbituric acid-reactive substances were decreased by A. awamori. Furthermore, there was an observed decrease in SFA and an increase in unsaturated fatty acids in the muscle fat due to the fungus feeding. The mRNA of fatty acid synthase, acetyl-CoA carboxylase and D-6 desaturase in the muscle were all increased, while the mRNA of 3-hydroxyl-3-methylglutaryl-CoA reductase and carnitine palmitoyl transferase 1A were decreased by the fungus. In conclusion, the present study clearly shows that the muscle lipid profile could be modified by the addition of A. awamori to the diet.

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This study was conducted to show that dietary supplementation of a fungus, Aspergillus awamori called Koji in Japan, reduces skeletal muscle protein breakdown and stimulates growth in broiler chickens. A total of 30 chicks at 15 days of age was divided into control and two treatment groups (10 birds per treatment). Control group was fed basal diet and treatment groups were fed the basal diets supplemented with A. awamori at levels of 0.05% and 0.2%. The birds were raised for 12 days from 15 to 27 days of age and then the effect on growth, organ weights and plasma 3-methylhistidine concentration and digestibilities of protein and energy was evaluated. The messenger RNAs (mRNAs) of atrogin-1, ubiquitin, proteasome, m-calpain, µ-calpain, β-actin, myosin and pax-7 in the breast muscle were also measured. Body weight gain and breast muscle weight were increased, although feed intake was decreased by the fungus and thus feed efficiency was increased. Protein and energy digestibilities were increased. Furthermore, plasma 3-methylhistidine concentration was decreased by the fungus. The mRNAs of atrogin-1, ubiquitin, proteasome, m-calpain and µ-calpain were all decreased. The mRNA of β-actin but not myosin and pax-7 was slightly increased by the fungus. In conclusion, feeding A. awamori improves growth performance because skeletal muscle proteolytic activity is reduced and digestibilities of energy and protein are increased.

The objective of the present study was to research the effects of different supplemented dietary sources of n-3 polyunsaturated fatty acids (n-3 PUFA) to produce n-3 enriched meat on growth performance, meat quality, serum antioxidative status, immune response and tibia bone characteristics in Japanese quail. Three hundred 1-day-old Japanese quail chicks were randomly weighed and divided into five dietary treatments containing 0% oil (C, negative control), 2% vegetable oil (VO, positive control), 2% linseed oil (LO), 2% fish oil (FO) and a mixture of 1% linseed oil +1% fish oil (LO+FO). Body weight and feed consumption were recorded. Fatty acid profile, cholesterol content, chemical composition and physical characteristics of breast meat were determined. Serum thiobarbituric acid-reactive substances (TBARS), glutathione peroxidase (GSH-Px) activity and total antioxidant capacity were measured. No negative effects were detected in live weight, feed consumption and physical characteristics of meat. The incorporation of n-3 PUFA in the meat proved to be successful when different sources of n-3 PUFA were used. The supplementation of n-3 PUFA caused a significant decrease in TBARS values and a significant increase in both the GSH-Px activity and total antioxidant capacity. Interestingly, the inclusion of n-3 PUFA in quail diets enhanced the antibody titre and bone morphological characteristics. Therefore, it can be concluded that the inclusion of n-3 PUFA in diets at moderate levels increased the n-3PUFA content in meat, improved the antioxidative status, reduced lipid peroxidation, enhanced the antibody response and bone morphological characteristics and did not have any negative influence on physical characteristics of meat and growth performance in Japanese quail.

The objective of the present study is to research the effect of dietary vitamin E (Vit E) on laying performance, lipid peroxidation and antioxidative status in laying hens under experimentally induced oxidative stress conditions via Dexamethasone (DEX) administration. A total of 60 Egyptian local strain (Gimmizah) laying hens at 36 weeks of age were housed in individual cages in an open-sided building under a 16 hr light: 8 hr dark lighting schedule. The birds were randomly divided into four experimentally treatments: DEX (4 mg/hen/day); Vit. E (200 mg/kg diet); DEX+Vit. E (4 mg/hen/day+ 200 mg/kg diet respectively); and control (n= 15). The birds were provided with commercial feed and water ad libitum. All treatments lasted for 7 successive days. Oxidative stress induced by DEX injections significantly reduced egg production and egg weight. Vit. E alleviated this reduction when supplemented to the stress-induced hens, compared to DEX treatment. A high level of yolk lipid oxidation was associated with oxidative stress treatment and it was reduced by Vit E supplementation. It could be concluded that supernutritional levels of Vit E (200 mg/kg diet) may contribute in enhancing laying performance and antioxidative status of laying hens under stress conditions.