Veterinary Research Forum

Abstract Nutritional interventions play a pivotal role in sustaining egg production performance and improving egg quality parameters in aged laying hens. The present study was conducted to investigate the effect of L-carnitine (LC) supplementation in diets containing different levels of fish oil (FO) on performance, egg quality parameters and egg yolk fatty acids (FAs) profile in aged laying hens. In this study, 432 laying hens (Hy-line-W36, 65 weeks of age) were used and allocated in a 3 × 3 factorial design with six replications and eight birds per replication. The experimental treatments included diets containing three levels of FO (0.00, 1.50 and 3.00% of the diet) and three levels of LC (0.00, 300, and 600 mg kg^-1 of the diet). The results showed that hens treated with 3.00% FO and 300 and 600 mg LC had the highest egg production rate, egg weight and egg mass which was significantly higher than the treatments without FO and LC. With increasing usage level of FO to 3.00% of diet, egg yolk pH was significantly decreased, however, yolk pH was increased when diet was supplemented with 600 mg LC. The percentage of polyunsaturated FAs, the ratio of polyunsaturated FA/saturated FAs and the percentage of omega-3 FAs were increased significantly with increasing FO usage level in the diet. Overall, these findings suggested that dietary supplementation with FO and LC could synergistically improve productive performance and enhance the nutritional value of eggs in aged laying hens.

Abstract The effects of garlic oil (GO) on serum fatty acids, lipid profiles and energy-related blood metabolites in feed-restricted fat-tailed ewes were investigated. For this purpose, twenty-eight dry, non-pregnant Makuei ewes (about three years of age; 45.00 ± 2.20 kg of body weight) were assigned randomly to four experimental groups including group 1 receiving basal diet as total mixed ration (TMR) without GO supplementation (control group), group 2 receiving 100% basal diet supplemented with GO (10.00 mg kg^-1 BW), group 3 receiving 70.00% basal diet without GO supplementation and group 4 receiving 70.00% basal diet supplemented with GO (10.00 mg kg^-1 BW). The main experimental period started eight weeks after performing adaptation and dietary allocations. Feed restriction reduced serum glucose levels along with higher serum levels of non-esterified fatty acids, triacylglycerols, β-hydroxybutyrate, low-density lipoprotein cholesterol, total cholesterol and very low-density of lipoprotein. Following feed restriction, the serum palmitic and oleic acids concentrations were increased. Garlic oil supplementation had a desirable effect on feed-restricted animals through lowering serum BHB and palmitic and oleic acids concentration and increasing the high-density lipoprotein cholesterol levels in the serum. These findings demonstrated that GO had the potential to reduce body-fat mobilization, thereby lowering the risk factors for disorders associated with negative energy balance in underfed ewes in the periparturient period.