Effects of different selenium source supplementation on performance, EGG selenium concentration, fatty acid composition and lipid oxidation prameters in laying hens fed on diets containing sunflower oil

This study was conducted, in order to determine the effects of adding sunflower oil, inorganic or organic selenium to rations of laying hens on performance and egg quality criteria, egg fatty acid profile, egg selenium concentration and lipid oxidation parameters. In the experiment, 252 Lohmann LSL-Classic white laying hens at 42 weeks of age were used. The chickens were randomly distributed to 6 groups to be 7 replications in each treatment group and 6 animals per replication (6x7x6). The rations used in the 12-week trial were prepared in two different ways as isonitrogenic and isokaloric, sunflower oil and oil-free. Organic and inorgnic selenium additives were added to both oil-free and oily rations at the amount of selenium to be 0.3 mg / kg in total ration. The effects and interactions of treatments, on egg quality criteria such as egg weight, shape index, shell ratio, shell thickness, color scale, egg albumen index and egg yolk index, were determined as important. The concentration of selenium in eggs in selenium added groups was found to be higher than those without selenium (p˂0.05). Egg selenium concentration was higher in the groups added to organic selenium than in the groups added with inorganic selenium (p<0.05). The effect of addition of fat to the yolk fatty acid composition was found as significant (p˂0.01). Fatty ration-fed groups, especially egg yolk polyunsaturated fatty acids, were found to be higher values than the groups fed with oil-free rations (p˂0.05). In the groups fed with oily rations, the egg malondialdehyde (MDA) concentration (TBARS, thiobarbituric acid reactive substances) were found to be higher than the groups fed with oil-free rations (p˂0.05) and it was determined, the addition of selenium decreased the egg TBARS value in groups fed with oily rations (p˂0.05). The effects and interactions of the treatments on blood parameters (Catalase (CAT), Superoxide dismutase (SOD), Glutathione peroxidase (GSH-Px) and MDA) were also found to be statistically significant (p˂0.01). As a result; It was observed that the addition of sunflower oil to the laying hens rations did not affect performance and egg quality criteria, but increased the amount of linoleic acid in n-6 fatty acids in the egg and egg weight. The addition of both selenium to the oily and oil-free rations, in particular the addition of organic selenium, has been shown to increase the egg Se concentration and have a positive effect on egg shelf life.