The Effect of Boron (Orthoboric Acid) Supplementation into Diets of Laying Hens on Some Egg Yolk Parameters During Late Laying Period

This study was carried out to determine the effects of boron (orthoboric acid) addition into the diets of hens in the late laying period on some egg yolk parameters. Two hundred eighty eight Lohman commercial laying hens which are 62 weeks old were fed with 0, 50, 75, and 150 mg/kg of B for 12 weeks. The research was carried out in 18 replicates, and four laying hens were used for each replicate. During the research, 16-hour lighting was applied, and feed and water were given as ad-libitum. The rates of egg yolk, polar lipid, hydrocarbon+ cholesterol ester and the fatty acid ratios from lipid components were not affected from treatment. While the ratio of triacylglycerol in total lipid is decreased; total cholesterol, diacylglycerol ratios and egg yolk lipid peroxidation levels increased. Boron (B) addition into diets of laying hens affected the outcome of egg yolk protein profile, the proteins being at different molecular weights at different levels. In conclusion, the lipid composition and protein profile of egg yolk and lipid peroxidation parameters were affected by B addition into diets of laying hens. But, further studies are needed to clarify the changes related to the effects of diets including Bor at different levels on some egg yolk parameters of laying hens during late laying period.