Effect of dietary fat on the content of vitamins and carotenoids in egg yolks

Abstract

Abstract This study evaluated the effects of fat source in the diet on the content of vitamins E and A, and carotenoids in egg yolks. Hisex Brown hens aged 49–56 weeks were fed on diets that differed in the content of crude fat (a diet without fat and diets supplemented with rapeseed or palm oil at 40Â g/kg). Diets of all hens contained 3% dehydrated alfalfa (a source of carotenoids). Measurement of vitamin and carotenoid content in yolks was carried out by HPLC methods. Supplements of fat increased the α-tocopherol content in egg yolks by 80.1% (rapeseed oil) and 72.1% (palm oil), respectively. The increase of lutein, zeaxanthin and retinol in yolks of hens fed dehydrated alfalfa and oils was less pronounced (varied from 13.4% to 26.5%). Effects of dietary fat supplementation on deposition of lipophilic vitamins and carotenoids were small or statistically non-significant. The saturation of diets with fat increased the hen-day egg production and decreased the feed intake. It can be concluded that dietary inclusion of fat increased the deposition of α-tocopherol, retinol and carotenoids in eggs of hens fed a diet containing dehydrated alfalfa.