INFLUENCE OF FEEDING OF OILSEEDS AND BY-P RODUCTS FROM OILSEEDS ON VITAMIN-E CONCENTRATION OF ANIMAL PRODUCTS

In 5 feeding studies dairy cows, beef cattle and pigs were fed diets w ith different contents of oil seeds or oil seed expellers. Thus, the e ffects on vitamin E concentration in animal products were analyzed aga inst a reference diet, which was free from these components. Dairy cow s received 1 kg full fat rapeseed (430 g fat; 31 mg alpha-tocophherol/ kg DM). Beef cattle were fed rations with 7, 14 and 21% rapeseed and p igs were administered concentrates containing 10% rapeseed, 20% full f at soybeans or 5 and 10% false flax expeller. Feeding full fat oilseed s or their expellers resulted in an increased fat and alpha-tocopherol intake. Incorporating full fat rapeseed into the diets induced a sign ificant increase of vitamin E-concentration in milk and other body sam ples. In contrary to this increase expeller feeding caused a decreased vitamin E-concentration in animal products. The fatty acids pattern o f the oilseeds and the expellers have shown a clear influence on the f atty acid pattern of body fat in pigs, followed by milk and finally bo dy fat of ruminants with an insignificant influence only. Fatty acid p attern, disposition for oxidation and vitamin E content of the various fat types influences their induction times. Feeding full fat oilseeds to ruminants, resulted in an increased induction time, in contrast, w hen fed to pigs the induction time decreased. Feeding expellers, the i nduction times of the Various fat samples of both species decreased, d ue to the expected destruction of vitamin E.