The vitamin E status of lactating dairy cows after receiving stored feeds for 15 months.
Twelve cows were divided into two equal groups on milk production and fat test to determine if continuous feeding of stored feedstuffs can cause vitamin E deficiency in dairy cattle. One group of cows (high vitamin E) was maintained on a normal summer pasture - winter dry lot feeding schedule. The second group (low vitamin E) was fed stored feeds year-round in a dry lot. At the end of 15 mo, vitamin E in the milk, milk flavor, selenium in blood and milk, blood hemolysis, and the standard Wintrobe blood factors were determined. There were no significant differencesbetween the two groups. Average vitamin E and 5-day oxidized milk flavor scores for the two groups were 3.37 1,tg/g fat and 1.16 for the low E and 3.24 p,gl g fat and 1.11 for the high E. Mean corpuscular volumes were 57.70 (1,tID)3 for low E and 55.84 (1,tID)3 for high E. Mean corpuscular hemoglobin values were 19.04 and 17.74 pg. Blood of one cow in the low vitamin E group hemolyzed whereas the remaining cows were normal.