Comparing the effect of oral supplementation of vitamin E, injective vitamin E and selenium or both during late pregnancy on production and reproductive performance and immune function of dairy cows and calves

比较妊娠后期口服补充维生素E、注射补充维生素E和硒或两者联合补充对奶牛和犊牛生产性能、繁殖性能和免疫功能的影响