[Evaluation of mineral nutrition of milk cows in the period between pregnancies (study of a herd with reduced fertility)].

Studies were carried out on the evaluation of the condition of minerals in cows of a herd with reduced fertility, including 7 head of primiparae and 7 head of multiparae, in the period of interpregnancy. On the basis of analyses of fodder, blood serum and hair mineral disproportions were found which were manifested by excess calcium and deficiency of copper and phosphorus in the organism of the cows. This could be the reason of decreased fertility indices of the herd studied.