The effect of two mineral-vitamin premixes on the blood biochemical parameters, milk yield and composition of Holstein-Friesian cows in Kazakhstan.

The aim of this study was to determine the effect of two mineral-vitamin premixes on the health status (blood biochemical parameters), milk yield and composition of Holstein-Friesian (HF) cows in Kazakhstan. The study was performed on Holstein-Friesian cows kept on the Bek Plus dairy farm in the village of Korzhynkol, Fyodorovsky District, Kostanay Region. Forty primiparous cows, selected from the herd, were divided by the analogue method into two groups: a control group (C) and an experimental group (E) of 20 animals each.