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. The diets fed to group E cows were supplemented with LI-R 18 PRO and PANTO^® Mineral R-77 Premium mineral-vitamin premixes. The premixes positively affected cow productivity and blood biochemical parameters, whose values were higher in group E than in group C. Higher levels of glucose, albumins and globulins exerted a beneficial influence on the health status of cows. No cases of lameness or metabolic diseases were recorded in group E. The yields of milk, protein and fat were higher in group E than in group C. Dietary supplementation with two premixes had no significant effect on the chemical composition of milk, including the values of the following parameters: somatic cell count (SCC), dry matter (DM), lactose ($L_{\mathrm{se}}$), casein ($C_{\mathrm{in}}$), acidity ($A_{\mathrm{ty}}$), lactic acid (LA), density ($D_{\mathrm{ty}})$, free fatty acids (FFAs), glucose ($G_{\mathrm{se}}$) and urea ($U_{\mathrm{ea}}$).