Аннотация
This study presents a comparative evaluation of different types of protein–vitamin–mineral supplements on growth performance of young Kazakh White-Headed cattle under pasture-based feeding conditions in Western Kazakhstan. The objective was to assess the effectiveness of the complex mineral-vitamin supplement “Felucen” and a protein–vitamin–mineral supplement (PVMS 20%) in diets of bull calves and heifers aged 4-6 months. The experiment was conducted under farm conditions using the principle of analogous groups (n=10 per group). The control group received a basal pasture-concentrate diet, whereas the experimental groups were supplemented with either Felucen or PVMS 20% at a rate of 80 g per head per day. The inclusion of supplements did not alter the dietary energy level but improved protein and mineral supply (phosphorus, magnesium, carotene). PVMS 20% increased average daily gain of bull calves by 26.8% (P<0.01), while Felucen increased it by 19.0% (P<0.05) compared with the control group. In heifers, the increase ranged from 4.5 to 4.9% (P<0.05). The results demonstrate a more pronounced growth-stimulating effect of PVMS 20%, likely due to its higher content of available protein. The use of protein–vitamin–mineral supplements under pasture feeding systems is a biologically and technologically justified approach to enhance growth intensity of beef cattle young stock. The use of protein-vitamin-mineral supplements increases growth intensity and improves the productive qualities of animals, which is important for increasing the efficiency of beef production under pasture feeding conditions.