Influence of live milk yeast on milk productivity and reproductive traits of fi rst-calf heifers

Current technologies in dairy cattle breeding are aimed at finding solutions to increase cow productivity and optimize reproduction rates. Therefore, in recent years, a wide range of feed additives has been used to enhance the realization of the hereditary potential of animals, a comprehensive study of which is relevant and new. The purpose of the work was to evaluate the effect of live milk yeast “ Kluver Pro” on milk productivity and reproductive traits of fi rst-calf heifers of Holstein breed. In order to carry out the experiment three groups of animals (a control group and two experimental groups) of 12 animals each were formed. The reference period of the experiment had a duration of 140 days (20 days before calving and 120 after calving). Against the background of the basic ration, the studied yeast probiotic was fed to the heifers and first-calf heifers of the 1st and 2nd experimental groups. The results of the research showed that the use of the yeast probiotic “Kluver Pro” maked it possible to increase the feed intake, increase the energy and nutrient content in rations, which ensured an increase in milk productivity by 8.4 and 13.8 %. In the milk of cows of the 1st and 2nd experimental groups, the mass fraction of protein and fat significantly increased. The increase in productivity of fi rst-calf heifers was achieved by reducing feed consumption for products. It has been found that it is most advisable to introduce deep pregnant heifers of 20 g/head into the ration per day of yeast probiotic, freshly calved fi rst-calf heifers – 100 g/head/day, and during their increasing the milk yield period (21–120 days of lactation) – 20 g/head.