Changes in the composition of colostrum and milk of cows under the influence of feed additives - metabolism regulators

The article presents an assessment of the effect of feed additives - metabolic regulators, used animals according to the scheme developed by us, on the physico-chemical indicators of colostrum and milk. The experiment was conducted on 30 Holstein cows contained in the "Plemzavod Lenin "Atninsky district of the Republic of Tatarstan. The content of the mass fraction of fat, the mass fraction of protein, DSMR, the density of colostrum and milk was determined on the analyzer of milk quality “Laktan 1-4” in accordance with GOST 31980-2012. The use of feed additives based on propylene glycol, calcium salts of fatty acids and vitamin-mineral premixes developed by us in diets of dry and dairy cows for feedings leads to changes in the physicochemical composition of colostrum and milk. The use of vitamin-mineral premix P60-3/P in the final 15 days of the dry period in combination with the mentioned feed additives is accompanied by the maximum content of the mass fraction of protein in colostrum (6.0%), and extending the period of use of this premix to mass fraction of fat in colostrum to 5.41%, however, these changes were not significant. A significant decrease in the mass fraction of protein in the milk of cows in the control group (P