Protein-nitrogen metabolism parameters of high-producing cows of different physiological states when feeding a tanin-containing additive

The article presents the results of a study of the effect of tannin-containing feed additive “Tanamin Zn” (hereinafter - tanamine) on the values of some protein-nitrogen metabolism indices in the blood of deep-bodied and new-bodied highly productive black-and-white cows. Tanamine includes chestnut extract, zinc (in the form of a hydrate of the chelate complex of zinc with glycine), methionine and lysine hydrochloride. In the first experiment, the cows of the control group did not receive the supplement, while the experimental group was fed it during the dry period at a dose of 20 g/head/day. In the second experiment, during the dry period, tanamin was fed to the control and experimental groups, and after calving - only to the experimental group. The supplement dose before calving was 20 g/head/day, and after calving (for 60 days) - 30 g/head/day. By the end of the tanamin feeding period in the first experiment (15 days before calving), a reliable increase in the concentration of total protein and globulins was shown relative to intact animals against the background of a decrease in albumin, creatinine, AsAT and AlAT activities. During the aftereffect period (15 days after calving), significantly higher levels of total protein and globulins and low levels of creatinine, urea, as well as AsAT and AlAT activity were established, and by the 30th day, high concentrations of total protein, globulin fractions, AsAT activity and low levels of urea were established. Continuing to feed tanamine after calving (second experiment) contributed to an increase in total protein and globulins with varying degrees of reliability on the 15th and 30th days against the background of a decrease in AsAT and AlAT activity.