Variability of milk protein in holshtinky cows of the Kuzminsky SPA (K) breeding herd in connection with the productivity of their mother ancestors and the chemical composition of milk

Today, in our country, the protein content is not taken into account by pedigree and commercial farms when selling whole milk, or it is not taken into account to the proper extent. The level of value of a raw product for dairies is dictated mainly by its quantity and fat content, a little less often - by the content and composition of lactose. However, along with the above, protein invariably remains the most valuable component of milk. Due to the relatively high digestibility and the content of all essential amino acids, protein in selection and breeding work with dairy cattle should be given special attention. Due to the irrefutably high biological value of protein, the study of its variability as a sign and connection with many other characteristics of the raw product remains relevant. Many authoritative scientific works have established the nature of the relationship between protein content and the main, most frequently studied parameters of milk productivity. Its dependence, for example, on the indicators of the chemical composition of milk has been little studied at the moment, and we raised the question of the existence of this connection. We were also interested in identifying the degree of influence of the indicators of maternal ancestors on the trait of interest to us, taking into account the fact that when predicting the level of productivity in a herd, attention is often focused on the productive qualities of female ancestors on the part of the father.