Productive features of the first heifers of the red steppe breed under different systems of housing and forming of production groups

Abstract The purpose of the research is to establish the productive qualities of the first heifers of the red steppe breed with different technologies of housing and forming a production group of newly-calved cows. Intergroup differences in the milk yield of the first heifers were established, which amounted to 176 kg of milk in favor of individuals who lactated separately from adult cows (P>0.95). The yield of protein and fat during lactation also prevailed in the experimental group of heifers by 3.5-3.8%. According to the milk content index, the first heifers kept together with adult livestock were inferior to the individuals of the experimental group by an average of 1.4%. The differences in the content of first heifers in the summer period were expressed in the superiority of milk yield of first heifers, which were grazed on pastures, during the pasture period at the level of 262 kg (P>0.95), provided them with superiority in milk production for the entire period of first lactation by an average of 289 kg of milk (P>0.95), as well as in yield milk fat and protein. As a result, the milk content index of the first heifers of the experimental group reached 1225 kg against 1161 kg in the control (P>0.95).