Comparative characteristics of reproduction qualities and chemical composition of milk of sows of Yorkshire breed and their mixtures

Scientific and production experiments on the study of the chemical composition of pig milk were carried out at the request of the management of the pig-breeding division of Vostochny LLC at the TATMIT Agro production site in the Sabinsky district of the Republic of Tatarstan. For the experiments, groups of sows were formed, kept in individual cages, for 28 days of the lactation period, with the same feeding conditions. The content of the mass fraction of fat in milk from 10 to 28 days of the lactation period in the Yorkshire breed decreases from 10.17 to 6.73%, in the Yorkshire × Landrace crossbreeds from 9.15 to 3.09%, respectively. The mass fraction of protein in milk and SOMO of purebred Yorkshires changed from 4.73 to 3.37% and from 12.82 to 9.14%, in crossbred sows from 3.61 to 3.22% and 9.37 to 9%, respectively. In terms of the chemical composition of milk, purebred sows exceeded crossbreeds throughout the suckling period, but the live weight of weaned piglets was 340 grams less and equaled 5.58 kg.