The black-and-white breed young growth muscle tissue nutritional value and its crossbreed with Holsteins

The purpose of the study is to determine the effect of crossing Black-and-White cattle with Holsteins on the chemical composition and yield of food protein, extractable fat from the muscle tissue of the carcass of young animals of different genotypes. Tasks: to establish the chemical composition of the muscle tissue of young animals of different genotypes, the gross yield and nutrients and the energy value of the muscle tissue of the carcass of purebred and crossbred bulls and bulls-castrates. Objects of study: purebred bulls (Group I) and Black-and-White steers (Group III) and its first-generation crossbreeds with Holsteins (Group II - bulls, IV - castrated bulls) in Kolos LLC, the Orenburg Region. To assess the nutritional value of muscle tissue after the control slaughter of 18-month-old young animals, its samples were taken, the chemical composition was determined according to generally accepted methods, the nutrient yield and energy value were calculated. The obtained results and their analysis testify to the positive effect of crossing Black-and-White cows with Holsteins on the nutritional value of the muscle tissue of hybrids. At the same time, the mass fraction of dry matter in the muscle tissue of crossbred bulls and bulls-castrates increased by 1.17 and 0.50 %, respectively, extractable fat - by 0.19 and 0.23, protein - by 0, 96 and 0,24 %. Intergroup differences in the mass fraction of nutrients in muscle tissue led to its unequal energy value. Bulls of group I were inferior to crossbred bulls of group II in terms of energy concentration in 1 kg of muscle tissue by 238.8 kJ (5.4 %), and the energy value of the entire muscle tissue of the carcass - by 219.0 MJ (27.5 %). At the same time, crossbred bulls - castrates of group IV surpassed purebred peers of group III in terms of energy concentration in 1 kg of muscle tissue by 130.7 kJ (3.0 %), the energy value of the entire muscle tissue of the carcass - by 86.1 MJ (11.0 %).