Growth rate of purebred and crossbred bulls and castrates
The aim of the study was to assess the effect of crossing black-and-white cattle with German breeding Holsteins on the growth rate of young animals of different genotypes. The animals were monitored from birth to 18 months of age. From birth to 6 months of age, young animals of all groups were fed milk and skim milk by hand; from 1.5 months of age, hay and concentrates were introduced into the feeding ration; from 6 months of age until the end of the study, young animals were kept at the feedlot. According to the results of the study, it was found that the absolute increase in live weight of black-and-white gobies for the period from birth to 18 months of age was 491.7 kg, its half-breeds with German Holsteins (½ Holstein × ½ black-and-white) - 526.8 kg, castrated bulls of the black and white breed - 466.7 kg, crossbred castrated bulls (½ Holstein × ½ black and white) - 485.3 kg. Similar intergroup differences were noted in the average daily gain in live weight. Over the 18-month period of rearing, the growth rate of purebred bulls of the black-and-white breed was 910 g, crossbred bulls - 975 g, purebred bulls-castrates - 844 g, crossbred bulls-castrates - 899 g, relative growth rate - 178.44, respectively; 178.94; 177.35; 178.06 %. At the same time, the coefficient of increase in live weight with age in purebred young stock of the black-and-white breed at 18 months. was 17.55, her hybrids - 17.99, purebred castrated bulls - 16.66 and crossbred castrated bulls - 1.23.