ВЛИЯНИЕ ИНТЕНСИВНОГО ВЫРАЩИВАНИЯ ТЕЛОК НА ИХ РОСТ И ПРОДУКТИВНОСТЬ

Abstract

As a result of research aimed at improving the red steppe cattle, using the gene pool of Ayrshire and Holstein Red-and-White cattle, it was found that the resulting crossbreeds were distinguished by higher milk productivity. When studying the livestock, groups of animals with higher productivity rates were identified and formed in comparison with the average for the herd. Crossbred heifers of the first generation were intensively grown and inseminated at the age of 13-15 months when they reached a live weight of 360-380 kg. The effect of heterosis contributed to obtaining such a live weight. The average daily gain in live weight varied from 861 to 900 grams, both for individual age periods and for the entire growing period, the tendency for the superiority of crossbred heifers remained. In terms of milk productivity, crossbred Holstein Red-and-White heifers surpass their peers of purebred red steppe heifers in terms of milk yield by 586,8 kg or 11,3% (P>0,99), in terms of fat content they exceeded by 0,22% (P>0,99) and protein – 0,05% (P>0,99). Crossbred Ayrshire heifers of group II yielded in terms of milk yield to peers of group III by 76 kg, but in terms of fat content they were superior by 0,06, protein 0,15%. The amount of milk fat in the milk of cows II and III was at the same level of 214,8-214,9 kg and exceeded the purebred peers of group I by 34,2-34,3 kg (P>0,99), and the amount of milk protein – 16,2-21,6 kg (P>0,95).