REGULARITY OF THE FARMING USEFUL TRAITS IN ANIMALS OF THE UKRAINIAN BLACK-AND-WHITE DAIRY BREED BY ABSORPTIVE CROSSING

Abstract

A comparative assessment of the phenotypic manifestation of the main traits of milk productivity and reproductive ability of cows of different genotypes of the Holstein breed of "domestic selection", separated by the order of the Ministry of Agrarian Policy of Ukraine from the livestock of animals of the Ukrainian black-and-white dairy breed, obtained with an increased conditional proportion of blood in their genotype according to Holstein breed over 96.8% as a result of absorption crossbreeding, Holstein breed of foreign selection and Ukrainian black-and-white dairy breed was carried out. The animals were used under traditional and high-technological standards of feeding and maintenance. It was established that, on average, for 14 breeding farms (the first version of experiment), the milk yield of cows belonging to the Holstein breed of "domestic selection" for 305 days of the first lactation was 8605±330.1 kg on average and exceeded the analogues of the Ukrainian black-and-white dairy breed by 54 kg, and the amount of milk fat of cows of Holstein breed «domestic selection" amounted to 322.3±9.55 kg, and was 1.1 kg higher than the analogues of the Ukrainian black-and-white dairy breed. The amount of total protein in the milk of Holstein cows of «domestic selection» was 280.5±12.79 kg and was equal to this indicator in cows of the Ukrainian black-and-white dairy breed (280.7±6.35). The difference between the indicators of the studied traits was not statistically significant (td=0.08–0.12, at Р<0.90). No difference was found in the content of fat and protein in milk between animals of both breeds. For 305 days of the last completed lactation, the advantage of Holstein cows of "domestic selection", on average, over cows of the Ukrainian black-and-white dairy breed was: milk yield +34.6 kg, milk fat +0.1 and protein +1.2 kg, which is statistically not significant (td=0.08, P<0.90). According to the traits of reproductive ability, Holstein cows of "domestic selection" were significantly (by 10.3 days) inferior to their counterparts. The output of calves from Holstein cows was 77.86±2.48 heads, and in the Ukrainian black-and-white dairy breed – 83.64±1.99 heads, which is 5.8 fewer calves per 100 cows. In breeding farms that simultaneously breed animals of the Holstein breed of foreign selection and the Ukrainian black-and-white dairy breed, at a high level of feeding (the second version of experiment), Holstein cows of foreign selection in 305 days of the first lactation exceeded their counterparts of the Ukrainian blackand- white dairy breed in milk yield by +939.8 kg, milk fat – by 33.4 and total protein – by 27.5 kg. It is characteristic that the content of fat and protein in the milk of Holstein cows of foreign selection was also lower than, that of the analogues of the Ukrainian black-and-white dairy breed by 0.01–0.05%, respectively. The level of reproductive function of Holstein cows of foreign selection, even at a high level of feeding, was also significantly lower, compared to that of animals of the Ukrainian black-and-white dairy breed. The duration of the service period in Holstein cows was 128.0±9.52 days and was 9.2 days longer than the analogues of the Ukrainian black-and-white dairy breed, and number of calves was lower compared to the analogues by 3.2 heads per 100 cows.