The adaptive value of cattle in the breeding of Ayrshire breed

Abstract

In the stables and pasture system, the success of the formation and development of herds on new farms is determined by the adaptive response and viability of cattle obtained in different countries and breeding systems, which was the purpose of the work. The object of the research was a herd of Ayrshire cattle, originally formed by heifers from 15 farms of the Leningrad region (n=843), Finland (n=684), Swedish red cattle of Sweden (n=115), as well as their reproduction - the first and second generation. Cattle of the Leningrad selection, with a similar duration of productive life (41,7…42,7 m.) and the number of calving (3.10...3.29) exceeded the Finnish and red-Swedish breeds in the number of effective daughters of the first reproduction introduced into the herd by 9.9...17.9%. The advantage of domestic genotypes is provided on the one hand by the increased number of cows of mothers by 4,9...6,8%, and on the other by the smaller share (-7,6...-8,1%) of cows with only one effective daughter. Milk productivity on average for all lactation and the number of offspring of female have a positive conjugation. Thus, cows that had no daughters or one daughter in the herd on average for all lactation were inferior in milk yield to mothers by -3553...-1103 kg (P≤0.95...≥0.999), as well as peers who had several daughters by 167..406 kg (P≤0,95...≥0,99). Thus, the Ayrshire cattle of domestic selection surpasses import on reproductive ability, relative number of effective mothers and daughters. In selections for cultivation it is necessary to use bulls with high adaptive value having disposal of young growth to 3 months no more than 6%. During the period of adaptation and acclimatization, the conditions of keeping and feeding should ensure the productivity of cows at the level of mothers, with an acceptable reduction in milk yield of not more than 12%.