Influence of immunogenetic factors on the reproductive ability and productive longevity of Red-and-White cows

Currently, one of the most relevant areas of scientific research in the livestock industry is the identification of certain genes that affect the productive and reproductive qualities of cattle by early animal testing using erythrocyte antigens as polymorphic markers. The influence of immunogenetic factors on the reproductive ability and productive longevity of Red-and-White cows has been studied in this work. A database was formed in the farm of the Krasnoyarsk Territory using the program "Selax" to conduct research. This program includes information on the productive longevity, milk production and reproductive performance of 305 cows retired from the herd from 2019 to 2022 with blood group immunogenetic testing results. The influence of the composition and occurrence of the antigens with a sample frequency of 0.3 or more on the reproductive performance of cows, lifetime milk production and longevity was analyzed. Cows were divided into carriers and non-carriers of each antigen. As a result, it was found that the earliest age of the first calving was observed in the cows carrying antigens Y` and E (–0.9 and –0.8 months), and the shortest service period was in the carriers of antigen P` 2 (–15.7 days). The longest period of economic use was noted in the cows carrying antigens V and O` (+5.9 months), the highest lifetime yield was in the carriers of antigens V and W (+6036 and +4142 kg). The share of the effect of these antigens was 1,3–4,3%. It is necessary to take into account the influence of the antigenic composition of blood groups when carrying out breeding work to increase the period of economic use of Red-and-White cows and improve their reproductive ability.