Monitoring of harmful mutations in cattle in the conditions of the Moscow region

A sharp improvement in breeding work in animal husbandry requires the development of measures to control the genetic usefulness of breeding animals. For this purpose, cytogenetic testing of breeding stud-animals for various kinds of chromosome disorders has been carried out. The breeding stock of breeding dairy herds is currently not covered yet by cytogenetic monitoring, which in the future should become an element of breeding work. Since cows are the main reproducing part of the herd, it is important to evaluate them in terms of genetic and reproductive potential. However, the population-statistical features of individual highly productive cattle herds in terms of unconstitutional karyotypic variability are still unknown. We have determined a list of signs of unconstitutional karyotypic variability in cows with milk yield of more than 8000 kg of milk per lactation in the best farms of the Moscow region. Signs of genetic risk were taken into account - aneuploidy, polyploidy, structural abnormalities of chromosomes in cows, then, based on the results obtained, a comparative analysis of reproductive functions in the same cows was carried out. It is established that in each herd among cows with high productivity there are limits of interindividual variability in the level of unconstitutional karyotypic anomalies. According to the frequency of occurrence of aneuploid cells, cows of Petrovskoye BREEDING Plant JSC had a significant superiority - 10.14%, against 7.11% in cows of Povadino BREEDING PLANT JSC and 4.03% in cows of Vohrinka Agroindustrial Complex LLC, the difference was 3.03% and 6.11%, respectively. The proportion of polyploid cells was also high in cows of JSC Petrovskoye BREEDING Plant - 0.81%, a significantly significant difference was revealed only when comparing cows of JSC Povadino BREEDING PLANT 0.51% (0.30%).