REALIZATION OF PARENTAL INDICES OF COW PRODUCTIVITY IN DIFFERENT MILKING BREEDS AT BREEDING FARM "AGROFIRMA "PAKHMA"

Abstract

Combination of genotypes of main types’ genetic markers causes milk productivity in cattle. The article studies correlation between kappa casein genotypes (C3N3), beta-lactoglobulin (LGB), their complexes and milk production indices in cows bred under equal conditions at a breeding farm. The calculation of parental milk yield and fat indices between the three breeds showed a significant difference (P>0,999) of PCI of Ayrshire and Holstein cattle breed milk yield - 3395 kg, PCI of fat - 0,22%; between Holstein and Yaroslavl cattle breeds - 3200 kg, PCI offat - 0,16%. A significant difference of realization indices of protein between all three breeds was not stated. The highest realization ofparental milk yield index was stated - between Ayrshire and Yaroslavl cattle breeds- 113%, Holstein cattle breed - 88%. As for the fat and protein indices, all three cattle breeds showed a high realization of PCI from 98% to 109%. However, Holstein cattle breed showed the highest percentage: protein - 101%, fat - 109%. A significant difference of PCI realization of milk productivity in CSN3 and LGB genotypes was not stated. It was also stated that there is a tendency of high level parental indices realization when there is a higher number of B-allele variants in genotypes of cows.