Abstract
E.I. Fedorovych, V.V. Fedorovych, I.Y. Semchuk, N.M. Fedak, L.V. Ferenents, N.P. Mazur, P.V. Bodnar, M.I. Kuziv, O.V. Fedorovych, T.V. Orihivskyi, B.V. Gutyj*, M.V. Slusar, M.D. Petriv and S.I. Fyl
The genetic potential and actual productivity of cows depend on their breed. In controlled farms, the higher expected and the actual yields were noted by the first-born cows of the Holstein breed. Expected yields of higher lactation in cows of both breeds were almost at the same level, but with higher actual productivity animals of the Ukrainian Black-and-White dairy breed. By degree of implementation, genetic potential in both controlled herds were the best cows of the Ukrainian Black-and-White dairy breed, at the same time above its value was observed in animals of Private joint-stock company "Plemzavod Stepnoy". We found that with increasing the share of Holstein heredity, the genetic potential of cows- first-borns in both herds increased, and the degree of its implementation decreased. There was a high advantage in realizing the potential genetic productivity of first-born lines P.F.A. Chifa and R.O.R.E. Elevation in Limited liability company "Veleten" and lines R.O.R.E. Elevation and K.M.I. Bella in Private joint-stock company "Plemzavod Stepnoy" above the same age cows of the other lines indicates the possibility of staffing of highly productive herds of animals of these lines. By breeding value by the yields of fathers of bulls, parents of cows, mothers of bulls, and mothers of cows in the second farm predominated the corresponding category of animals in the first farm. At the same time, the highest breeding value in both farms had the fathers of bulls, and the smallest – the mothers of cows, and therefore the contribution of paternal ancestors to the effect of selection by yields is much higher than maternal. Genetic progress on milking in Private joint-stock company "Plemzavod Stepnoy" was 89.8 kg, which is more than in Limited liability company "Veleten'" by 43.2 kg. The contribution of four categories of breeding animals of the Ukrainian Black-and-White dairy breed in genetic improvement of the herd Limited liability company "Veleten" was 1.5 times higher than similar categories of Holstein breed. Private joint-stock company "Plemzavod Stepnoy" although insignificant, but Holsteins made a more significant contribution to the genetic improvement of the herd. In controlled herds, animals were characterized by high genetic potential, which was realized by 84.7%. Higher Holstein cows were marked by expected and actual milk yields and the degree of realization of genetic potential – Ukrainian Black-and-White dairy breed. The highest breeding value in both herds was characterized by the parents of bulls, while the smallest – by the mothers of cows. Therefore the contribution of paternal ancestors in the effect of selection by milking was much higher than maternal. Genetic progress in yields in farms was 46,1 – 89.8 kg. The contribution of four categories of breeding animals of the Ukrainian Black-and-White dairy breed in the genetic improvement of the herd Limited liability company "Veleten" was 1,5 times higher than the contribution of similar categories of Holstein breed. In the Private joint-stock company "Plemzavod "Stepnoy", though insignificant, a more significant contribution to the genetic Holstein improved the herd.