PSI-B-29 - Breeding influence on dairy productivity of Kholmogory cattle

The Kholmogory breed of cattle is highly adapted to poor feeding and severe climate conditions of the northern part of European Russia, but a lack of dairy productivity also characterizes it. The study aims to measure the productivity of animals obtained by breeding Kholmogory and Holsteins cattle. Purebred Kholmogory (K1, n = 497), first generation` (K1/2×H1/2, n = 387), and second generation` (K1/4×H3/4, n = 384) hybrids were selected for the analysis. Dairy production for 305 days throughout 1st and 3rd lactations and also lifetime productivity were measured. Statistical processing was conducted using Statistica 10 software. The average milk yield of purebred` 1st lactation was 3501±35 kg with a fat content of 3.66±0.01%. The productivity of hybrids in the 1st lactation was higher by 728 kg (P < 0.001) with a fat content of 3.86±0.02% for K1/2×H1/2 and by 1030 kg (P < 0.001) with a fat content of 4.13±0.02 for the K1/4×H3/4 population. In the 3rd lactation, the productivity of K1 was 3948±51 kg of milk with a 3.73±0.02% of fat. This is 941 kg (P < 0.001) and 0.31% (P < 0.001) less than in K1/2×H1/2. During the same lactation in K1/4×H3/4, the average amount of milk was 5508±77 kg with 4.25±0.04% of fat. The maximum lifetime productivity was obtained from K1/2×H1/2. It made 19850±618 kg of milk and 799.6±25.3 kg of milk fat. In the K1 group, 14642±529 kg of milk and 552.6±20.3 kg of fat were obtained per life, and for K1/4×H3/4 14832±590 kg and 620.9±25.6 kg were obtained. The heterosis effect could explain the high lifetime productivity of first generation hybrids. This is consistent because the average economic use of K1 animals was 3.53±0.11 calving, while for K1/2×H1/2, it was 4.01±0.11. Further breeding with the Holstein led to a significant decrease in the economical use duration to 2.78±0.09 calving in K1/4×H3/4.