Assessment of the influence of the maternal genotype on the realization of the productive potential of Holstein cattle in the conditions of the Novosibirsk region
Bulletin of NSAU (Novosibirsk State Agrarian University)
An analysis of the productive qualities of mothers cows and their offspring, obtained from different fathers, showed that the contribution of parents to the formation of milk productivity is unequal. Intensive selection of bulls-producers leads to fixation of homozygotes at the loci associated with traits of milk production, which increases their influence on offspring. The strength of the influence of the father's factor on milk yield, milk protein and live weight of daughters was 6,
... rs was 6, respectively; 14 and 16%. The productivity level of mothers did not significantly affect the productivity of their daughters. High-yielding offspring can be obtained from low-yielding cows. Daughters surpassed their mothers in milk yield, but inferior in fat milk. The proportion of deviation from the theoretically expected productivity of daughters (milk yield per 305 days), which is caused by the influence of the maternal genotype, in the groups of Auckland No. 426436885, Showman No. 831842 and Euclid No. 831491, respectively, was 15.8; 27.5 and 30.4%. The correlation coefficient between the milk yield of mothers and daughters was + 0.25 (p <0.05), and body weight correlated at the level of +0.3 (p <0.01). In the groups of daughters, butterfat is associated with milk yield (r = - 0.5) and milk protein (from +0.34 to +0.67). For mothers, the relationship between these indicators was lower. It is possible that half-siblings have stronger genetic links between traits than unrelated mothers. Genetic diversity in milk yield (h2 = 0.6) and live weight (h2 = 0.5) was established. Repeatability coefficients for fat and milk protein were at the level of 0.35. The productive potential of the breed depends on the combinational compatibility of the parents, their contribution to the formation of complex quantitative characteristics of productivity.