PHENOTYPICAL AND GENETIC INDICATORS OF EXTERIOR DETAILS OF GOLSTTINIZED MILK CATTLE OF KAZAKHSTAN
Obtaining highly productive animals adapted for use in specific climatic and production conditions is the main task of breeding work in dairy cattle breeding. When creating highly productive herds, great attention should be paid to the assessment of the exterior of animals, the characteristics of which have a certain connection with the period of production use of cows, which in turn affects the level of profitability of dairy cattle breeding. Timely identification and exclusion from the herd of animals with serious defects and exterior defects allows to prevent their accumulation and spread in the breed, since the latter can lead to a decrease in productivity and other undesirable and difficult to correct consequences [1, 2, 3, 4]. The article presents the results of the assessment of the physique type of holsteinized first-calf cows based on 19 exterior features. As a result of research, it has been established that animals are quite heterogeneous in type and body build, with the most uniform in height (Cv = 12.4). The greatest variation of symptoms is also observed in the location of the front and rear nipples (CV = 48.3 and 40.4, respectively). The calculated coefficient of heritability for each article of the body showed that the exterior attribute “Udder bottom position” (h = 0.51) turned out to be the most inheritable, the smallest coefficient was determined by the angle of the hooves (h = 0.12). High rates of cow's milk yield correlation were established with the sign “Width of the back portion of the udder” (r = 0.66). On the whole, the conducted studies allowed determining the exterior-constitutional body type of the modern population of Holstein cattle and the prospects for breeding to improve the identified poorly pronounced exterior signs.