Influence of the genotype on the morphofunctional properties of crossing the first calving
The article presents the results of studies on the morphological and functional properties of the udder cows for the first calving of a new intra-breed type of black-cattle «Karatomar», depending on the origin. Assessment of the morphological parameters of the udder influences the suitability of cows for machine milking. The prevalence of glandular tissue in the udder was determined in the descendants of bulls of Holstein breed of American selection. A general evaluation of the morphological features showed that the heifers of the bulls of the Holstein breed of American breeding Orbit 4078 and Lowrider 4129 were 0.96 and 0.74 points respectively superior to the heifers of the Holstein bull of the Yamal 975 of local selection. The daily yield of cows with a high evaluation of the morphological properties of the udder - the daughters of the bulls Orbita 4078 and Lowrider 4129 - was higher than that of the cows of the daughters of the Yamal bull 975 by 2.4 kg (10.04%) and 1.7 kg (7.11%). The intensity of milk yield in the group of offspring of the bull of local breeding was 1.82 kg / min, which is 4.9% and 6.0% lower than the heifers of American bulls. The analysis of the morphofunctional properties of the udder has shown that cows - heifers of bulls of Holstein breed of foreign selection have udders more suitable for machine milking.