Abstract. The aim of the research is a comparative assessment of the morphological and functional properties of the udder, productive longevity of cows of Black-Mottled and Simmental breeds. Methods. The work was carried out on the basis of an agricultural enterprise of the Tyumen region, where a loose method of keeping cows and voluntary milking by a robot is used. In the first group – cows of Black-Mottled breed, in the second – Simmental. Results. Cows of the first group of the Black-Mottled breed had a uniformly developed udder with an index of 45.1 % and were superior to animals of the second group of the Simmental breed: in girth by 7.2 cm (5.4 %) (p < 0.001) and width by 1.0 cm (5.0%) (p < 0.001). The indicator characterizing the capacity of the udder in animals of the black-mottled breed is greater than in simmentals by 295.2 cm2 (10.0 %) (p < 0.05). The difference in the rate of milk yield of cows was 0.05 kg / min (2.3 %) in favor of simmentals. The period of production use of Black-Mottled cows is longer than this indicator in simmentals by 0.4 lactation (p < 0.001). Animals of the Black-Mottled breed gave 2471.0 kg (p < 0.001) more milk over the entire period of use compared to animals of the Simmental breed. In addition, in Black-Mottled cows, the amount of milk fat and milk protein during the life period exceeds simmentals by 86.3 and 72.3 kg (p < 0.001). Novelty. When using the developed method of selecting highly productive cows, it makes it possible to get more milk from cows per day by 1.4 kg (6.7 %), for 305 days – by 268.1 kg (5.4%), for the period of life – by 1684.4 kg (9.7%). This method allows you to extend the period of economic use of the dairy herd by 0.4 lactation (14.8 %).
Effects of Canola Oil Dilution on Anhydrous Milk Fat Crystallization and Fractionation Behavior