INFLUENCE BLOOD SHARE AND THE LINEAR ACCESSORY ON INDEXES OF DAIRY EFFICIENCY OF COWS

Abstract

Blood inflow of Holstein breed in Mari El cattle breeding, which began in 80s of the last century, had a positive impact on the dairy productivity of Black-and-White cattle. The research explores the impact of Holstein breed bloodline and lineage on the main indicators of cows’ dairy productivity in OAO Ovoshchevod. The productive age increasing, the live weight of cows in the main herd increased as well while the animals were relatively small. The cows of the eighth and ninth calves had the maximum live weight. On average, the cows with the third complete lactation (6791.5 kg) had the highest milk yield. The mass fraction of fat was on average higher than the basic fraction and was equal to 3.71%. The increase of milk fat concentration was observed in cows of the fifth and sixth lactations, with the offsprings of Black-and-White bull lines being the most fatty. There is a direct correlation between milk yield and the degree of blood flow in the Holstein breed. The fattiest milk cows were those with a blood content of 19%, while the cattle with a blood content of 75% had the lowest fat concentration in milk. According to the hospitalization data, most of the cows in the herd (including the first heifer cows) belong to the R. Sawring line. The female offsprings of Adam, Rikus and M. Chiftein bulls differed in the most productive longevity. The most abundant were cows belonging to M. Chiftein line. Female offsprings of Black-and-White bulls were inferior to the Holstein ones in average by 324 kg of milk. This feature was traced from first to fifth lactation. In the lactation section, the most fatty-milk cows of the Rikus and M. Chiftein lines were the fattest. As the share of blood in the Holstein breed increased, the milk yield per cow in the main herd increased as well. Thus, for cows with blood content of 18.75%, the average milk yield for all lactations was 6313 kg of milk. Further blood inflow of Holstein bulls led to this parameter increasing by 4% on average for cows with blood content of 25 and 37.5% for Holstein breed.