The dynamics of number, indices of productivity and economic use in the breed populations of dairy cattle
The article presents the results of monitoring the number of livestock, the indices of dairy cows productivity and the period of their economic use in the populations of Ayrshire, Holstein, Kholmogory, Black and White, Yaroslavl breeds in all categories of farms of the Vologda region. Based on the data from yearbooks on breeding on dairy cattle breeding farms of the Russian Federation the dynamics in the number of evaluated cattle and cows according to their breed populations for 2012-2016 has been defined. The reduction of the total population by 17.51 thousand heads has been revealed, which amounted to 96.66 thousand heads and in cows the reduction by 4.41 thousand heads has been noted, which amounted to 62.34 thousand heads. A similar trend is observed in all breed populations. On the basis of the data on cows productivity the increase in milk yield in different breeds ranging from 294 to 1242 kg of milk has been defined. The indices of fat and protein content were changing during the analyzed period in the populations depending on the breed. There was a trend of decreasing the age of cows in calvings. For five years the average age of cows decreased from 2.88 to 2.80 calvings. Similar dynamics is observed in the dropping the animals out of the herd. The reduction of the period of using cows for all breeds ranged from 3.78 to 3.76 calvings. In the population of Black and White breed the period of economic use decreased by 0.12 calvings. Therefore, improving dairy cattle populations in the Vologda region should be directed to increasing the age of cows in calvings. Special attention should be paid to breeding the animals of Black and White breed numerous populations with the aim of increasing the period of their economic use.