PRODUCTIVE LONGEVITY OF BLACK-AND-WHITE COWS IN DIFFERENT ECOLOGICAL AREAS OF THE URAL ZONE

The ecological situation in a particular area has a huge impact on the growth and development of all living organisms. The paper demonstrates a comparative analysis of the productive longevity of Black-and-White cows in the Kurgan and Sverdlovsk regions. It has been established that the yield of cows aged 1-2 lactations at the enterprises of the Kurgan region is 14.8%, and in the Sverdlovsk region - by 20.3% more. The share of cows died within the period from the fifth to the sixth lactation in the Kurgan region exceeds that parameter of the Sverdlovsk region by 18.1%. The most common causes of cow death in the ecological zones are leg diseases (13.9-17.6% of cases). Among the most common reasons for animals death in the Kurgan region are metabolic diseases, low milk productivity, difficult births and complications, osteoarthritis; in the Sverdlovsk region these reasons are seen as diseases of the breast, digestive organs, deficiencies of the exterior. As a result of infectious diseases, the animals in the Kurgan region were eliminated in the amount of 3.0%, and in the Sverdlovsk region they were not eliminated. Cows grown in the Kurgan region with lifelong milk yield of up to 5 thousand kg of milk had an annual milk yield of 2205.0 kg, which is 9.8% higher than in the same group of animals in the Sverdlovsk region. The difference in this case varied from 172.0 to 2821.0 kg of milk per lactation on average.