Affiliation:
1. Vitebsk State Academy of Veterinary Medicine.
Abstract
Over the past decades, in many countries with developed dairy cattle breeding milk yield per cow per lactation has significantly increased, and period of cow productive use has been significantly reduced. The average duration of cow use in many countries is 2.5–2.8 lactations, and this is not enough for sustainable implementation of genetic potential of animals, which is revealed only at the 5–6th lactations. There is an increase in milk productivity and improvement of exterior type of black-and-white breed of cows in the Republic of Belarus, which is due to the use of Holstein cattle with outstanding milk productivity potential and a well-defined milk exterior type, however, as in other countries, there is a decrease in cow use period. The paper presents the results of monitoring of production use of cows in dairy herd conditions with highly productive breeding livestock. 5670 Holsteinized cows of Belarusian black-and-white breed were evaluated in two herds. The main causes of cows culling are determined, effect of genetic (blood level of Holstein breed, level of fathers and mothers performance) and paratypic (age of the 1st calving, level of heifers milking, inter-calving period, service period, results of the first insemination) factors for the life-long milk performance and cow use period. Correlation and heritability of indicators of productive longevity of cows is determined. A system of arrangement and breeding measures to improve longevity of highly productive livestock has been developed. Implementation of the developed system will allow to improve the integrated indices of breeding value of bulls and dairy cows and increase profitability of milk production by increasing the period of use of dairy herd maternal livestock. Acknowledgments. The work was carried out as part of the state research and technical program “Agropromcomplex – sustainable development” for 2011–2015 sub-task 3.3.1 on topic “Develop system of breeding work with maternal livestock of Holsteinized dairy herds of different productivity levels”.
Publisher
Publishing House Belorusskaya Nauka