Biological parameters of economically useful signs of first calving cows of regional populations of the Russian Federation dairy cattle of Ayrshire breed

In the animal population in process of evolution there is a continuous change of genetic composition. Interaction of heredity, variation and selection determines the existence of populations. Currently, the selection applies to the whole breed population. Therefore, it is necessary to develop a methodological basis for the breed selection programs. Identification of biological parameters of the main economically useful signs of first calving cows of regional populations of domestic dairy cattle of Ayrshire breed is the purpose of these studies. It is established that the age of cows at the first calving ranges in the Southern Federal District (SFD) and Volga FD (VFD) from 25.5 and 25.7 months to 26.9 in the Northwestern FD (NFD); calving age from 2.30 years in the Central FD (CFD) to 2.82 years in the NFD; milk yield for the last completed lactation in all categories of farms from 7643 kg in 9 farms of the VFD to 6314 kg in 29 farms of the CFD, including Breeding Factories (BF) from 8312 kg in VFD to 6694 in the SFD; the content of milk fat and milk protein from 4,32 and 3,52% in the VFD to 3.95 % of fat in the SFD and 3,22 % of protein in the NFD. The highest value of variability of milk yield from cows in the SFD, and the content of fat and protein in milk, and yield in 100 days - in the CFA. More stable yield at Ayrshire CFA, the fat content in milk - VFD. The most diversity in live weight after the 1st calving in animals VFD. First calving cows of all FD have low heritability of service period, in VFD - of content fat in milk and in CFD - of daily milk yield and milk yield rate. For the rest of the signs observed average or high coefficients of heritability. Revealed a low positive correlation (+0,029) of milk yield with fat content in milk of the CFD. In contrast the high positive correlation of milk yield with protein content in milk of the VFD and CFD (+0,256 and 0,233) against the negative in the SFD, the lack of correlation of milk yield with a live weight after first calving in SFD (+0,024). It is necessary to develop separate breeding programs for regions of Ayrshire cattle breeding and correct data of electronic databases for the development of breed selection programs for the breed.

Ayrshire breed, diversity of micropopulations, variability, heritability, correlation

1. Басовский Н. З. Популяционная генетика в селекции молочного скота. - М.: Колос, 1983. 256 с. Ил.

2. Басовский Н. З. Методические рекомендации по разработке и оптимизации программ селекций в молочном скотоводстве / Н. З. Басовский, В. М. Кузнецов. - Л., 1977. - 87 с.

3. Пустотина Г. Ф. Применение методов популяционной генетики в племенной работе с крупным рогатым скотом / Г. Ф. Пустотина // Вестник ОГУ. - 2005. - № 12. - С. 89- 95.

4. Янчуков И.Н. Основные параметры селекционной программы совершенствования популяции черно-пестрого скота Московской области / И.Н. Янчуков, А.Н. Ермилов, С.Н. Харитонов и др. // Известия ТСХА. - выпуск 6. - 2011 г. - С. 127- 135.

5. Кузнецов В.М. Современные методы анализа и планирования селекции в молочном стаде. - Киров: Зональный НИИСХ Северо-Востока, 2001. - 116 с.

6. Ежегодник по племенной работе в молочном скотоводстве в хозяйствах Российской Федерации (2017) / И. М. Дунин, Х. А. Амерханов и др. // М.: ФГБНУ ВНИИплем. - 2018. - 274 с.

7. Сергеев С. М., Тулинова О. В., Селекционно-генетическая статистика - ВНИИГРЖ. Свидетельство о государственной регистрации программы для ЭВМ РФ, №. 2015663613, 2015.

8. Васильева Е. Н. Биологические и селекционные факторы повышения качества генотипа производителей айрширской породы скота на основе их генетической оценки / Е. Н. Васильева // Ученые записки Петрозаводского государственного университета. - 2018. - № 3 (172). - С. 67-71.