| Popis: |
Due to the intensifi cation of the cattle breeding industry, there is a need to fi nd ways and available methods to increase production and improve the quality of beef based on the use of existing breeding stock of dairy cattle. The success of industrial crossbreeding depends primarily on the correct selection of breeds and their compatibility. The purpose of the research was to study the growth and development of purebred young cattle of Black-and-White breed and crossbreeds with Hereford breed in the Leningrad region. Research and production experiment has been carried out in the training and research farm “Pushkinskoe” of the St. Petersburg State Agrarian University. In the control group purebred animals of Black-and-White breed (9 heads steers and 7 heads heifers), in the experimental group half-blood animals (9 heads steers and 7 heads heifers) have been selected obtained as a result of crossbreeding Black-and-White cows and Hereford sires. The researches have been conducted from birth to 18 months of age. Researches have shown that the crossbreed young animals in comparison with purebreds were distinguished by expressed meat type of physique, a squat body with a welldeveloped back, a fairly wide and deep chest and a strong bone structure. Crossbred animals have been characterized by increased growth intensity. Steers and heifers outperformed their Black-and-White herdmates in terms of daily live weight gain overall over the study period by 170,6 g or 18,8 % , and 130,2 g or 15,6 %, respectively (P ≤ 0,01–0,001). According to the research results, it is recommended that to increase the volume of beef production and more fully realize the productive potential of cattle in the Leningrad region, it is necessary to conduct industrial crossbreeding of holstinized Black-and-White cattle with Hereford cattle. The resulting crossbreed young animals should be raised and fattened up to 16 months of age when steers reach a live weight of 540 kg and feed expenditures per 1 kg of live weight gain of 6,4 EFU, and heifers more than 480 kg and 6,9 EFU, respectively. |
