Subjects of research: Black-particolored cow breeds of different genotypes and milking technology by lactation phases.
Purpose of work: Development of technology of milking improvement by lactation phases, display of genetic potential of milk productivity of black-particolored breeds of cows of different Israeli Holstein genotypes and definition of biological peculiarities of their environmental adaptability.
Methods of research: zootechnical, technological and biological methods.
The results obtained and their novelty: The genetic potential of milk productivity of black-particolored breeds of cows of different genotypes of Israeli Holstein breed is found out. The milking level increased by 43-66 percent. For the first time their exterior peculiarities, the technology of milking improvement by lactation phases, environmental adaptability and their relation to productivity were studied.
Practical value: Receiving of different genotype animals by crossing of black-particolored breed of cows with Israeli Holstein breed, identifying of their productivity genetic potential at optimum conditions of their housing and feeding.
Forming of high-productive cattle-stock, environmentally adapted, tolerant to hot climate and gaining of milk productivity of 3900-4600 kg.
Degree of embed and economic efficiency: Results arc introduced in cattle stocks in farms Soliikh, Azizjan and Murat of Kibray District of Tashkent Region. The profit of 345,6-572,9 Thousand Sums was earned from each cow, profitability rate made 36.4-41.1%.
Field of application: Cattle-breeding farms specialized in dairy production in suburbs of Tashkent city.
