Аuthor: V. F. GRIDIN, doctor of agricultural sciences, professor,
Ural State Agricultural University (42 K. Libknehta Str., 620075, Ekaterinburg; tel: +7 (343) 371-33-63)
Abstract: The Holstein species of large livestock on the number of livestock and milk productivity occupies the leading position in the entire world. For increasing the milk yields of aboriginal species in practice all countries use genotype of animals of this species, not taking into account that in the leading countries of milk cattle breeding the selection of animals is conducted taking into account different indices. Therefore use in the selection of Holstein animals without taking into account these special features frequently leads to the problems with the physiological state, the reproduction and to weakening the exterior of animals. Thus, with the use of genotype of Holstein animals necessary to consider the country of the origin of imported animals and those special features on which in them is conducted selection. In this article it is established that the heifers of German selection under the conditions of unrestrained technology exceed on the milk productivity of their analogs from Hungary, beginning from the first days of lactation, while as a whole during entire lactation period difference is 331 kg of milk with the equal content of fat in the milk. The indices of the exterior of heifers, studied by us in the correspondence with the recommendations regarding the estimation of build, and have an interrelation with the milk productivity. It is established that the heifers of Hungarian selection are had the sufficiently high positive connection of milk yield with the width of breast and a height in the sacrum, but negative — with a height in the withers, the width in the ischial mounds and the width in maklokakh. In this case, in the heifers of German selection is noted the higher positive interrelation of milk yield with a height in the withers, the depth of breast and the width in the ischial mounds.
Keywords: cow-heifers, milk yield, measurements, correlation, German genotype, Hungarian genotype, loose technology.
