CREATION OF A HIGH PRODUCTIVE HERD OF GOLSHTA CATTLE IN THE CONDITIONS OF THE "KUBAN" FARM
The article presents the features of economically useful characteristics of mothers and fathers of the Holstein breed belonging to the Vis Back Aydial and Reflection Sovering lines, from which replacement heifers were obtained for further research. The conditions of feeding and keeping cows in the sub-experimental groups were the same. In accordance with the ration, cows of both groups received corn silage 17.4 kg, alfalfa haylage 6.7 kg, alfalfa hay 0.6 kg, barley straw 0.6 kg, compound feed 10.9 kg. The diet included 0.18 kg of premix for lactating cows. The fodder ration contained 19.07 kg of DM and 197.12 OE, MJ. The productivity of mothers of replacement heifers descended from Bourbon bulls 3126887563 and Stound 3125079219 did not differ significantly. Differences in milk yield were 175.5 kg, they are not reliable, td = 1.27. From the mothers of heifers in the experimental group, 9660.1 kg were milked. From mothers of heifers from Bourbon 9484.6 kg. The average duration of lactation activity in mothers of heifers descended from the Stound bull was 321.7 days, in peers descended from Bourbon - 314.5 days. The differences are not significant, td = 1.44. For artificial insemination of experimental cows, the seed of bulls - producers of different lines was used. Differences in beta and kappa casein were found in breeder bulls whose sperm were inseminated in the experimental groups. The Bourbon bull has significantly more differences in recessive genes. Breeder bulls used were evaluated by the unequal number of daughters. Breeder Stound is rated at 104 daughters in 34 herds, Bourbon is rated at 112 daughters in 33 herds. In terms of beta-casein, the breeder bull, whose sperm were inseminated in the control group cows, is inferior to the peer experienced in the first indicator of A1 milk protein. Milk with A2A2 index is more valuable than a similar product with A1A2 index. The breeder of the control group has the same BB alleles for kappa-casein. Studies have established that mothers cows belonging to the Vis Back IDial and Reflection Sovering lines have a sufficiently high genetic potential for milk production. The breeding bulls used are matched to the cows in accordance with the zootechnical requirements for pairing