Formation of Productive and Technological Qualities of Red-and-White Cattle during Ontogenesis with Different Feeding Levels
The aim of our research was to study the formation of productive and technological qualities of the Red-and-White cattle with different levels of feeding. For the experiment, two groups of ten bull-calves were formed: control (group I) and experimental (group II) ones. It was also formed two groups of twenty heifers: control (group iIi) and experimental (group IV) ones. The nutritional value of the diet in the experimental groups was higher by 7.0%. Bull-calves from the group II surpassed the group I in the live weight by 10.1 kg at 6 months, by 14.5 kg at 9 months, by 21 kg at 12 months, by 25.5 kg at 15 months. For heifers, these differences were 11.8, 16.3, 19.1 and 21.9 kg, respectively, and at 18 months the superiority was 25.2 kg. Bulls from the experimental group were superior to their counterparts in the control group in the pre-slaughter live weight by 5.3%; in the carcass mass by 8.2%; in the slaughter weight by 8.3%; in the output of carcasses by 1.4%, in the slaughter yield by 1.5%, and in the content of amino acids by 2.7-7.9%. Increasing the energy level of feeding during young age contributes to the harmonious development of animals bodies. It is confirmed by higher values of measurements of heads of femur and ischial tuberosities, width, depth and girth of chests of the animals from the experimental groups. Heifers from the experimental group were inseminated at the age of 16.4 months (492 days), which is 1.5 months (44 days) earlier than heifers from the control group. Live weight of cows at first calving in group IV was 544 kg that is higher by 23 kg than in group III. For 305 lactation days, it was obtained on the average 6543.4 kg of milk from the cows of the experimental group. It is 573.3 kg higher than from the control group. The absolute yield of milk fat and protein in the experimental group IV were higher by 16.1 and by 26.7 kg, respectively.