REARING FEATURES OF SIMMENTAL × AIRSHIRE × HOLSTEIN CROSS BREEDS

The paper presents data on growth characteristics of three cross-bred Simmental × Ayrshire × Holstein heifers. The study of growth and development of three crossbred animals showed that there is a tendency of more intensive growth of crossbred young animals of 1/8c + 1/8a + 3/4kpg and 1/16c + 1/16a + 7/8kpg genotype since the age of 6 months, which continues up to 18 months of age. The advantage of heifers of 1/8c+1/8a+3/4kpg and 1/16c+1/16a+7/8 kpg genotypes at 6 months old was 8.1-8.6 kg, at 9 months old - 9 .2 - 12.1 kg, at 12 months old - 14.7 - 18.7 kg (Р≥ 0.95), at 15 months old - 13.9-21.4 (Р≥0.95) and at 18 months old - 12.3 - 23.2 kg (P≥0.95). As far as the group of heifers with 1/16c+1/16a+7/8kpg genotype is concerned, the average daily gain was higher than their peers in all age periods. The greatest average daily increase of 775-801 grams was noted in the period from 6 months to one year old, which is 39-73 grams more than the peers of 1/4c+1/4a+1/2kpg genotype and 27-9.0 grams more than the peers of 1/ 8c+1/8a+3/4kpg genotype. At the age of 18 months, heifers of 1/16c+1/16a+7/8kpg genotype were superior to their peers of 1/4c+1/4a+1/2kpg genotype in withers height by 3.0 cm (P≥0.999), rump height by 4.9 cm (P ≥ 0.999), chest depth by 6.8 cm (P ≥ 0.999), chest girth by 19 cm (P ≥ 0.999), oblique body length by 8.6 cm (P 0.999) , width of pin bones by 2.0 cm (P≥ 0.999), head length and forehead length (P≥ 0.999). Significant differences at the age of 18 months were revealed in withers height, oblique body length and chest girth (P≥0.99; 0.999) between heifers of 1/16c+1/16a+7/8kpg and 1/8c+1/8a+ 3/4kg genotypes.