DEVELOPMENT OF HAIR COVERING IN YOUNG BULLS OF DIFFERENT BREEDS
DOI:
https://doi.org/10.25930/2687-1254/012.3.15.2022Keywords:
cattle breeding, young bulls, Red steppe, Simmental, Kazakh whiteheaded breed, season of the year, hair covering, weight, length, density, structure, diameterAbstract
The article presents the results of the evaluation of hair covering development by the seasons of the Red steppe young bulls (group I), Simmental (group II) and Kazakh white-headed (group III) breeds. The study of the genotype influence of young bulls and
the season of the year on the characteristics of the hair covering is due to its significant impact
on the adaptive plasticity of young animals because of its heat-protective functions in the winter season of the year. During the experimental part of the work in LLC “Kolos” in the Orenburg region, a significant decrease was noted in the mass of the hair sample from 1 cm2 of the
skin, its length, density in the summer season of the year in comparison to the winter period.
This is connected with the change of coat in spring. The obtained data show that the decrease
in the mass of the hair sample in young bulls of group I was 59.8 mg, length – 20.3 mm, density – 633 pcs; herdmates of group II – 60.3 mg, 21.2 mm, 681 pcs, respectively; young animals of group III – 60.6 mg, 21.9 mm, 849 pcs. At the same time, the leading position, in
terms of characteristics of the development of hair covering, was occupied by young bulls of
the Kazakh white-headed breed of group III. Young animals of groups I and II were inferior
to them in terms of the weight of a hair sample from 1 cm2 of skin in the winter season, respectively, by 4.2 mg (5.40%) and 2.1 mg (2.63%), length – by 4.7 mm (13.78%) and 1.8 mm
(4.86%), density by 330 pcs (22.92%) and 208 pcs (13.32%). Young bulls of the Red steppe
breed of group I were distinguished by minimal indicators of the development of the hair covering. As for the characteristics of the hair covering structure, there was multidirectional dynamics of the specific weight of different hair types by seasons. At the same time, in the
summer period, in comparison to the winter season of the year, there was a significant decrease in the under hair content with an increase in the specific weight of intermediate and
guard hair.
