The impact of stress-factors on viability of bulls-spermodonors at change of habitat

The influence of stress factors, caused by transportation and change of climatic environmental conditions in the bulls of Holstein breed spermogonial breeding of Canada and the Nether-lands grown up to a year at home and full-termed at Krasnoyarsk breeding farm up to 36 months of age on the indicators of the rate of growth of live weight and linear measurements of the exterior, build in-dexes in comparison with the indicators obtained from growing bulls of spermogonial domestic breeding of the Yenisei type of red-motley breed was studied. The task was from planned mating of Holstein cows and bulls to receive and bring at 11-12-month age of bulls of necessary genotypes on Krasnoyarsk breeding farm in the number of 27 heads. For control group at regional breeding farms the bulls-calves from planned mating were selected and at one-year-old age 7 bulls of necessary geno-types of the Yenisei type of red and motley breed were brought to the breeding farm. The bulls of im-port and domestic selection were delivered in No-vember, 2014 on the breeding farm; the experi-ments were made during 2015-2016. The condi-tions of keeping and feeding bull-calves of experi-mental and control groups were identical. The types of feeding bull-calves provided receiving average daily gain of live mass of 750-1000 g. Linear measurements were taken at monthly weighing bull-calves before morning feeding. The indicators of live weight growth rate, linear measurements of exterior units and constitution indexes testified that at acclimatization of bull-calves of import selection the deviations in indicators from physiological norm in comparison with bull-calves of experimental group connected with misalignment function provid-ing adaptation of the bulls and lowered adaptive abilities were revealed. Adaptive abilities of the bulls depended on pedigree accessory not much, and to greater extent they were defined by individ-ual abilities of animals and habitat conditions. Keywords: stress factor, linear growth, buildindexes, constitution, bulls-spermodonors.