Adaptation abilities of imported bulls-sperm donors of Holstein breed of red-motley population in the JSC “Krasnoyarsk agricultural“

The effectiveness of reproduction depends on adaptive capacity of animal body, having specific and individual particular qualities of adaptability to different environmental conditions. Indicator of adaptive capacity can be qualitative and quantita-tive indicators of sperm production of bulls-producers and the duration of their use in breeding enterprises. To establish the period of adaptation to new service conditions of imported bulls we exam-ined the basic indicators of their sperm. The sperm production of Holstein bulls of red-motley popula-tion of Dutch breeding imported in the JSC “Kras-noyarsk Agricultural Breeding Establishment” (V. Solontsy, Krasnoyarsk Region) was analyzed. Quantitative and qualitative indicators of sperm were evaluated, the proportion of abnormal forms of spermatozoa in winter and spring seasons was determined, the sizes of spermatozoa have been established, the ability of sperm to freezing have been estimated. Conducted researches showed that at the beginning of operation the main indica-tors of sperm production were at low level. Then they gradually increased and by sixth month reached high values. The main groups of atypical forms of spermatozoa were identified: the defor-mation of tail, twisted tails, torn off heads. The analysis of spermatozoa on the ability to freeze showed that by the end of adaptation period the spermatozoa of bulls well tolerated cryopreserva-tion. Holstein bulls-producers of red-motley popula-tion of Dutch breeding well tolerated changes in conditions of keeping and operation. All bulls adapted to new conditions within six months.