ON THE INHERITANCE OF A FHENOTYPIC TRAITS DY DAUGHTERS OF YAK BULLS (POEPHAGUS GRUNNIENS L.) OF DESIRED TYPE OF OKINSKY BREED
The analysis of population structure of Oka yaks on phenotypic traits of colour and having a horn is conducted. Oka yaks populations are noted by more broad spectrum of coat colour and they are dominated by animals of black and black-motley colour (59.8 %), which was the rationale for the characteristics of yaks of desired type for creating the breed. Wild yaks are horned and black coloured. When creating a breed of yak the task was to use yak bulls of desired type – hornless black coloured and black coloured with a white spot on forehead. In a herd where evaluation by yak bulls offspring was held, hornless females of black colour was 22,4 %, and black with white markings (hair) color was 44,8 %. Daughters of yak bull Ilm 4252 revealed black hornless 15 (83,2 %) and black hornless with white spot on the forehead 1 (5,6 %). The offspring of a yak bull Raven 4231 revealed hornless black with a white mark on the forehead 14 (56,0 %). The studies support the hypothesis that the choice of the desired type of animals is home yak Poephagus grunniens L. Okinsky breed.