Мінливість показників продуктивності та ступінь фенотипового домінування у кролів при схрещуванні різних порід

Abstract

Goal. To investigate the level of variability of productivity indicators and the degree of phenotypic dominance in rabbits when crossing breeds of different directions of productivity. Methods. The study was conducted based on the rabbit farm of the Cherkasy Research Station of Bioresources of NAAS on the population of rabbits of the breed Poltavske sriblo with the use of breeders of Radianska chinchilla, Novozelandska bila, and their descendants. Results. The degree of variability of selection traits in rabbits at a combination of breeds of a different direction of productivity is determined. A probable predominance was inserted by the length of the body in young rabbits obtained by crossing rabbits of Radianska chinchilla and Poltavske sriblo breeds (by 7 cm, P>0.999). According to the rest of the indicators (breast circumference, live weight at different ages, lumbar width), animals obtained as a result of crossing males of Novozelandska bila breed and females of Poltavske sriblo (P0.99). The color of the fur in both crosses had a wild form of “agouti”. The presence of a high degree of inheritance by selection traits in the offspring: body length (h2=0.46–0.70, P>0.999), lumbar width (h2=0.48–0.56, P>0.999) and for young animals rabbits meat productivity, live weight at the age of 120 days (h2=0.62, P>0.999). The share of the influence of the breed on the manifestation of the trait in the offspring varied in the range of 0.01–0.49, the probable influence of the breeder was determined by the length of the body and the hardness index (ηx2=0.32 and 0.49, P>0.999), which indicates dominance on this basis of the breed of meat direction of productivity. Conclusions. At crossing breeds of rabbits of the combined and meat directions of selection the maximum level of heredity of traits is revealed on an indicator of the length of a body: at breeds of the combined direction the phenotypic correlation between traits of mothers and descendants is positive, and at crossing with breeders of a meat direction of productivity — negative, i.e. this indicator decreased. There is also a high degree of inheritance of live weight in the descendants for the combination of rabbits Poltavske sriblo with breeders of Nevozelandska bila breed. In both variants of crossing, the descendants lose the characteristic fur color of the parent forms, which indicates the recessive nature of this trait. The maximum influence of the male breed was on the indicator of body length and the hardness index of the descendants.