tailieunhanh - Báo cáo sinh học: "Impact of two myostatin (MSTN) mutations on weight gain and lamb carcass classification in Norwegian White Sheep (Ovis aries)"

Tuyển tập các báo cáo nghiên cứu về sinh học được đăng trên tạp chí sinh học quốc tế đề tài: Impact of two myostatin (MSTN) mutations on weight gain and lamb carcass classification in Norwegian White Sheep (Ovis aries) | Boman et al. Genetics Selection Evolution 2010 42 4 http content 42 1 4 Ge n et i cs Selection Evolution RESEARCH Open Access Impact of two myostatin MSTN mutations on weight gain and lamb carcass classification in Norwegian White Sheep Ovis aries Inger A Boman1 2 Gunnar Klemetsdal1 Ola Nafstad3 Thor Blichfeldt2 Dag I Vage4 Abstract Background Our aim was to estimate the effect of two myostatin MSTN mutations in Norwegian White Sheep one of which is close to fixation in the Texel breed. Methods The impact of two known MSTN mutations was examined in a field experiment with Norwegian White Sheep. The joint effect of the two MSTN mutations on live weight gain and weaning weight was studied on 644 lambs. Carcass weight gain from birth to slaughter carcass weight carcass conformation and carcass fat classes were calculated in a subset of 508 lambs. All analyses were carried out with a univariate linear animal model. Results The most significant impact of both mutations was on conformation and fat classes. The largest difference between the genotype groups was between the wild type for both mutations and the homozygotes for the mutation. Compared to the wild types these mutants obtained a conformation score classes higher and a fat score classes lower both on a 15-point scale. Conclusions Both mutations reduced fatness and increased muscle mass although the effect of the frameshift mutation was more important as compared to the 3 -UTR mutation A . Lambs homozygous for the mutation grew more slowly than those with other MSTN genotypes but had the least fat and the largest muscle mass. Only showed dominance effects. Background In Norwegian White Sheep NWS two myostatin MSTN mutations affecting conformation and fat classes are segregating the 3 -UTR mutation creating an illegitimate microRNA site A that was identified in Texel sheep 1 and a frameshift mutation explained by a deletion of one .