2001 Volume 72 Issue 2 Pages 89-96
Records and pedigree information of Japanese Black Cattle collected from performance testing and progeny testing in Miyagi prefecture were used to estimate heritabilities (h2) and genetic correlations (rG) for the traits for meat productivity using a two-trait animal model by Gibbs sampling method. The estimates of h2 in growth traits in performance testing were at a low level (h2<0.3) for daily gain (DG) and at a medium level (0.3=<h2<0.6) for initial and final weights. While the h2 estimate of concentrate feed intake was at a medium level, those of roughage intake and total digestible nutrient (TDN) conversion ratio were at low levels. Growth traits had positive rG estimate with food intake and this suggests that attention should be paid to feed intake performances for achieving genetically improved growth traits. The h2 estimates of carcass weight, the old beef marbling standard (BMS) (BMS1), the new BMS (BMS2) and rib thickness were high (h2>=0.6), and those of initial body weight, DG and yield estimates were at medium levels, meanwhile, the h2 of rib eye area and subcutaneous fat thickness were estimated to be low. There were negative rG estimates among DG and BMS 1 or BMS2. The rG estimate (+0.687) between BMS1 and BMS2 was not as high as initially expected and this might be attributed to two different evaluating methods of meat marbling.
