Abstract
A comparison was made between the beef carcasses of Japanese Black bull progeny produced by either artificial insemination (AI) or the in vitro fertilization technique (IVP). The calves produced by AI were raised following a field progeny test procedure in Japanese Black bulls, and the embryos produced by IVP were transferred to Holstein cows for the production of progeny. The progeny performance test was performed on two bulls. For bull A, 19 calves (AI: 10 calves, IVP: 9 calves) and for bull B, 20 calves (AI: 9 calves, IVP: 11 calves) were used. Analysis of variance was performed using the two breeding techniques and the bull×breeding technique interaction as the source of variance in order to evaluate the factors that affect dressed carcass performance. Significant differences (P⟨0.05) in carcass weight and marbling were observed between the bulls, which are the primary factors affecting bull performance. No interaction was found regarding these two traits, rib eye and rib thickness between bulls and breeding techniques. These results suggest the possibility of a meat-production performance test using a group of siblings, half of which have been produced by IVP.
