Effects on performance and meat quality of Holstein bulls fed high concentrate diets without implants following immunological castration

The objective of this study was to evaluate the effect of the GnRH vaccine on the performance and meat quality of Holstein bulls fed high concentrate diets. A total of 493 approximately 7 month old bulls (initial BW 298 ± 1.2 kg) were allocated into 3 treatment groups, intact bulls (n = 164), animals surgically castrated at 15 to 17 d of the study (n = 164), and animals vaccinated on 0 and 28 d of the study with the GnRH vaccine (n = 165). Animals were slaughtered between 131 and 133 d and carcass quality was evaluated. Hot carcass weight, dressing percentage, fat classification and meat quality parameters did not differ significantly between surgically castrated and vaccinated animals but differed (P < 0.05) from intact bulls. Carcass classification, pH at 26 h, and fat color were not affected by treatment.