Method and Timing of Castration Influences Performance of Bull Calves
C.A. Lents, F.J. White, L.N. Floyd, R.P. Wettemann, and D.L. Gay
Oklahoma State University
In the United States, more than 17 million bulls between 1 d and 1 y of age are castrated annually. However, many producers still do not castrate even though calves marketed at weaning as steers have a $3.56/cwt advantage compared with bulls (Smith et al., 2000). Bulls that are castrated and given an estrogenic growth stimulant have similar weight gain compared with bulls (Bagley et al., 1989), yet producers often cite fear of reduced weaning weights as a reason for not castrating. Castration decreases aggressive behavior and increases carcass quality (Seideman et al., 1982). Bulls that were castrated at weaning had decreased weight gains compared with bulls castrated at 150 lb (Worrell et al., 1987; Chase et al., 1995), and castration of bulls that are older and heavier causes stress (Fisher et al., 1996). Castration of bulls 6 to 9 mo of age decreased weight gain by 50% compared with intact controls (Faulkner et al., 1992; ZoBell et al., 1993). Bulls can be castrated by surgical removal of the testes, banding of the scrotum with rubber bands, or crushing of the testicular chords with a burdizzo. Minimal information is available on the effect of method or timing of castration on performance.