Testosterone and the incidence of boar taint: Effects of testosterone or testosterone propionate on the incidence of boar taint in implanted barrows.

Boars, barrows and barrows implanted with testosterone or testosterone propionate via polydimethylsiloxane (Silastic) capsules were placed on test in individual pens at 10 weeks of age. Each animal was slaughtered at 110 kg and evaluated for growth rate, efficiency of feed utilization, carcass merit and the incidence of objectionable odors (boar taint). Five capsules of testosterone or testosterone propionate were used in barrows since they substantially elevated concentrations of serum testosterone, decreased serum LH and stimulated weights of the accessory sex glands. Large variations within and between litters of pigs were found for performance and carcass traits; thus, the influences of castration and testosterone replacement therapy on these traits were inconclusive. In contrast, the effects of castration and hormone treatment on the incidence of boar taint were more definitive. The incidence of boar taint was relatively high in boars, according to a consumer taste panel. This characteristic odor was appreciably lower in barrows and was not reinstated with either testosterone or testosterone propionate implants. These results suggest that testosterone is not itself responsible for boar taint and that 5α-androstenone, the pheromone most closely associated with boar taint, is not produced by peripheral metabolism of testosterone. Additional studies are warranted to provide insight into the regulation of testicular steroid secretion in the boar and the contribution of these steroids to boar taint and protein anabolism.