ABSTRACT
Growth-promoting implants are probably the most powerful tools that cattlemen can obtain to improve production efficiency. All implants have a limited duration of activity. Compudose is probably the only implant that works for more than 100 days. Cattle that have received more than three implants have a lower marbling score and carcass quality grade is adversely affected. There has been little, if any, total gain response when more than three implants have been used. The data are too meager for recommendations to be conclusive. It is difficult to contrive a logical biological explanation for the observed deviation from continuous lifetime growth response to implanting. Implants improve performance in an entirely different way and are not a substitute for ionophores. Implants may play a special role in producing slaughter bulls because they decrease masculinity and calm down behavior—probably by restricting testicle development and testosterone production.
