Review: Androgenic, Estrogenic, and Combination Implants: Production and Meat Quality in Beef

Abstract

Literature was reviewed to determine the value of using growth implants in cattle with regard to production parameters and carcass merit. The beef industry's need to balance increased growth traits with acceptable carcass quality is of critical concern when evaluating implant strategies. Anabolic implants affect specific muscles by impacting the action of somatotropin and the rates of muscle accretion and turnover. Muscles showing the greatest response are extensor muscles associated with long bones; muscles showing little response to anabolic implants are believed to be at maximum capacity for growth. Implants may also affect the proliferation rate and (or) activation state of satellite cells. The benefits of implants to production of beef cattle have been well documented, with significant documentation of increased growth rates, ADG, and feed efficiency. Implants increase the vigor of feedlot steers by reducing the incidence of certain illnesses and, in combination with gonadotropin-releasing hormone (GnRH) immunization, replace castration for improving meat quality. Anabolic implants result in both beneficial and detrimental effects on meat quality. Implants increase ribeye area but reduce fat deposition and marbling scores. Skeletal maturity is increased by implants. The most severe quality problem from implant use is an increased incidence of dark cutters. Producers need to weigh the benefits and the disadvantages of anabolic implants for use in animal production strategies.