Implants and thier Use in the Feedyard

Most procedures performed during the processing of feeder cattle are geared toward the prevention of problems and, therefore, economic savings. However, implanting gives a direct enhancement of performance and, therefore, economic gain. When administered properly, implants make money for the cattle feeder. It is estimated that an implant provides a return on investment anywhere from 10:1 to 20:1. That variation is due to such factors as market price, size, weight and genetic potential of the feeder animal, and type of ration. In any case, implanting feeder cattle is a sound economic practice that should be performed for financial gain. Implants act to improve feed efficiency (pounds of feed required to produce a pound of gain in body weight) and rate of gain (pounds of body weight gained per day). They are considered to be anabolic agents, enhancing protein metabolism and muscle production in the animal. Though the mechanism of action is not yet completely understood, it is felt that these agents regulate naturally produced compounds in the body to enhance growth and muscle production. In effect, they may stimulate a more consistent daily production level of these compounds, as they tend to be erratic by nature. Our industry faces a continuing challenge to educate the consumer as to the wholesomeness and safety of our product. Public concern about implanted beef plus the concept and promotion of “natural” beef-have clouded the realistic picture. These concerns are unjustified and the issue is one of public relations and education, rather than one of health. Consider these facts: 168 pounds of implanted beef contains the same amount of estrogen as one egg. Four ounces of beef contain 1.59 nanograms (1 billionth of a gram) of estrogen. An adult man averages 130,000 nanograms of estrogen production daily, and an adult woman produces an average of 480,000 nanograms of estrogen daily. The point is, not that these relatively higher levels of estrogen in eggs or humans are harmful (this is not the case), but that the level of estrogen in implanted beef is minuscule. A second or reimplant is often considered, especially in “longer day” cattle-those fed more than 100 to 150 days. Many variables have to be considered when deciding whether or not to reimplant, and there is no single answer. Consideration must be given to the type of cattle being fed (sex, breed, weight, condition on arrival, genetic potential, etc). In addition, the layout and facilities of the feedyard may or may not be conducive to reworking the cattle for reimplanting. Many reimplanted cattle weigh in excess of 800 pounds and the working facilities should be adequate to safely and effectively handle these larger cattle. Excessive stress or injuries could defeat the economic gain of the reimplant. If reimplanting is performed, consider this trip through the chute an opportunity to perform other health-related procedures. These might include a respiratory virus revaccination to abate late day respiratory pulls; a seven-way clostridial revaccination for enterotoxemia and blackleg; or a pour-on or dip for lice. Proper technique is vital to the efficacy and performance of the implant. An experienced, conscientious person “at the head” when processing cattle will make the feedyard money. Special attention to sanitation and proper placement is imperative. Currently, available implants are required to be placed subcutaneous on the dorsal surface of the ear outside the annular cartilage ring. After implantation, the implant should be easily palpable and away from any potential trim sites. Avoid any blood vessels or previous implants and ear-tag first so as not to disrupt an implant site. We encourage processing crews to use sharp implant needles, change them when dull, and lay the needle on a disinfectant-soaked sponge between usages. Do not dip the needle in a liquid disinfectant as this moistens the inner core, causing partial dissolution and “gumming” of implants. It is helpful to run occasional checks to evaluate implant technique. This may be done either at initial processing, when doctoring cattle, at reimplantation, or on a post mortem check at an abattoir. Crushing or bunching implants may result in over-absorption and decreased duration of efficacy. Abscessed implants, walled-off implants, and implants placed in the cartilage of the ear may result in under-absorption and decreased efficacy. The buller syndrome sometimes is tied to implants. Though there may be some relationship, this problem probably is more related to technique, rather than brand of implant used. In our experience, the buller syndrome is a multi-factorial problem—more tied to season of the year, weather patterns, type, age and breed of cattle, bunk management and pen space per head.       Growth Promotants       Classification Ingredients            Product      Category I        Active Days = < 70 Low Estrogen Equivalent            Ralgro 36 mg Zeranol            Synovex C 10 mg Estradiol Benzoate, 100 mg Progesterone            Component E-C 10 mg Estradiol Benzoate, 100 mg Progesterone            Revalor G 8 mg Estradiol, 40 mg TBA            Synovex T40 8mg Estradiol, 40 mg TBA            Component TEG 8 mg Estradiol, 40 mg TBA      Category II     Active Days = >70, <90 Strong Estrogen Equivalent            Synovex S 20 mg Estradiol Benzoate, 200 mg Progesterone            Synovex H 20 mg Estradiol Benzoate, 200 mg Testosterone Propionate            Component E-S 20 mg Estradiol Benzoate, 200 mg Progesterone            Component E-H 20 mg Estradiol Benzoate, 200 mg Testosterone Propionate            Ralgro Magnum 72 mg Zernol            Compudose 25.7 mg Estradiol 17-B            Encore 43.9 mg Estradiol 17-B      Category III Active Days = > 90, < 110        Low TBA Equivalent            Revalor S 24 mg Estradiol, 120 mg TBA            Synovex T120 24 mg Estradiol, 120 mg TBA