Various preventive and therapeutic medicines may be used for disease management in show market livestock and poultry. These include vaccines and bacterins, antibiotics and antibacterials, parasiticides, and corticosteroids. Exhibitors of show animals must ensure that carcasses are free of violative and illegal residues of drugs, chemicals, and feed additives. Therefore, only substances approved for the animal species being treated should be used, and these must be administered prudently. Compounds such as tranquilizers, local and systemic anesthetics, diuretics, caffeine, and alcohol are not approved for show market animals.

Withdrawal Times
Approved substances generally have established withdrawal times. These are printed on the product label, package, package insert, or feed tag. The withdrawal time is the length of time required for the substance to be eliminated from the animal’s body or to be reduced to a safe (tolerance) level prior to slaughter. The drug, chemical, or feed additive is to be withdrawn for the number of days listed on the label before the animal is slaughtered. If there is no withdrawal time on a product label, it means the substance either is safe or is reduced to a safe level in the animal within 24 hours.

Disease Prevention
After the risk of exposure to specific diseases has been evaluated, a preventive program may be established. Animals may be given vaccines or bacterins which stimulate them to build immunity to specific diseases. Vaccination is not to be done within the published withdrawal time prior to slaughter. Vaccinated food animals are not to be slaughtered until the withdrawal time has ended.

Approved antibiotics, antibacterials, and parasiticides may be used to prevent diseases for which there are no vaccines or bacterins. These substances can be administered continuously in the animal’s feed or water. But medicated feed and water are not to be fed within the products’ published withdrawal times prior to slaughter. Nor are medicated food animals to be slaughtered until the withdrawal time has expired.

Disease Treatment
When a medical condition is diagnosed, a therapeutic or treatment program may be established which makes use of approved antibiotics, antibacterials, dewormers, coccidiostats, and insecticides. These substances are not to be administered within their withdrawal times prior to slaughter. Treated food animals are not to be slaughtered until the withdrawal time has expired.

Corticosteriods (cortisones), which are sometimes used to treat musculoskeletal conditions, are prescription or restricted (Rx) products. Restricted products can be used only by or on the order of a licensed veterinarian. The veterinarian prescribing the medication will give instructions as to the withdrawal time. These instructions are to be followed precisely.

Testing
The Food Safety and Inspection Service (FSIS) collects samples (urine, kidney, liver, fat, and muscle) of show animal carcasses at slaughter. These samples are tested for residues of approved and unapproved substances. Residues of approved substances must be below the safe level, and there must be no residues of unapproved substances. Otherwise the carcass will be condemned. If the carcass is found to contain violative residues, the animal may be disqualified from the livestock show.

In addition to testing at slaughter, livestock show officials may collect urine and blood samples at the show grounds for submission to laboratory testing. If the livestock show rules require that market animals not be within the withdrawal time of any drug, chemical, or feed additive at the time of weigh-in, a violative sample may cause an animal to be disqualified.

Illegal Usages
It is illegal for an exhibitor to administer a drug, chemical, or feed additive by a route, at a dosage, for a condition, or to a food animal species not indicated on the product’s label. Such practices can alter the determined withdrawal time and can cause violative residues at slaughter. Use of any unapproved substance in a food animal species is illegal, even if the substance is approved for a different species. This is because safety, efficacy, and withdrawal time data have not been established for species not listed on the label, and carcasses may become adulterated with residues.

An exhibitor should follow all label and package insert instructions for any drug, chemical, or feed additive used to prevent or treat disease or injury. This will ensure that consumers will receive safe, high-quality animal food products. Also, the exhibitor should consult with a veterinarian, county Extension agent, and agricultural science teacher about livestock show rules and federal laws regarding residue avoidance and food safety programs. Medication is to be used only when absolutely necessary, and never as a substitute for proper care, handling, and management of show market animals.