October and November are typical months for calf weaning, pregnancy checking of cows, and cow culling. On very rare occasions violative residues of pharmaceutical products have been found in carcass tissues of cull beef cows. Violations of drug residue regulations can result in expensive fines (or even worse, jail time) for the rancher and a “black-eye” for the entire beef industry.
It is vital that cow calf producers have a close working relationship with a large animal veterinarian in their area. If a cow has an infection or disease that must be treated, her owner should closely follow the veterinarian's directions, and also read the label of the product used. Most of these medications will require that the producer keep the treated animal for the label-directed withdrawal time. The Beef Quality Assurance Manual usually contain the following discussion of medication withdrawal times.
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