The U.S. Food and Drug Administration has issued a warning letter to the owner of Riverview Ranch and Livestock in New York after an investigation found that the operation sold an adulterated animal for slaughter for food. The U.S. Department of Agriculture Food Safety and Inspection Service (FSIS) analyzed kidney tissue samples of a bob veal calf the ranch sold in April and found the presence of tulathromycin. FDA has not established a tolerance for residues of the antibiotic in the kidney tissue in preruminating calves. The letter states that Riverview did not use the tulathromycin as directed by its approved labeling or by a veterinarian, resulting in the illegal drug residue. In addition, the ranch failed to maintain treatment records of medicated animals that could keep potentially harmful drug residues from entering the food supply. FDA directed the ranch to “take prompt action to correct the violations” and “establish procedures to ensure that these violations do not recur. Failure to do so may result in regulatory action without further notice such as seizure and/or injunction.”