Oxytetracycline Residues in Tissue, Organs, and Eggs of Poultry Fed Supplemented Rations

Oxytetracycline was fed continuously to broilers at 25 to 200 g/ton from the age of 1 day to 11 weeks. Residues in the muscle tissue at 11 weeks ranged from trace quantities at 25 g/ton to 0.20 μg/g at 200 g/ton; liver residues ranged from not detectable to 0.29 μg/g at 200 g/ton; kidney levels ranged from 0.09 to 0.78 μg/g at 200 g/ton. Tissue, blood, liver, kidney, and intestinal contents were negative 24 hr after withdrawal from the drug. Cooking destroyed all residues in muscle tissue but livers retained 50% of the uncooked levels. Eggs from hens fed up to 400 g/ton contained no measurable residues.