Limited survey of residual tetracyclines in tissues collected from diseased animals in Aichi Prefecture, Japan.

Tissues were collected to survey the actual conditions of tetracycline antibiotics (TCs) residues in slaughtered animals that did not pass inspection at slaughterhouses in Aichi Prefecture, Japan, because of the presence of disease symptoms. Tissues were analyzed by liquid chromatography. Among 271 samples, 49 (18.1%) were positive for oxytetracycline (OTC), 5 (1.8%) for chlortetracycline (CTC), and 5 (1.8%) for doxycycline (DC), respectively. One sample (cattle kidney) was positive for both OTC and DC. However, tetracycline was not detected in any samples. Percentage frequencies of TCs residues were 29.1% (37/127) and 15.2% (22/144) for cattle and hogs, respectively. Kidney samples showed higher incidence of TCs residues and 1.5-7 times higher residual concentrations than liver and miscellaneous samples.