Survey of Residual Tetracyclines in Tissues Collected from Slaughtered Animals in Aichi Prefecture, Japan, 1985-1996

Abstract

Tissues were collected to survey the incidence of tetracycline antibiotics (TCs) residues in slaughtered animals that did not pass inspection at slaughterhouses in Aichi Prefecture, Japan, April, 1985-March, 1996, because of disease symptoms. Tissues were analyzed by liquid chromatography. Among 218 animals (85 cattle and 133 hogs), 79 (30.9%) were positive for TCs, including 43 (19.7%) for oxytetracycline (OTC), 3 (1.4%) for tetracycline, 28 (12.8%) for chlortetracycline, and 1 (0.5%) for doxycycline (DC). One sample (cattle kidney) was positive for both OTC and DC. Cattle and hog samples collected in 1991-1995 showed significantly higher incidence of TC and CTC residues than those in 1985-1986 (X2-test), respectively. Kidney samples showed higher incidence of TCs residues and 3-4 times higher residual concentrations than liver samples.