Abstract
To investigate the potential subchronic toxicity of cyadox, groups of 15 male and 15 female Wistar rats were fed with diets containing cyadox (0, 50, 150 or 2500
mg/kg) or olaquindox (150
mg/kg), approximately equivalent to cyadox 5, 15, 250 or olaquindox 15
mg/kg
b.w./day, for 13 weeks. Five rats/sex/group were sacrificed on days 30, 60 and 90. No test-material-related changes were seen in mortality, clinical signs, hematology, clinical chemistry, organ weight data and macroscopic examinations. Except that body weights of both sexes of the 2500
mg/kg cyadox group were significantly lower than controls beginning after the second week of treatment. Body weights of females of 150
mg/kg olaquindox group were significantly lower than those of the control group at weeks 3 and 4. Other groups were unaffected by treatments. Histopathological observations revealed that 2500
mg/kg cyadox or 150
mg/kg olaquindox induced swelling and fatty degeneration of the hepatocytes and proximal renal tubular epithelial cells. It was for the first time that changes were found in the liver and kidneys of rats fed 2500
mg/kg cyadox. The no-observed-adverse-effect level (NOAEL) of cyadox for rats was estimated to be 150
mg/kg dietary dose level.
