EN
Quinolone-induced arthropathy has been observed after a single very large dose, or after several moderately large doses in juvenile animals of multiple species. The purpose of the present study was to determine whether long-term treatment with therapeutic doses of enrofloxacin has a detrimental effect on chicken articular cartilage. 21-day-old broiler chickens were treated orally with 10 mg/kg/day of enrofloxacin for 10, 20 and 35 days. 24 hours after the last dose, the animals were killed and the femoral head with condyles and tibial condyles were subjected to a gross and histopathological investigation. The necropsy did not reveal macroscopic visible pathological changes in the articular cartilage surface, as well as in soft tissues surrounding joints in any of the animals from this study. Also, light microscopy evaluation did not show significant histopathological changes in any of the specimens from either experimental and control animals. In conclusion, our results indicate that treatment with a therapeutic dose of enrofloxacin for a period exceeding the recommended duration of therapy does not cause arthropathy in growing chickens. Moreover, the results obtained seem to indicate that chondrotoxicity of quinolones does not have a cumulative nature.