Abstract
The aim of this study was to investigate the testicular and genotoxic effects of chlorpyrifos, an organophosphate insecticide,
in adult male Japanese quail. For this purpose a total of 75 sexually mature birds were procured and randomly kept in five
equal groups. Chlorpyrifos was given @ 0, 6, 8, 10 and 12 mg/kg BW orally for 36 days to experimental birds present in all
groups (A-E). Adverse effects such as gasping, depression, watery droppings, decreased foam production, tremors and less
frequency of mounting with pen mates were evident in a dose-dependent manner. Chlorpyrifos decreased feed intake, body
weight and relative weight of testes, liver and kidneys as compared to control birds. Histopathological examination of
seminiferous tubules of testes at higher concentration of chlorpyrifos (10 and 12 mg/kg BW) revealed less number of
spermatogenic cell layers, increased number of degenerated spermatozoa and multinucleated giant cells. Furthermore,
histopathological examination of liver tissues indicated extensive cytoplasmic vacuolation. Moreover, mild to moderate
congestion with sporadic tubular epithelial cell necrosis was observed in kidneys. Significantly increased comet tail length
confirmed DNA damage at higher concentration of chlorpyrifos in isolated lymphocyte and bone marrow cells. It was
concluded that chlorpyrifos at 10 and 12 mg/kg BW rendered various clinical, pathological alterations in internal organs and
was also involved in genotoxicity.