Evaluation of the toxic potentials of cypermethrin pesticide on some reproductive and fertility parameters in the male rats

Adult male Sprague-Dawley rats were exposed to tap water containing 0, 8,57 1, 17,143, or 34,286 ppm cypermethrin for 12 weeks. Based on water consumpt ion per animal per day the rats received 13.15, 18.93, and 39.66 mg cyperme thrin. respectively. Fertility was significantly reduced in male rats inges ting cypermethrin at a concentration of 13.15 and 18.93 mg in that the numb er of females impregnated by them was significantly reduced. The number of implantation sites was significantly reduced in females mated with males th at had ingested cypermethrin at a concentration of 39.66 mg. A significant reduction in the number of viable fetuses was observed in females impregnat ed by the exposed males at all three doses of cypermethrin. The body weight gain was significantly lower in the treated males. Ingestion of cypermethr in at a concentration of 18.93 or 39.66 mg per day resulted in a significan t increase in the weights of testes and seminal vesicles. Preputial gland w eights were increased at all three concentrations of cypermethrin. Epididym al and testicular sperm counts as well as daily sperm production were signi ficantly decreased in exposed males. The serum levels of testosterone. foll icle-stimulating hormone and luteinizing hormone were significantly reduced in males exposed to 39.66 mg per day. Ingestion of cypermethrin at 18.93 a nd 39.66 mg/animal/day also resulted in a significant decrease in the perim eter and number of cell layers of the seminiferous tubules. The testes of t reated animals were infiltrated with congested blood vessels with marked he morrhage and a significant accumulation of connective tissue surrounding th e seminiferous tubules, which contained a large number of immature spermati ds. These results clearly demonstrate the adverse effects of cypermethrin p esticide on fertility and reproduction in male rats.