Effect of Ambilhar (niridazole) on spermatogenesis in guinea-pigs

Niridazole (Ambilhar), a new antibilharzial drug was fed for 5 days to 20 male guinea pigs at 50 mg/kg while testicular and epididymal biopsies were examined histologically for 10 weeks. Only 10 animals survived the treatment. On the 5th day sperm numbers were reduced in testis tubules. On Day 8 variations in tubule size and in degrees of inhibition of spermatogenesis were at their maximum. Some tubules had recovered spermatogenesis at 15 days, and all had at 3 weeks. Guinea pigs are more sensitive to niridazole than are rats.