Ivermectin considered natural fermentation product derived from soil bacterium streptomyces avermitis and it
is abroad spectrum insecticide, acaricide and anthelimintic. This studies carried out in order to investigate the
histopathological effects of therapeutic and double therapeutic dose of ivermectin on mature male rabbits as
well as effect of therapeutic dose of same drug on pregnant female rabbits. Forty mature rabbits were used in
this study (30 males and 10 pregnant female). Male rabbits received therapeutic and double therapeutic doses
of ivermectin, while female rabbits received therapeutic dose. The histopathological results revealed mild to
moderate reversible degenerative changes in examined organs of male rabbits received ivermectin weekly for
4weeks meanwhile, this degeneration become more severe and extended to complete necrosis in some organs
after longer period and higher doses of ivermectin administration. As well as, pregnant females suffered from
abortion in some cases with fetal death. We concluded that ivermectin has adverse effect on male rabbits that
received either therapeutic or double therapeutic doses that varied from mild degenerative changes to complete
necrosis of spermatogenic cells with complete absence of sperms. Meanwhile, female genital system was
severely affected that showing severe degeneration and hemorrhage in uterus as well as atritic follicles and
degenerated ova in ovaries. So, caution must be considered for ivermectin administration especially during
breeding season and for pregnant females.