Abstract
Ricinus communis L. of Euphorbiaceae family is a widespread plant in tropical regions. It is used in traditional medicines as an anti- fertility agent in India and different parts of the world. The ether soluble portion of the methanol extract of R. communis var minor possesses anti-implantation, anti - conceptive and estrogenic activity in rats and mice when administered subcutaneously.The study was conducted on 10 local breed male rabbits, 1-2 years old, of 1-2 kg body weight. The animals were divided into two groups, control non – treated group and treated group in which animals were treated with single daily dose of 50 mg /kg b. wt. P.O. of decorticated and defatted castor seeds (DDCS) for 14 days. 28th day post treatment, animals were anesthetized by diethyl ether, sacrificed, abdominal cavity was open. The sexual organ (testes, epididymis, prostate and seminal vesical) weighed. In addition to take a biopsy from each one for histopathological changes. The study also included clinical and hematological parameters, in addition to sperm counts and the changes in sperm morphology.Body weight, body temperature increased significantly in treated males. While in non- treated group there were no significant changes. Respiratory rates and heart rate were none significantly changed in treated and non- treated males.Bleeding time none significantly increased in treated males, but increased significantly in none treated males. Clotting times decreased none significantly in treated and non- treated males. The blood parameters including, total erythrocytes count, hemoglobin concentration, PCV% , MCV, MCH, MCHC, total leucocyte and differential leucocyte counts were either increased or decreased none significantly in both groups. The results revealed that the effects of exposure to extract of ricin for 14 days on reproductive efficiency of rabbits, exhibited Significant decrease in weights of testes, epididymis, tails, heads of epididymis, seminal vesicles and prostate in treated males in comparison with those of non- treated males. While the body of epididymis did not show a significant changes.Significant decrease in live sperm numbers, number of sperms in epididymal head, in addition to deformities in high numbers of sperm, including enlarged or small sperms. breaks head, and its detachment, presence of two heads in one sperm, bifurcation of tail and its breaking, sperm coiling in samples from treated males in comparison with those from non-treated males.Histological changes were hyperplasia of lining epithelial cells and vacuolar degenerative changes, loss of spermatogenesis, and spermatocytes necrosis in those from treated males.

Key words: Reproductive activity, Rabbit, Ricinus communis