Abstract   

    The effect of an intra testicular injection of neutral buffered formalin solution on seminiferous tubules was studied in Awassi lambs. Animals injected intra testicularly with 1 ml of 10% formalin in the right testes (treated group: n = 10) showed a decrease in size (p <0.01) and weights (p < 0.05) of the testes with- or without- tunica vaginalis parietalis, one month after treatment compared to the control group (normal saline; n = 4). Light microscopic examination showed that the number of seminiferous tubules in each field was higher (p <0.05) in the testis of treated group. In the treated testes, seminiferous tubules were more prominent owing to the presence of large quantity of connective tissue. An increase in vascularity and connective tissue mass with the presence of limited number of macrophages in interstitial tissue was also observed. In conclusion, formalin causes reduction in size and weight of testes by destroying seminiferous tubules. Thus formalin possesses the potential to be considered for chemical castration.   

Key words: Testis, formalin injection, lambs