Contagem celular e rendimento da espermatogênese em ovinos Santa Inês e mestiços Santa Inês e Dorper / Cell count and efficiency of spermatogenesis in ovine Santa Ines and mongrel Santa Inês and Dorper

ABSTRACT

With the objective to evaluate the efficiency spermatogenesis between sheep breeds, sixteen testicles,eight sheep, four belonging to the race Santa Ines and four of mongrel of Santa Inês and Dorper. After thecastration of animals, we obtained the gonadosomatic index. Generally the average diameter, relative frequencyof the stages in the life cycle of the seminiferous epithelium, yield of spermatogenesis, yield, meioticspermatogenic yield and efficiency of Sertoli cells. There were no significant differences between the races onthe phases of the cycle of the seminiferous epithelium, number of spermatids rounded, Sertoli cells, mitotic rateand effectiveness of Sertoli cells. However, the animals mongrel were higher as the population ofspermatogonia, primary spermatocytes in paquíteno and in pre-leptóteno/leptóteno, yield and meioticspermatogenic yield line. The study showed that animals mongrel of sheep breeds Santa Inês and Dorperpresented higher reproductive potential when compared with pure lambs of Santa Ines.