Developmental study of testis in local Awasi sheep foetuses during first and second trimester of gestation
Objective: The present work was designed to investigate the characteristic of morphohistological development of testes in Iraqi Awassi sheep foetuses.
Design: A description of the prenatal and histomorphological developmental of the testes in the Awassi sheep prenatally
Material and methods: The current study was performed on 12 sheep's foetuses collected from health female's pregnant sheep to describe the histomorphological changes of testes. The foetuses represented two gestational stages: (50-55 day) and (72-77 day).
Results: At 50-55 day of gestational age, tests were irregular oval like shape located in abdominal cavity. Histologically, testis wall comprised of germinal epithelium layer that consist of simple squamous epithelium tissue with a large number of mesenchymal cells, the tunica albuginea of testis appeared relatively clear and did not differentiate into tunica fibrosa and vasclosa. Also, the current study had proven present of sex cords and blood vessels with anlage of large cell called pre-sertoli cells. At 72-77 day of gestational age, the testis was found to be irregular oval and elongated in shape and located in the abdominal cavity. Histologically, the testicles ware surrounded by germinal epithelium composed of simple cuboidal cells distributed in patches of simple squamous cells, the tunica albuginea was divided into tunica fibrosa and vasculosa, while the sex cord appeared more developed and slightly concave located near the germinal epithelium margin
Conclusions: This study revealed that the testes appeared small and not well developed histomorphologically at prenatal stage.