THE CYCLE EVENT OF SPERMATOGENESIS AND SPERMIOGENESIS IN THE TESTES OF INDIGENOUS DUCK (ANAS PLATYRHYNCHOS)
2014
Kadhem | A.Z
Morphologically,the testes of adult duck was suspended by mesorchium with the roof of the the abdominal cavity. The testes appear as elongated bean shaped and situated asymmetrically. The mean average of the testis was 1,48 cm in length, 0.47cm in width, and 1.54gm in weight. Histologically, each testis was covered by a connective tissue capsule.The stroma of the testis posses no mediastinum. Leydic cells were commonly found in groups within the connective tissue which filled the spaces between the seminiferous tubules. Germ cells and Sertoli cells constituent the main component of the seminiferous epithelium. There were type A-spermatogonia, type I-spermatogonia, and type B-spermatogonia. Type B-spermatogonia passes through proleptoten, leptotene, zygotene, pachytene, diplotene, and diakineses. The primary spermatocytes give rise to secondary spermatocytes. These latter cells enter the second meiotic division to form the spermatids which undergo through thirteenth stages to form the sperms.
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