Comparative Ultrastructure on Spermatogenesis of Diploidand and Triploid in Mud Loach, Misgurnus mizolepis

Ultrahistology of spermatogenic cells on spermatogenesis were analyzed from triploid males of the mud loach, Misgurnus mizolepis. All the testis of triploid males were smaller in thickness and shorter in length than those of diploid males, but the testes developmental stages in triploid males were very similar to those of diploid males. And cytological characteristics were also almost identical to each other. Also Sertoli cells with high activity were recognized at intralobuli of the testis in triploid males during the period of spermiogenesis. And then a few matured spermatozoa were observed in testis of triploid, and interstitial cells also appeared high active in interlobuli. But nucleus sizes of spermatogenic cells of triploid male according to developmental stages were larger than those of diploid overall. Especially, spermatozoa of triploid showed abnormal morphology such as two or more tail flagella, significantly larger head sizes, nucleus size, and diameter of axial filaments etc. than those from diploid.