Original Article
Korean J Parasitol. 1976 Dec;14(2):123-132. English.
Published online Mar 20, 1994.  http://dx.doi.org/10.3347/kjp.1976.14.2.123
Copyright © 1976 by The Korean Society for Parasitology
A morphological study on spermatogenesis in the liver fluke, Clonorchis sinensis
Kye-Heon Jeong,Han-Jong Rim,He-Young Yang,Woo-Kap Kim and Chang-Whan Kim
Department of Parasitology and Institute for Tropical Endemic Diseases, College of Medicine, Korea University, Korea.
Department of Biology, Korea University, Korea.
Abstract

Spermatogenesis in liver flukes, C. sinensis, was investigated by using light and electron microscopes.

The epithelium of the testis was composed of a basement membrane, numerous lamellae protuded from the membrance and large number of spermatogonia supported by the lamellae.

The lumen of the testis was filled with numerous 8, 16 and 32-cell groups representing primary spermatocytes, secondary spermatocytes and spermatids respectively. None of cell groups with over 32 or under 8 cells was noticed.

The process of spermatogenesis is presumably as follows;

A cell group of 8 spermatogonia, attached together by a cytophore, is separated from the testis epithelium during the growth period, thus becoming primary spermatocytes. The primary spermatocytes divide to form a cell group of 16 secondary spermatocytes giving rise to a cell group of 32 spermatids through meiotic germ cell division. The spermatids begin to undergo a spermiogenesis.

The newly formed sperms remain attached together in the lumen for a while before migrating through the vasa efferentia.

Figures


Figs. 1-8
Light micrographs of germ cells,

1. Eight primary spermatocytes centrally connected by a cytophore.

2. Primary spermatocytes undergoing a meiosis.

3. Secondary spermatocytes composed of 16 cells.

4. Spermatids composed of 32 cells.

5. Spermatids undergoing a spermiogenesis. Each cell protrudes a tail(F).

6. Spermatids with elongated nuclei(N).

7. Late spermatids with elongated and bent nuclei.

8. Mature spermatozoa from seminal receptacle.



Figs. 9-10
Electron micrographs.

9. Testis epithelium composed of basement membrane(Bm), lamella(Lm), and spermatogonia(Sg).

10. Several secondary spermatocytes(St) containing centrioles (C) are connected by a cytophore(Cp).



Figs. 11-12
Electron micrographs.

11. Spermatids undergoing a spermiogenesis are still connected each other.

12. Lumen of the testis including a Sertoli cell(Sc), several spermatcytes(St) and numerous differentiation spermatozoa(Sp) in various stages.



Figs. 13-14
Electron micrographs.

13. Numerous cell groups undergoing a spermiogenesis.

14. A spermatid has a tail including two sets of filaments (F) and two rootlets(Rt).


Abbreviations
Bmbasement membrane
Ccentriole
Cpcytophore
Cycytoplasm
Ffilament
GGolgi complex
Hsperm head
Lmlamella
Lulumen of testis
Mmitochondria
Nnucleus
Rtrootlet
ScSertoli cell
Sdspermatid
Sgspermatogonia
Spspermatozoa
Stspermatocyte
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