Morphological and histochemical studies on the development of testis and spermatogenesis in the ruminal trematode of sheep, Paramphistomum cervi (Digenea: Paramphistomatidae)
Gupta, B.C.; Parshad, V.R.; Guraya, S.S.
Folia Parasitologica 33(2): 131-144
1986
ISSN/ISBN: 0015-5683 PMID: 3721355 Document Number: 282565
Morphological and histochemical changes accompanying testicular development and spermatogenesis are described in P. cervi in sheep. Small testes of 4-week-old worms contain a few primordial germ cells. Spermatogonial cells first appear at week 6 and increase in number by week 10, when the testes become large and follicular. Mature spermatozoa develop in 16-week-old worms. The general pattern of spermatogensis is typical, i.e. a single spermatogonium gives rise to 32 spermatozoa. Cytophore is formed at the secondary spermatogonial stage. Various spermatogenic stages contain proteins, glycogen and phospholipids, however, the amount of phospholipids decreases as maturation proceeds. Mature spermatozoa stain strongly with PAS. The enucleated residual mass contains HgBB-positive proteins and lipid granules. The morphological and cytochemical changes occurring during various spermatogenic stages are correlated with corresponding histoenzymological changes in the cytoplasm. The frequency of spermatogenesis indicated that the transformation of secondary spermatogonia into spermatids is relatively fast as compared to that of primary spermatogonia into secondary spermatogonia and stages of spermateleosis.