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Hymenolepis nana: the fine structure of the embryonic envelopes

Published online by Cambridge University Press:  06 April 2009

I. Fairweather
Affiliation:
Department of Zoology, The Queen's University, Belfast BT7 1NN
L. T. Threadgold
Affiliation:
Department of Zoology, The Queen's University, Belfast BT7 1NN

Summary

The fine structure of the envelopes surrounding hatched and unhatched oncospheres of Hymenolepis nana has been investigated by transmission and scanning electron microscopy (SEM), together with light microscope histochemical observations of JB-4 embedded material. The oncosphere is surrounded by 3 layers – the capsule, the outer envelope and the inner envelope, the latter giving rise to the embryophore and the ‘oncospheral membrane’. An additional layer – the polar filament layer – lies between the ‘oncospheral membrane’ and the oncosphere. Shell material is deposited on the capsule as a thin layer. It is secreted by the outer envelope, which degenerates once shell formation is complete. The uterus may also contribute to shell formation. The embryophore forms a thin, incomplete and peripheral layer within the inner envelope. In the basal region of this envelope, partial development of an ‘oncospheral membrane’ takes place, but it does not become detached as a separate layer. The polar filaments, which are characteristic of the oncosphere of H. nana, are derived from the epithelial covering of the oncosphere itself, which delaminates to form a separate polar filament layer. The filaments arise from knob-like projections at opposite poles of this layer. The design of the embryonic envelopes in H. nana show a number of modifications from the basic cyclophyllidean pattern, and these can be related to the demands of its ‘direct’ life-cycle.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1981

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References

REFERENCES

Berntzen, A. K. & Voge, M. (1962). In vitro hatching of oncospheres of Hymenolepis nana and Hymenolepis citelli (Cestoda: Cyclophyllidea). Journal of Parasitology 48, 110–19.CrossRefGoogle ScholarPubMed
Berntzen, A. K. & Voge, M. (1965). In vitro hatching of oncospheres of four hymenolepidid cestodes. Journal of Parasitology 51, 235–42.Google Scholar
Beveridge, I., Rickard, M. D., Gregory, G. G. & Munday, B. L. (1975). Studies on Anoplotaenia dasyuri Beddard, 1911 (Cestoda: Taeniidae), a parasite of the Tasmanian devil: observations on the egg and metacestode. International Journal for Parasitology 5, 257–67.CrossRefGoogle ScholarPubMed
Caley, J. (1975). In vitro hatching of the tapeworm Moniezia expansa (Cestoda: Anoplocephalidae) and some properties of the egg membranes. Zeitschrift für Parasitenkunde 45, 335–46.CrossRefGoogle ScholarPubMed
Coil, W. H. (1967). Observations on the embryonic development of the cyclophyllidean cestode Diplophallus polymorphus with emphasis on the histochemistry of the egg membranes. Zeitschrift für Parasitenkunde 29, 356–73.CrossRefGoogle ScholarPubMed
Coil, W. H. (1968). Observations on the embryonic development of the dioecious tapeworm Infula macrophallus with emphasis on the histochemistry of the egg membranes. Zeitschrift für Parasitenkunde 30, 301–17.CrossRefGoogle Scholar
Coil, W. H. (1970). Studies on the biology of the tapeworm Shipleya inermis Fuhrmann, 1908. Zeitschrift für Parasitenkunde 35, 4054.CrossRefGoogle Scholar
Coil, W. H. (1975). The histochemistry and fine structure of the embryophore of Shipleya inermis (Cestoda). Zeitschrift für Parasitenkunde 48, 914.CrossRefGoogle ScholarPubMed
Coil, W. H. (1977). Studies on the embryogenesis of the tapeworm Shipleya inermis Fuhrmann, 1908 using transmission and scanning electron microscopy. Zeitschrift für Parasitenkunde 52, 311–18.CrossRefGoogle ScholarPubMed
Coil, W. H. (1979). Studies on the embryogenesis of the tapeworm Cittotaenia variabilis (Stiles, 1895) using transmission and scanning electron microscopy. Zeitschrift für Parasitenkunde 59, 151–9.CrossRefGoogle ScholarPubMed
Collin, W. K. (1968). Electron microscope studies of the muscle and hook systems of hatched oncospheres of Hymenolepis citelli McLeod, 1933 (Cestoda: Cyclophyllidea). Journal of Parasitology 54, 7488.CrossRefGoogle ScholarPubMed
Collin, W. K. (1970). Electron microscopy of postembryonic stages of the tapeworm, Hymenolepis citelli. Journal of Parasitology 56, 1159–70.CrossRefGoogle ScholarPubMed
Fairweather, I. & Threadgold, L. T. (1981). Hymenolepis nana: the fine structure of the ‘penetration gland’ and nerve cells within the oncosphere. Parasitology 82, 445458.Google Scholar
Lethbridge, R. C. (1976). The architecture of the eggshell of Hymenolepis diminuta. International Journal for Parasitology 6, 8790.CrossRefGoogle ScholarPubMed
Morseth, D. J. (1965). Ultrastructure of developing taeniid embryophores and assorted structures. Experimental Parasitology 16, 207–16.Google Scholar
Morseth, D. J. (1966). Chemical composition of embryophoric blocks of Taenia hydatigena, Taenia ovis, and Taenia pisiformis eggs. Experimental Parasitology 18, 347–54.CrossRefGoogle ScholarPubMed
Nieland, M. L. (1968). Electron microscope observations on the egg of Taenia taeniaeformis. Journal of Parasitology 54, 957–69.CrossRefGoogle ScholarPubMed
Pence, D. B. (1967). The fine structure and histochemistry of the infective eggs of Dipylidium caninum. Journal of Parasitology 53, 1041–54.CrossRefGoogle ScholarPubMed
Pence, D. B. (1970). Electron microscope and histochemical studies on the eggs of Hymenolepis diminuta. Journal of Parasitology 56, 8497.CrossRefGoogle ScholarPubMed
Rybicka, K. (1972). Ultrastructure of embryonic envelopes and their differentiation in Hymenolepis diminuta (Cestoda). Journal of Parasitology 58, 849–63.CrossRefGoogle ScholarPubMed
Rybicka, K. (1973 a). Ultrastructure of macromeres in the cleavage of Hymenolepis diminuta (Cestoda). Transactions of the American Microscopical Society 92, 241–55.CrossRefGoogle ScholarPubMed
Rybicka, K. (1973 b). Ultrastructure of the embryonic syncytial epithelium in a cestode Hymenolepis diminuta. Parasitology 66, 918.CrossRefGoogle Scholar
Seidel, J. S. & Voge, M. (1975). Axenic development of cysticercoids of Hymenolepsis nana. Journal of Parasitology 61, 861–4.Google Scholar
Smyth, J. D. (1962). Introduction to Animal Parasitology. London: The English Universities Press Ltd.Google Scholar
Smyth, J. D. (1969). The Physiology of Cestodes. Edinburgh: Oliver and Boyd Ltd.Google Scholar
Swiderski, Z. (1968). Electron-microscopy of embryonic envelope formation by the cestode Catenotaenia pusilla. Experimental Parasitology 23, 104–13.CrossRefGoogle Scholar
Swiderski, Z. (1972). La structure fine de l'oncosphere du cestode Catenotaenia pusilla (Goeze, 1782) (Cyclophyllidea, Catenotaeniidae). La Cellule 69, 205–37.Google Scholar
Swiderski, Z. & Eckert, J. (1977). Electron microscope and histochemical studies on the oncosphere of Echinococcus granulosus. Parasitology 75, i.Google Scholar
Thomas, H. (1971). Untersuchungen zur Infektionsfähigkeit von Hymenolepis nana–Eiern. Zeitschrift für Parasitenkunde 37, 330–5.CrossRefGoogle Scholar
Voge, M. & Berntzen, A. K. (1961). In vitro hatching of oncospheres of Hymenolepis diminuta (Cestoda: Cyclophyllidea). Journal of Parasitology 47, 813–18.CrossRefGoogle ScholarPubMed