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Observations on the morphology of Toxocara pteropodis eggs

Published online by Cambridge University Press:  05 June 2009

Paul Prociv
Paul Prociv
Affiliation:
Department of Parasitology, The University of Queensland, St. Lucia, Queensland 4067, Australia
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Abstract

Fertile eggs of Toxocara pteropodis, passed in the faeces of juvenile flying-foxes, were ovoid to spheroid in shape with a diameter range of 80–110 µm. The shell was often seen to comprise 4 layers: a fine inner lipid layer, a thicker clear chitinous layer, an equally thick outer vitelline layer and a pitted outermost, proteinaceous uterine layer of variable thickness. Infertile eggs were less uniform in shape and generally did not have well-defined shell layers, the formation of which is triggered by sperm penetration of the oocyte. The eggs of this species are bulkier than those of related ascaridoids, apparently because of a thicker external coat which, while not providing mechanical strength, is thought to protect against desiccation. Scanning electron microscopical findings suggest that the outer layer is not applied directly by uterine cells, but forms by the gradual deposition of secretions in the uterine lumen, regardless of whether the oocyte has been fertilized.

Keywords

Toxocara pteropodisovamorphologyscanning electron microscopy
Type
Research Article
Information
Journal of Helminthology , Volume 64 , Issue 4 , December 1990 , pp. 271 - 277
Copyright
Copyright © Cambridge University Press 1990

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References

REFERENCES

Douglas, J. R. & Baker, N. R. (1965) Some host-parasite relationships of canine helminths. In: Proceedings of the 26th Biological Colloquium (editor Mccauley, J.E.) pp. 97–115. Oregon State University Press; Corvallis.Google Scholar
Foor, W. E. (1967) Ultrastructural aspects of oocyte development and shell formation in Ascaris lumbricoides. Journal of Parasitology, 53, 1245–1262.Google Scholar
Foor, W. E. (1983) Nematoda. In: Reproductive biology of invertebrates. Vol I: Oogenesis, oviposition and oosorption.(editors, Adiyodi, A. and Adiyodi, R.) pp. 223–256.John Wiley & Sons: New York.Google Scholar
Kazacos, K. R. & Turek, J. J. (1983) Scanning electron microscopy of the eggs of Baylisascaris procyonis, B. transfuga and Parascaris equorum, and their comparison with Toxocara canis and Ascaris suum. Proceedings of the Helminthological Society of Washington, 50, 36–42.Google Scholar
Mozgovoi, A. A. (1953) Ascaridata of animals and man and the diseases caused by them. In: Essentials of Nematology, Vol II, Pt 2, Monograph Series of the Helminthological Laboratory of the USSR. USSR Academy of Sciences Publishers: Moscow (in Russian).Google Scholar
Prociv, P. (1985) Observations on the prevalence and possible infection source of Toxocara pteropodis (Nematoda: Ascaridoidea) in Queensland flying-foxes. Australian Mammalogy, 8, 319–323.Google Scholar
Prociv, P. (1986) Toxocara pteropodis, T. canis and T. cati infections in guinea pigs. Tropical Biomedicine, 3, 97–106.Google Scholar
Prociv, P. (1989) Observations on egg production byToxocara pteropodis. International Journal for Parasitology, 19, 441–443.Google Scholar
Prociv, P. & Brindley, P. J. (1986) Oral, parenteral and paratenic infections of mice withToxocara pteropodis. International Journal for Parasitology, 16, 471–474.Google Scholar
Refuerzo, P. G., Albis-Jimenez, F. S. & De La Cerna, G. (1954) Studies on Neoascaris vitulorum. I. Observations on the morphology of the ova and on their development to the infective stage with notes on feeding experiments. Philippine Journal of Animal Industry, 13, 15–23.Google Scholar
Ubelaker, J. E. & Allison, V. F. (1975) Scanning electron microscopy of the eggs of Ascaris lumbricoides, A. suum, Toxocara canis and T. mystax. Journal of Parasitology, 61, 802–807.Google Scholar
Warren, E. G. (1971) Studies on the morphology and taxonomy of the genera Toxocara Stiles, 1905 and Neoascaris Travassos, 1927. Zoologischer Anzeiger, 185, 393–442.Google Scholar
Wharton, D. A. (1979) Ascaris sp.: water loss during desiccation of embryonating eggs. Experimental Parasitology, 48, 398–406.Google Scholar
Wharton, D. A. (1980) Nematode egg-shells. Parasitology, 81, 447–463.Google Scholar