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Observations on the fine structural changes associated with schizogony and gametogony in Eimeria tenella

Published online by Cambridge University Press:  06 April 2009

Diane J. McLaren
Diane J. McLaren
Affiliation:
Research Institute, Smith, Kline and French Laboratories, Welwyn Garden City, Herts.
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Extract

Changes associated with schizogony and gametogony in Eimeria tenella have been studied by means of electron microscopy.

In infections of E. tenella both small and large schizonts are formed, and in both cases merozoites are developed by a surface ‘budding’ mechanism. The final severance of the merozoite from the schizont appears to give rise to the dorsal pore of the merozoite. Newly formed merozoites contain structures which are absent in the mature organism.

Early in microgametogony the nucleus of the microgametocyte divides repeatedly to produce a number of smaller nuclei which migrate peripherally in the cell. The chromatin aggregates into the peripheral part of each nucleus, which then elongates to form the nucleus of the of microgamete. That part of the gametocyte nucleus which is devoid of chromatin, probably gives rise to the perforatorium and three flagella of the gamete. Residual material is left in the gametocyte cytoplasm in the form of a gametogenic cyst.

‘Wall-forming’ bodies are present in the earliest macrogametocyte and ‘dark bodies’ are developed later. After fertilization these bodies migrate to the periphery of the zygote. In E. tenella the oocyst wall is trilaminate. The limiting membrane of the zygote separates from the cell to become the outermost membrane of the cyst wall. The middle layer of the cyst wall is developed from the ‘dark bodies’, and the ‘wall forming’ bodies give rise to the inner layer of the oocyst wall.

Type
Research Article
Information
Parasitology , Volume 59 , Issue 3 , August 1969 , pp. 563 - 574
Copyright
Copyright © Cambridge University Press 1969

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References

REFERENCES

Andreassen, J. & Behnke, O. (1968). Fine structure of the merozoites of a rat coccidian Eimeria miyairii with a comparison of the fine structure of other Sporozoa. J. Parasit. 54, 150–63.CrossRefGoogle ScholarPubMed
Cheissin, E. M. (1958). Cytologische Untersuchungen verschiedener Stadien des Lebenszyklus der Kaninchencoccidien. I. Eimeria intestinalis. Arch. Protistenk. 102, 265–90.Google Scholar
Cheissin, E. M. (1965). Electron microscope study of the microgametogenesis in two species of coccidia from rabbit (Eimeria magna and Eimeria intestinalis). Acta Protozool. 3, 215–24.Google Scholar
Colley, F. C. (1968 a). Fine structure of microgametocytes and macrogametocytes of Eimeria nieschulzi. J. Protozool. 14, 663–74.Google Scholar
Colley, F. C. (1968 b). Fine structure of schizonts and merozoites of Eimeria nieschulzi J. Protozool. 15, 374–82.Google Scholar
Doflein, F. & Reichenow, E. (1953). Lehrbuch der Protozoenkunde, p. 1213. Jena: Fischer Verlag.Google Scholar
Hammond, D. M., Scholtyseck, E. & Miner, M. L. (1967). The fine structure of microgametocytes of Eimeria perforans, Eimeria stiedae, Eimeria bovis and Eimeria aubernensis. J. Parasit. 53, 235–47.Google Scholar
Hammond, D. M., Scholtyseck, E. & Chobotar, B. (1968). Fine structures associated with nutrition of the intracellular parasite Eimeria aubernensis. J. Protozool. 14, 678–83.Google Scholar
McLaren, D. J. & Paget, G. E. (1968). A fine structural study on the merozoite of Eimeria tenella with special reference to the conoid apparatus. Parasitology 58, 561–71.CrossRefGoogle Scholar
Millonig, G. (1961). Advantages of a phosphate buffer for osmium tetroxide solutions in fixation. J. appl. Physiol. 32, 1637.Google Scholar
Pastillo, W. H. & Becker, E. R. (1955). Cytochemistry of Eimeria brunetti and Eimeria acervulina of the chicken. J. Morph. 96, 61–85.Google Scholar
Reich, F. (1913). Das Kaninchencoccid Eimeria stiedae, nebst einem Beitrage zur Kenntnis von Eimeria falciformis. Arch. Protozool. 28, 1–42.Google Scholar
Ryley, J. F. (1969). Ultrastructural studies on the sporozoite of Eimeria tenella. Parasitology (in the Press).CrossRefGoogle ScholarPubMed
Ryley, J. F., Bentley, M., Manners, D. J. & Stark, J. R. (1969). Amylopectin, the storage polysaccharide of Coccidia. J. Parasit. (in the Press.)CrossRefGoogle ScholarPubMed
Scholtyseck, E. (1962). Über die Feinstruktur von Eimeria perforans (Sporozoa). Z. ParasitKde., 22, 123–32.Google Scholar
Scholtyseck, E. (1964). Elektronenmikroskopisch-chemischer Nachweis von Glycogen bei Eimeria perforans. Z. Zellforsch mikrosk. Anat. 64, 688–707.Google Scholar
Scholtyseck, E. (1965). Elektronenmikroskopische Untersuchungen über die Schizogonie bei Coccidien (Eimeria perforans und Eimeria stiedae). Z. ParasitKde 26, 50–62.Google Scholar
Scholtyseck, E., Hammond, D. M. & Ernst, J. V. (1966). Fine structure of the macrogametes of Eimeria perforans, E. steidae, E. bovis and E. aubernensis. J. Parasit. 52, 975–87.Google Scholar
Scholtyseck, E. & Voigt, W. H. (1963). Die Bildung der Oocystenhülle bei Eimeria perforans (Sporozoa) Z. Zellforsch. mikrosk. Anat. 62, 279–92.Google Scholar
Scholtyseck, E. & Weissenfels, N. (1956). Elekronenmikroscopische Untersuchungen von Sporozoen. I. Die Oocystenmembran des Hühnercoccids Eimeria tenella. Arch. Protozool. 101, 215–22.Google Scholar
Sheffield, H. G. & Hammond, D. M. (1967). Electron microscope observations on the development of first generation merozoites of Eimeria bovis. J. Parasit. 53, 831–46.CrossRefGoogle ScholarPubMed