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Eimeria mitis: a comparison of the endogenous developmental stages of a line selected for early maturation and the parent strain

Published online by Cambridge University Press:  06 April 2009

V. McDonald
Affiliation:
Houghton Poultry Research Station, Huntingdon, Cambs. PE17 2DA
M. W. Shirley
Affiliation:
Houghton Poultry Research Station, Huntingdon, Cambs. PE17 2DA

Summary

The endogenous development of the Houghton (H) strain of Eimeria mitis (= mivati) was compared with the life-cycle of a precocious (HP) line derived from the H strain. In both parasites 4 generations of schizonts which developed in epithelial cells were observed: the 1st and 2nd were found in the crypts and the 3rd and 4th in the villi. Gametocytes and zygotes occupied epithelial cells at the tips of the villi. The onset of gametogony normally coincided with the maturation of 4th-generation schizonts. The infection was confined initially to an area of the gut extending from the jejunum to the ileo-caecal junction but 3rd-generation merozoites and subsequent stages were also found in the caeca and rectum. The life-cycle of the precocious line was shorter than that of the parent strain. Gametocytes appeared to develop from 3rd-generation as well as from 4th-generation merozoites. Also, sporozoites of the precocious line transformed to trophozoites before those of the parent strain. First-generation schizonts of the HP line tended to be smaller and to contain fewer merozoites than those of the H strain. The differences between the life-cycles of the two parasites account for the lower reproductive potential of the precocious line.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1984

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References

REFERENCES

Cooper, D. M. & Timms, J. R. (1972). The rearing and maintenance of breeding chickens in isolators. 1. Glassfibre isolators. Avian Pathology 1, 4557.Google Scholar
Jeffers, T. K. (1975). Attenuation of Eimeria tenella through selection for precociousness. Journal of Parasitology 61, 1083–90.CrossRefGoogle ScholarPubMed
Jeffers, T. K. (1976). Genetic recombination of precociousness and anticoccidial drug resistance in Eimeria tenella. Zeitschrift für Parasitenkunde 50, 251–5.CrossRefGoogle ScholarPubMed
Joyner, L. P. (1958). Experimental Eimeria mitis infections in chickens. Parasitology 48, 101–12.CrossRefGoogle ScholarPubMed
Long, P. L. (1967). Studies on Eimeria mivati in chickens and a comparison with Eimeria acervulina. Journal of Comparative Pathology 77, 315–25.CrossRefGoogle Scholar
Long, P. L. (1971). Maintenance of intestinal protozoa in vivo with particular reference to Eimera and Histomonas. In The Maintenance of Parasites in Vivo (ed. Taylor, A. E. R. and Muller, R.) Proceedings of the 9th Symposium of the British Society for Parasitology, pp. 6575.Google Scholar
McDonald, V. & Ballingall, S. (1983 a). Attenuation of Eimeria mivati (=mitis) by selection for precocious development. Parasitology 86, 361–9.CrossRefGoogle ScholarPubMed
McDonald, V. & Ballingall, S. (1983 b). Further investigation of pathogenicity, immunogenicity and stability of precocious Eimeria acervulina. Parasitology 86, 371–9.CrossRefGoogle ScholarPubMed
McDonald, V., Ballingall, S. & Shirley, M. W. (1982). A preliminary study of the nature of infection and immunity in chickens given an attenuated line of Eimeria acervulina. Parasitology 84, 2130.CrossRefGoogle ScholarPubMed
McDougald, L. R. & Jeffers, T. K. (1976). Eimeria tenella (Sporozoa: Coccidia): gametogony following a single asexual generation. Science 192, 258–9.CrossRefGoogle ScholarPubMed
Norton, C. C. & Joyner, L. P. (1980). Studies with Eimeria acervulina and E. mivati: pathogenicity and cross immunity. Parasitology 81, 315–23.CrossRefGoogle Scholar
Norton, C. C. & Joyner, L. P. (1981). Eimeria acervulina and E. mivati oocysts, life-cycle and ability to develop in the chicken embryo. Parasitology 83, 269–79.CrossRefGoogle Scholar
Shirley, M. W. (1975). Enzyme variation in Eimeria species of the chicken. Parasitology 71, 269–76.CrossRefGoogle ScholarPubMed
Shirley, M. W. (1979). A reappraisal of the taxonomic status of Eimeria mivati, Edgar and Seibold 1964, by enzyme electrophoresis and cross-immunity tests. Parasitology 78, 221–37.CrossRefGoogle ScholarPubMed
Shirley, M. W., Jeffers, T. K. & Long, P. L. (1983). Studies to determine the taxonomic status of Eimeria mitis, Tyzzer 1929 and E. mivati, Edgar and Seibold 1964. Parasitology 87, 185–98.CrossRefGoogle Scholar
Tyzzer, E. E. (1929). Coccidiosis in gallinaceous birds. American Journal of Hygiene 10, 269383.Google Scholar