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Faecal egg counts and nematode fecundity: Heligmosomoides polygyrus and laboratory mice

Published online by Cambridge University Press:  06 April 2009

A. E. Keymer  and
R. W. Hiorns
A. E. Keymer
Affiliation:
Department of Zoology, South Parks Road, Oxford OX1 3PS
R. W. Hiorns
Affiliation:
Department of Biomathematics, South Parks Road, Oxford OX1 3UB
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Summary

The results are presented of an experimental investigation of the relationship between faecal egg counts and worm burden in outbred MF1 mice infected with Heligmosomoides polygyrus (Nematoda). The sex-ratio of the adult parasites was found to be significantly female biased, but independent of parasite burden. Evidence was also found to suggest a significant association between parasite density and mating success. The linear logarithmic relationship (gradient of approximately 2) between the variance and mean of repeated egg counts from individual mice could not be disrupted by controlled experimental conditions, and is therefore concluded to be an inherent feature of the biology of helminth-host interactions. A significant positive association was detected between host faecal output and parasite fecundity; further investigation of the cause of this association is now required. Average faecal production was found to be inversely related to worm burden. In combination, the above two factors account partly, but not completely, for the observed density dependence in the absolute rate of parasite egg production. Two epidemiological consequences of the relationship between faecal production and parasite fecundity are discussed. First, absolute rates of egg production can only be estimated by temporal egg counts (epd). Secondly, measurements of egg production/g of faecal material (epg) are more reliable indicators of worm burden than measurements of epd. Both faecal output and worm fecundity respond as might be predicted to a period of host food deprivation; faecal egestion and measurements of epd are signifcantly depressed, and measurements of epg are significantly increased. The data are consistent with the hypothesis that egg production and faecal output are causally associated, but that other factors relating to parasite density also influence egg production. Of the possible causes for the high variability in parasite egg production between mice harbouring low number of worms, the most likely explanation seems to be host heterogeneity (possible genetic in origin). This is discussed in relation to similar patterns observed in data collected from human populations in areas of endemic helminth infection.

Type
Research Article
Information
Parasitology , Volume 93 , Issue 1 , August 1986 , pp. 189 - 203
Copyright
Copyright © Cambridge University Press 1986

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References

Anderson, R. M. & May, R. M. (1985 a). Helminth infections of humans: mathematical models, population dynamics and control. Advances in Parasitology 24, 1–101.CrossRefGoogle ScholarPubMed
Anderson, R. M. & May, R. M. (1985 b). Herd immunity to helminth infection and implications for parasite control. Nature, London 315, 493–6.CrossRefGoogle ScholarPubMed
Anderson, R. M. & Schad, G. A. (1985). Hookworm burdens and faecal egg counts: an analysis of the biological basis of variation. Transactions of the Royal Society of Tropical Medicine and Hygiene 79, 812–25.CrossRefGoogle ScholarPubMed
Bawden, R. J. (1969). Some effects of the diet of mice on Nematospiroides dubius. Parasitology 59, 203–13.CrossRefGoogle Scholar
Behnke, J. M. & Robinson, M. (1985). Genetic control of immunity to Nematospiroides dubius: a 9 day anthelminithic abbreviated immunising regime which separates weak and strong responder strains of mice. Parasite Immunology 7, 232–53.CrossRefGoogle ScholarPubMed
Bundy, D. A. P., Thompson, D. E., Cooper, E. S., Golden, M. N. H. & Anderson, R. M. (1985). Population dynamics and chemotherapeutic control of Trichuris trichiura in children in Jamaica and St. Lucia. Transactions of the Royal Society of Tropical Medicine and Hygiene 79, 759–65.CrossRefGoogle ScholarPubMed
Chai, J. Y., Hong, S. T., Lee, S. H. & Seo, B. S. (1981). Fluctuation of the egg production amounts according to worm burden and length of Ascaris lumbricoides. Korean Journal of Parasitology 19, 38–43.CrossRefGoogle ScholarPubMed
Croll, N. S., Anderson, R. M., Gyorkos, T. W. & Ghadirian, E. (1982). The population biology and control of Ascaris lumbricoides in a rural community in Iran. Transactions of the Royal Society of Tropical Medicine and Hygiene 76, 187–97.CrossRefGoogle Scholar
Crompton, D. W. T. (1984). Influence of parasitic infection on food intake. Federation Proceedings 43, 239–45.Google ScholarPubMed
Cypess, R. H., Lucia, H. L., Zidian, J. L. & Rivera-Ortiz, C. I. (1977). Heligmosomoides polygyrus: temporal, spatial and morphological population characteristics in LAF, IJ mice. Experimental Parasitology 42, 34–43.CrossRefGoogle Scholar
Dunn, A. & Keymer, A. E. (1986). Factors affecting the reliability of the McMaster technique. Journal of Helminthology (submitted).CrossRefGoogle ScholarPubMed
Hall, A. (1982). Intestinal helminths of man: the interpretation of egg counts. Parasitology 85, 605–13.CrossRefGoogle ScholarPubMed
Kerboeuf, D. & Jolivet, G. (1980). Repeated anthelminthic treatments and receptivity of mice to experimental infections with Nematospiroides dubius. Annales de Recherches Vétérinaires 11, 185–93.Google ScholarPubMed
Keymer, A. E. & Hiorns, R. W. (1986). Heligmosomoides polygyrus: dynamics of primary and repeated infection in outbred mice. Proceedings of the Royal Society of London, B (In the Press).Google ScholarPubMed
Krupp, I. M. (1961), Effects of crowding and of superinfection on habitat selection and egg production in Ancylostoma caninum. Journal of Parasitology 47, 957–61.CrossRefGoogle ScholarPubMed
Lewis, J. W. (1968). Studies of the helminth parasites of the long-tailed field mouse Apodemus sylvaticus sylvaticus from Wales. Journal of the Zoological Society of London 154, 287–312.CrossRefGoogle Scholar
M.A.F.F. (1977). Manual of Veterinary Parasitological Techniques. Technical Bulletin No. 18, H.M.S.O., London.Google Scholar
Martin, J., Keymer, A. E., Isherwood, R. J. & Wainwright, S. M. (1983). The prevalence and intensity of Ascaris lumbricoides in Moslem children from Northern Bangladesh. Transactions of the Royal Society of Tropical Medicine and Hygiene 77, 702–6.CrossRefGoogle ScholarPubMed
Medley, G. F. & Anderson, R. M. (1985). Density-dependent fecundity in Schistosoma mansoni infections in man. Transactions of the Royal Society of Tropical Medicine and Hygiene 79, 532–4.CrossRefGoogle ScholarPubMed
Moriya, S. (1954). The reliability of the current diagnostic methods for the identification of helminth eggs. Parasitology 44, 300–303.CrossRefGoogle ScholarPubMed
Seo, B. S., Cho, S. Y. & Chai, J. Y. (1979). Egg discharging patterns of Ascaris lumbricoides in low worm burden cases. Korean Journal of Parasitology 17, 98–104.CrossRefGoogle ScholarPubMed
Sinniah, B. (1982). Daily egg production of Ascaris lumbricoides: the distribution of eggs in the faeces and the variability of egg counts. Parasitology 84, 167–75.CrossRefGoogle ScholarPubMed
Stoll, N. R. (1923). Investigations on the control of hookworm disease. XVIII. On the relation between the number of eggs found in human faeces and the number of hookworms in the host. American Journal of Hygiene 3, 156–79.Google Scholar
Yazima, F. & Machida, K. (1958). On the ecological relations of parasite state of Ancylostoma caninum, especially on the density effect of population. Japanese Journal of Parasitology 7, 631–40.Google Scholar