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The selection of experimental doses and their importance for parasite success in metacercarial infection studies

Published online by Cambridge University Press:  22 December 2009

R. POULIN*
Affiliation:
Department of Zoology, University of Otago, PO Box 56, Dunedin, New Zealand
*
*Corresponding author: Tel: +64 3 479 7983. Fax: +64 3 479 7584. E-mail: robert.poulin@stonebow.otago.ac.nz

Summary

Experimental studies of parasite transmission are essential for advances in basic and applied parasitology. A survey of the results of published experiments can identify the determinants of both variation among studies in experimental design and of parasite infection success. Here, analyses are conducted on data compiled from a total of 106 metacercarial infection experiments (35 on Echinostomatidae, 37 on Fasciolidae, 34 on other trematodes) obtained from 83 studies. All of these involved experimental oral infection of individual definitive hosts by a single known dose of metacercariae under controlled conditions. Across these studies, the metacercarial dose used (i) was typically about 10 times higher than the average natural dose that could be acquired by feeding on intermediate hosts (for taxa other than Fasciolidae), and (ii) showed a positive relationship with the body mass of the definitive host, although this relationship was only significant for Fasciolidae. Although the chosen dose was rarely justified, the larger the definitive host, the more metacercariae it received. Among Echinostomatidae and Fasciolidae, there was also a significant dose-dependent effect on infection success: the higher the dose used in an experiment, the smaller the proportion of metacercariae recovered from the host. This effect was mitigated by definitive host body mass, with infection success being generally lower in larger definitive hosts. For Echinostomatidae, the taxonomic identity of the definitive host also mattered, with metacercariae achieving higher infection success in mammals than in birds. The present findings suggest that the design of experimental infection studies requires greater consideration if their results are to yield useful biological insights.

Type
Research Article
Copyright
Copyright © Cambridge University Press 2009

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References

REFERENCES

Alcala-Canto, Y., Ibarra-Velarde, F., Sumano-Lopez, H., Gracia-Mora, J. and Alberti-Navarro, A. (2007). Effect of a cysteine protease inhibitor on Fasciola hepatica (liver fluke) fecundity, egg viability, parasite burden, and size in experimentally infected sheep. Parasitology Research 100, 461465.CrossRefGoogle ScholarPubMed
Ben-Ami, F., Regoes, R. R. and Ebert, D. (2008). A quantitative test of the relationship between parasite dose and infection probability across different host-parasite combinations. Proceedings of the Royal Society of London, B 275, 853859.Google ScholarPubMed
Bush, A. O., Heard, R. W. and Overstreet, R. M. (1993). Intermediate hosts as source communities. Canadian Journal of Zoology 71, 13581363.CrossRefGoogle Scholar
de Nunez, M. O. (2007). Life cycle of Stephanoprora uruguayense (Digenea: Echinostomatidae) in Argentina. Journal of Parasitology 93, 10901096.CrossRefGoogle Scholar
de Roode, J. C., Gold, L. R. and Altizer, S. (2007). Virulence determinants in a natural butterfly-parasite system. Parasitology 134, 657668.CrossRefGoogle Scholar
Fellous, S. and Koella, J. C. (2009). Infectious dose affects the outcome of the within-host competition between parasites. American Naturalist 173, E177E184.CrossRefGoogle ScholarPubMed
Fried, B. and Graczyk, T. K. (2000). Echinostomes as Experimental Models for Biological Research. Kluwer Academic Publishers, Dordrecht, The Netherlands.CrossRefGoogle Scholar
Galaktionov, K. V. and Dobrovolskij, A. A. (2003). The Biology and Evolution of Trematodes. Kluwer Academic Publishers, Dordrecht, The Netherlands.CrossRefGoogle Scholar
Gonzalez-Lanza, C., Manga-Gonzalez, M. Y. and Revilla-Nuin, B. (2006). Preliminary protective capacity study of a Dicrocoelium dendriticum antigenic protein in hamsters. Parasitology Research 99, 749752.CrossRefGoogle ScholarPubMed
Harvey, P. H. (1982). On rethinking allometry. Journal of Theoretical Biology 95, 3741.CrossRefGoogle ScholarPubMed
Kay, H., Murrell, D., Hansen, A. K., Madsen, H., Trang, N. T. T., Hung, N. M. and Dalsgaard, A. (2009). Optimization of an experimental model for the recovery of adult Haplorchis pumilio (Heterophyidae: Digenea). Journal of Parasitology 95, 629633.CrossRefGoogle ScholarPubMed
Muñoz-Antoli, C., Sotillo, J., Monteagudo, C., Fried, B., Marcilla, A. and Toledo, R. (2007). Development and pathology of Echinostoma caproni in experimentally infected mice. Journal of Parasitology 93, 854859.CrossRefGoogle ScholarPubMed
Platt, T. R. (2009). The course of a 300 metacercarial infection of Echinostoma caproni (Digenea: Echinostomatidae) in Institute for Cancer Research (ICR) mice. Comparative Parasitology 76, 15.CrossRefGoogle Scholar
Poulin, R. (2000). Variation in the intraspecific relationship between fish length and intensity of parasitic infection: biological and statistical causes. Journal of Fish Biology 56, 123137.CrossRefGoogle Scholar
Poulin, R. (2010). The scaling of dose with host body mass and the determinants of success in experimental cercarial infections. International Journal for Parasitology (in the Press). doi: 10.1016/j.ijpara.2009.09.001CrossRefGoogle ScholarPubMed
Poulin, R. and Cribb, T. H. (2002). Trematode life cycles: short is sweet? Trends in Parasitology 18, 176183.CrossRefGoogle ScholarPubMed
Poulin, R. and George-Nascimento, M. (2007). The scaling of total parasite biomass with host body mass. International Journal for Parasitology 37, 359364.CrossRefGoogle ScholarPubMed
Raadsma, H. W., Kingsford, N. M., Suharyanta, , Spithill, T. W. and Piedrafita, D. (2007). Host responses during experimental infection with Fasciola gigantica or Fasciola hepatica in Merino sheep. I. Comparative immunological and plasma biochemical changes during early infection. Veterinary Parasitology 143, 275286.CrossRefGoogle ScholarPubMed
Regoes, R. R., Hottinger, J. W., Sygnarski, L. and Ebert, D. (2003). The infection rate of Daphnia magna by Pasteuria ramosa conforms with the mass-action principle. Epidemiology and Infection 131, 957966.CrossRefGoogle ScholarPubMed
Reyes, P. M., Ibarra, V. F., Vera, M. Y., Canto, A. G., Hernandez, A., Hernandez, C. A., Castillo, R. and Villa, M. A. (2008). Paramphistomicidal efficacy of an experimental compound in sheep. Parasitology Research 102, 705708.CrossRefGoogle ScholarPubMed
Toledo, R., Espert, A., Muñoz-Antoli, C., Marcilla, A., Fried, B. and Esteban, J. G. (2005). Kinetics of antibodies and antigens in serum of mice experimentally infected with Echinostoma caproni (Trematoda: Echinostomatidae). Journal of Parasitology 91, 978980.CrossRefGoogle ScholarPubMed
Viozzi, G., Flores, V. and Rauque, C. (2005). An ectosymbiotic flatworm, Temnocephala chilensis, as second intermediate host for Echinoparyphium megacirrus (Digenea: Echinostomatidae) in Patagonia (Argentina). Journal of Parasitology 91, 229231.CrossRefGoogle ScholarPubMed
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