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An analysis of variations in the age structure of Fasciola hepatica populations in sheep

Published online by Cambridge University Press:  06 April 2009

Gary Smith
Gary Smith
Affiliation:
Department of Zoology and Applied Entomology, Imperial College, Prince Consort Road, London SW7 2AZ
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Summary

The processes which govern the age structure of Fasciola hepatica populations in sheep were investigated by means of a simple mathematical model. The mortality of the metacercariae on the pasture was shown to be a factor of major importance. The mortality rate depends on the micro-climate that prevails at the pasture surface, and thus the age distribution curve of a population of flukes is also determined in part by the weather. This has important implications for the chemotherapy of fascioliasis: flukicides are not equally effective over the whole range of age-classes of parasite and so the factors which govern the age distribution curve of the parasite population within individual hosts ultimately determine the efficiency of chemotherapy.

Type
Research Article
Information
Parasitology , Volume 84 , Issue 1 , February 1982 , pp. 49 - 61
Copyright
Copyright © Cambridge University Press 1982

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