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The reversibility of constraints on size and fecundity in the parasitic nematode Strongyloides ratti

Published online by Cambridge University Press:  04 July 2006

M. E. VINEY ,
M. D. STEER  and
C. P. WILKES
M. E. VINEY
Affiliation:
School of Biological Sciences, University of Bristol, Woodland Road, Bristol BS8 1UG, UK
M. D. STEER
Affiliation:
School of Biological Sciences, University of Bristol, Woodland Road, Bristol BS8 1UG, UK
C. P. WILKES
Affiliation:
School of Biological Sciences, University of Bristol, Woodland Road, Bristol BS8 1UG, UK
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Abstract

The size and fecundity of parasitic nematodes are constrained by the host immune response. For the parasitic nematode of rats, Strongyloides ratti, parasitic females infecting immunized rats are smaller and less fecund than those infecting naïve rats. Here, we investigated whether these constraints on size and fecundity are life-long. This was done by comparison of worms from different immunization and immunosuppression regimes. It was found that the per capita fecundity of parasitic females of S. ratti is fully reversed, but that their size is only partially reversed, if previously immunized hosts are subsequently immunosuppressed, suggesting that fecundity is not subject to life-long constraints. The host immune response also resulted in allometric changes in the parasitic females. The significance of these results with respect to the growth and control of nematode fecundity are discussed.

Keywords

sizefecundityimmune pressureallometry
Type
Research Article
Information
Parasitology , Volume 133 , Issue 4 , October 2006 , pp. 477 - 483
Copyright
© 2006 Cambridge University Press

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