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Differential association between circulating testosterone and infection risk by several viruses in natural cat populations: a behavioural-mediated effect?

Published online by Cambridge University Press:  03 January 2013

E. HELLARD ,
D. FOUCHET ,
B. REY ,
A. MOUCHET ,
H. POULET  and
D. PONTIER
E. HELLARD*
Affiliation:
Laboratoire de Biométrie et Biologie Evolutive, Université de Lyon, Université Lyon I, CNRS, UMR 5558, 43 Bd du 11 novembre 1918, 69622, Villeurbanne, France
D. FOUCHET
Affiliation:
Laboratoire de Biométrie et Biologie Evolutive, Université de Lyon, Université Lyon I, CNRS, UMR 5558, 43 Bd du 11 novembre 1918, 69622, Villeurbanne, France
B. REY
Affiliation:
Laboratoire de Biométrie et Biologie Evolutive, Université de Lyon, Université Lyon I, CNRS, UMR 5558, 43 Bd du 11 novembre 1918, 69622, Villeurbanne, France
A. MOUCHET
Affiliation:
Laboratoire de Biométrie et Biologie Evolutive, Université de Lyon, Université Lyon I, CNRS, UMR 5558, 43 Bd du 11 novembre 1918, 69622, Villeurbanne, France
H. POULET
Affiliation:
Merial, Laboratoire de Lyon Gerland, 254 rue Marcel Mérieux, 69007 Lyon, France
D. PONTIER
Affiliation:
Laboratoire de Biométrie et Biologie Evolutive, Université de Lyon, Université Lyon I, CNRS, UMR 5558, 43 Bd du 11 novembre 1918, 69622, Villeurbanne, France
*
*Corresponding author: Laboratoire de Biométrie et Biologie Evolutive, Université de Lyon, Université Lyon I, CNRS, UMR 5558, 43 Bd du 11 novembre 1918, 69622, Villeurbanne, France. Tel: +33 (0) 4 72 44 84 37. Fax: +33 (0) 4 72 43 13 88. E-mail: eleonore.hellard@gmail.com
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Summary

Testosterone is involved in the development and expression of physiological, morphological and behavioural traits. High levels are often associated with high infection risk and/or intensity, suggesting a trade-off between sexual traits and immunity. Classically invoked mechanisms are immunological or behavioural, i.e., testosterone increases susceptibility or resistance to parasites via an impact on immunity or modulates behaviours involved in parasite transmission. However, studies report contrasted patterns. Given its modes of action and the diversity of host-parasite interactions, testosterone should not act similarly on all interactions. To reduce host and context diversity, we studied 3 viruses in the same cat population: the aggressively transmitted Feline Immunodeficiency virus (FIV), and the Feline Calicivirus (FCV) and Herpesvirus (FHV) both transmitted during friendly contacts. Testosterone had a strong effect on the probability of being positive to FIV whereas its effect was significantly weaker on FCV and FHV. These findings demonstrate that testosterone can be differentially associated with parasites of the same type (viruses). The difference we observed was consistent with a behavioural-mediated effect (increased aggressiveness), supporting the idea that the testosterone effect on infection risk is at least partially driven by behavioural mechanisms in our system. Further investigations (e.g., individual immunity measures) are required to confirm this hypothesis.

Keywords

aggressively-transmitted parasitesmulti-parasitismFeline calicivirusFeline herpesvirusFeline immunodeficiency virus
Type
Research Article
Information
Parasitology , Volume 140 , Issue 4 , April 2013 , pp. 521 - 529
Copyright
Copyright © Cambridge University Press 2013

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