Genetics, Sex and Exposure: The Ecology of Heligmosomoides polygyrus (Nematoda) in the Wood Mouse

Abstract

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Helminth species richness in wild wood mice,Apodemus sylvaticus, is enhanced by the presence of the intestinal nematodeHeligmosomoides polygyrus

“…Both relationships are consistent with the idea that the long-lived H. polygyrus (Gregory et al 1990), like its close relative H. bakeri (which, being a parasite of house mice, Mus musculus, has been explored extensively in laboratory work ; Behnke, 1987 ;Behnke et al 1992 ;Monroy and Enriquez, 1992), is aided in its survival strategy in wood mice by suppressing its host's capacity to mount protective immune responses in the intestine, and consequently provides an opportunity for other species to benefit from the altered host environment and to establish in and survive for longer than they otherwise might (reviewed by Behnke et al 2001).…”

Heligmosomoides polygyrusreduces infestation ofIxodes ricinusin free-living yellow-necked mice,Apodemus flavicollis

“…We selected Pyrantel pamoate since it is active on gastrointestinal nematodes but is not systemic and does not affect the ectoparasite infestation (Wahid and Behnke, 1996 ;Quinnell, 1992). The mice caught that were not anthelmintic treated, were orally infected with an average number of 30, third-stage infective H. polygyrus larvae to increase nematode abundance (Keymer and Hiorns, 1986 ;Gregory et al 1990). Infective H. polygyrus larvae were obtained from eggs collected from yellow-necked mice faeces from the study area.…”

Population regulation: a dynamic complex of interactions

“…Those numbers are usually regulated in individual hosts by immune responses, as suggested by detailed laboratory studies (e.g. Gregory et al 1990) and by the relatively low numbers of parasites in natural infections compared with very high rates of acquisition by sentinel (tracer) animals (e.g. Gregory 1991).…”