Physiological and morphological responses to simultaneous cold exposure and parasite infection by wild-derived house mice
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- 1Many animals respond to environmental demands with phenotypic plasticity of morphology and physiology. We examined the effects of ambient temperature and parasitism on morphology and physiology of wild-derived house mice (Mus musculus) that were exposed to cold and/or experimentally infected with a naturally occurring intestinal nematode (Heligmosomoides polygyrus).
- 2Parasitized mice had changes in some organ masses, decreased ability to digest food, and lower rates of glucose transport but similar total glucose transport capacity as unparasitized mice. Wild-derived house mice did not use fat stores to respond to parasitism but did increase mucosal mass in the small intestine enough to maintain glucose acquisition at a similar level to unparasitized mice.
- 3Cold-exposed mice showed increased masses of some organs, lower rates of glucose transport but similar total capacity to transport glucose as warm acclimated mice.
- 4The effects of cold exposure and parasite infection were largely independent of each other for the morphological and physiological parameters we measured.
- 5The more recent exposure of wild-derived house mice to fluctuating temperatures and to parasite infection may help to explain the subtle differences that we observed in how wild-derived mice respond to environmental demands compared to their laboratory mouse counterparts.