title: Effect of the abrasive properties of sedges on the intestinal absorptive surface and resting metabolic rate of root voles.
abstract: Recent studies on grasses and sedges suggest that the induction of a mechanism reducing digestibility of plant tissues in response to herbivore damage may drive rodent population cycles. This defence mechanism seems to rely on the abrasive properties of ingested plants. However, the underlying mechanism has not been demonstrated in small wild herbivores. Therefore, we carried out an experiment in which we determined the joint effect of abrasive sedge components on the histological structure of small intestine as well as resting metabolic rate (RMR) of the root vole (Microtus oeconomus). Histological examination revealed that voles fed with a sedge-dominated diet had shorter villi composed from narrower enterocytes in duodenum, jejunum and ileum. Reduction in the height of villi decreased along the small intestine. Activity of the mucus secretion increased along the small intestine and was significantly higher in the ileum. The intestinal abrasion exceeded the compensatory capabilities of voles, which responded to a sedge-dominated diet by a reduction of body mass and a concomitant decrease in whole body RMR. These results explain the inverse association between body mass and the probability of winter survival observed in voles inhabiting homogenous sedge wetlands.
authors.affiliation: Mammal Research Institute Polish Academy of Sciences, 17-230 Białowieża, Poland mwieczorek@ibs.bialowieza.pl.
authors.forename: Monika
authors.initials: M
authors.lastname: Wieczorek
authors.affiliation: Mammal Research Institute Polish Academy of Sciences, 17-230 Białowieża, Poland.
authors.forename: Paulina A
authors.initials: PA
authors.lastname: Szafrańska
authors.affiliation: Institute of Environmental Sciences, Jagiellonian University, 30-387 Kraków, Poland.
authors.forename: Anna Maria
authors.initials: AM
authors.lastname: Labecka
authors.affiliation: Max Planck Institute for Ornithology, 78315 Radolfzell, Germany Department of Biology, University of Konstanz, 78464 Konstanz, Germany.
authors.forename: Javier
authors.initials: J
authors.lastname: Lázaro
authors.affiliation: Institute of Biology, University of Białystok, 15-097 Białystok, Poland.
authors.forename: Marek
authors.initials: M
authors.lastname: Konarzewski
mesh_terms: D000818:Animals; D003411:Arvicolinae / Q000502:physiology*; D001481:Basal Metabolism; D001835:Body Weight; D031255:Carex Plant / Q000009:adverse effects; D004032:Diet / Q000009:adverse effects; D020895:Enterocytes; D007413:Intestinal Mucosa / Q000378:metabolism / Q000502:physiology*; D007421:Intestine, Small / Q000033:anatomy & histology* / Q000502:physiology
keywords: Body mass; Plant defensive mechanism; Sedges; Silicon; Small intestine