Nutritional Ecology and Digestive Responses of an Omnivorous-Insectivorous Rodent (Abrothrix longipilis) Feeding on Fungus

Abstract

Spore retention by the digestive tract of mycophagous rodents may affect the temporal and spatial dynamics of spore dispersal; rodents may also benefit from consuming a discrete resource rich in minerals and vitamins. Some research suggests that hypogeous fungi are not a nutritionally high-quality food item for small rodents, regardless of being highly consumed by these small mammals. Fungi may be a valuable dietary item when higher-quality food is in low abundance. However, the extent to which fungi are incorporated into diet will ultimately depend on the physiological capacities of organisms for digesting such a resource. Here we investigate digestibility of fungus compared with insects and young foliage of plants, and we draw inferences about digestive constraints in a forestdwelling, mycophagous, habitat-generalist rodent (Abrothrix longipilis) exploiting different diets. We show that the fruiting bodies of fungi are less digestible than young leaves of plants and insects. The intake of fungus, in gra...