Leaf swallowing and parasitic infection of the Chinese lesser civet Viverricula indica in northeastern Taiwan

Abstract

[Background]Ingestion of plant parts purportedly for their non-nutritive and/or bioactive properties has been widely reported across the animal kingdom. Many of these examples are viewed as behavioral strategies to maintain health by controlling the level of parasite infections. One such behavior is leaf swallowing, the folding and swallowing of whole leaves without chewing. Void of any nutritional benefit, defecation of the whole leaves is associated with the physical expulsion of intestinal parasites. Fecal samples of the Chinese lesser civet Viverricula indica were collected along a fixed transect line monthly for 17 months in the Fushan Experimental Forest, northeastern Taiwan. We inspected samples for the occurrence of undigested leaves and parasite worms to test the possible antiparasitic function of the behavior in this species.[Results]Of the collected feces, 14.3%contained whole, folded, undigested leaves of grass. The co-occurrence of undigested grass and Toxocara paradoxura worms in the feces was statistically significant. Adult worms of T. paradoxura were trapped inside the fecal-grass mass or on the surface of leaves in these samples. Increases in the T. paradoxura prevalence and infection intensity were associated with a higher presence of whole leaves in the feces.[Conclusions]Reported for the first time in the context of self-medication for civet species, we propose that swallowing grass may facilitate expulsion of adult worms of T. paradoxura, which resembles behaviors widely reported in African great apes, bears, and geese.