A preliminary note on the intestinal parasites of wild chimpanzees in the Mahale Mountains,Tanzania

Feces of wild chimpanzees in the Mahale Mountains, Tanzania, were inspected for intestinal parasites under a compound microscope. Eggs or larvae ofOesophagostomum, Strongyloides, Trichuris, Prosthenorchis, andBertiella were found. Intestinal nematodes significantly increased in the mid-rainy season. This finding supports (or, at least, is not in conflict with) the hypothesis thatAspilia leaves which are occasionally swallowed by chimpanzees may function as a vermicide, since ingestion of such leaves also increases significantly in the mid-rainy season.