The microbial flora in the gastrointestinal tract.
D000375:Aging; D000818:Animals; D000831:Animals, Newborn; D001831:Body Temperature; D002415:Cats; D002417:Cattle; D002645:Chickens; D004064:Digestive System / Q000382:microbiology*; D004285:Dogs; D005502:Food; D005769:Gastrointestinal Motility; D006801:Humans; D051379:Mice; D051381:Rats; D013045:Species Specificity