Dogs and cats that are affected mildly generally are bright, alert and do not appear to be sick, except for the diarrhea. Animals that are affected more severely can be vomiting, depressed, dehydrated, listless, have an increased frequency of diarrhea, and may even have blood in the stool.
Animals with small bowel diarrhea typically pass a larger volume of feces. They defecate two to four times a day, lose weight, occasionally have melena, flatulence and borborygmus, and occasionally vomit. Cats may have tenesmus or dyschezia.
Dogs with large bowel diarrhea pass a smaller volume of feces each time, but defecate more frequently, about four times a day. There may be minimal to no weight loss, but there can be hematochezia and mucus with occasional dyschezia and tenesmus, and an urgency to defecate. Vomiting is uncommon.
