A dog that is experiencing colitis will usually display a noticeably soft, watery bowel movement when they defecate. However, this symptom alone is not necessarily indicative of Colitis, since it may be a symptom of a temporary gastrointestinal condition, as well as several other medical conditions that involve the gastrointestinal tract.
Most dogs that are affected by colitis will experience chronic, noticeable diarrhea. This will
usually be present over an extended period of time. Diarrhea is characterized by loose, inconsistent
bowel movements, which may occasionally manifest entirely as a liquid waste substance. As
with many of the other symptoms of Colitis in dogs, diarrhea alone is not a positive indication
of Colitis.
Diarrhea is a symptom that is present with many other medical conditions, such as parasitic infections,
viral infections, and several others. However, chronic diarrhea is usually indicative of a health
problem, and should be reason enough to seek veterinary attention as soon as possible.
In many cases, dogs with colitis will pass bowel movements more frequently than is normal for a healthy dog. This will be evident, since a dog may whine to be let outside more often than usual. If your dog is kept primarily outdoors, you may see them assuming the "pooping" pose (back legs squatted, tail up) on a regular basis. Since it may be difficult to distinguish between a "normal" number of bowel movements and an "excessive" number, it may be easiest to first identify other symptoms of Colitis.
When passing a bowel movement, dogs with Colitis will usually have significant difficulty in producing stool. This may or may not be accompanied by other symptoms, since it may be difficult to recognize diarrhea or loose stools in a dog that may not be able to produce a bowel movement. In many cases, this symptom will be accompanied by noticeably frequent bowel movements. If your dog is attempting to make bowel movements on a regular basis, but is only able to produce a small amount of stool (or none at all), you will need to seek veterinary attention immediately.
Many dogs with Colitis will experience a gradual (but noticeable) loss of body weight. This occurs most frequently over a period of time, though may accelerate if not recognized. This may be accompanied by secondary symptoms, such as hair loss, malnutrition, and lethargy.