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What’s in a Stool?

The WORLD, Jan/Feb 1999 Vol. VI Issue 1

by by Lynn Roberts, DVM
Topics: Health

Can looking at the stools of animals give us a clue to possible disease? Yes! Small animal stools (I will deal with dogs and cats in this issue) can vary dramatically in color, consistency and volume. Diets can have a big impact on what stools in most dogs and cats look like. However, most dog and cat stools should be brown (light to dark, depending on diet) and formed (not too loose or too hard).


Most worms and other parasites cannot be seen in animals’ stools. The majority of worms and parasites live in the dog’s or cat’s intestines. Most worms produce eggs that are shed in the feces, but they are microscopic. It requires examination of the feces under a microscope to identify the eggs of individual worms. An exception to this would be tapeworms and, occasionally, roundworms. Tapeworms segment off in the intestines, and the segments look like flat white rice in the stool. These segments can also be found around the anus or attached to the fur around the anus. Roundworms can occasionally be passed in the stool. These worms look like strands of spaghetti.


Fresh red blood in the stool with or without mucous (clear and jelly-like substance) generally indicates a colon (or large intestine) problem. These dogs generally continue to eat well and do not vomit, but diarrhea is usually present. Possible causes of large intestine problems include whipworms, colitis (bacterial or spastic), allergies, inflammatory bowel disease or possible colon cancer.


Dark, tarry-like stools with or without diarrhea indicate bleeding in the stomach or small intestines. The blood appears black and tarry (sticky) because the blood has been digested. These dogs are usually vomiting, experience some weight loss and/or dehydration. Possible causes of stomach or small intestine problems include parasites, bacterial or viral diseases, pancreatitis, inflammatory bowel disease, stomach ulcers, milk intolerance, cancer and others.


Excessively hard, firm or dry feces may be an indication of constipation in dogs and cats. It can be useful to break these stools up and look for hair, bones, rocks or sand. Finding an underlying cause for the constipation can provide an easy treatment for these animals (i.e. hair ball lubricants or removing source in the case of rocks, sand or bones).


Other less-common stool changes to be aware of include gray or chalky stools and stools with excessive amounts of fat in them. Stools that are gray or chalky white may indicate a liver problem. Stools that have excessive amounts of fatty material in them (high volume, very foul odor, and greasy), accompanied by large amounts of flatulence may indicate pancreatic digestive enzyme deficiencies.


When walking dogs or changing litter boxes, pay attention to those stools. You may be able to clue your clients into a problem with their pet that they may have not noticed.


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