Mucus in dog stool: The common causes

Amy Aitman
June 23, 2017

You'd do anything for your dog, even check his stool, especially if you thought something could be wrong. Notice any differences in your dog's bowel movements lately? Although mucus in dog stool is very common, and necessary, sometimes it warrants a trip to the veterinarian.

What is mucus in dog stool?

Dog stool often has mucus. It's a slime-like substance made by the intestines to keep the lining of the colon lubricated and moist and is perfectly healthy. In fact, small amounts are often dead cells acting as a natural lubricant in the gut, helping prevent constipation. 

"Without it, defecating is much more strained and difficult," says Dr. Krista Magnifico, a veterinarian at Jarrettsville Veterinary Center and the founder of Pawbly. Dr. Kimberly Hammer, a veterinarian at NorthStar VETS and a diplomat of the American College of Veterinary Internal Medicine, agrees that mucus in stool is normal. "Mucus is often either the dead cells being shed from the lining from the colon or secretion from the colon and is usually not a concern," she says.

When is it a problem for your dog?

"Part of being a really great and responsible pet parent means you really need to know what is going into and out of your dog," says Dr. Magnifico. And that means knowing not just what you are feeding him, but what he found to ingest all on his own. Think your dog's mucus is problematic?

Here's when you should call the vet:

  • Your dog has diarrhea
    Both vets say when mucus is accompanied by diarrhea, it's something that could warrant a trip to the vet. "When your dog has diarrhea that persists longer than 24 hours, and is accompanied by mucus in the stool, you should go see your vet," says Dr. Hammer.
  • Any part of the stool is changing
    "If you've suddenly got really, really soft stool and a lot of mucus, or a lot of mucus and not very much stool, that could indicate that there is a problem," says Dr. Magnifico.
  • You witness a change of color
    "The mucus will only change color when there is something else present in it. So, if there's excessive bile or blood, this will change the color of the mucus and could mean something is wrong," says Dr. Magnifico.
  • Your dog is only producing mucus
    When you see your dog overly straining, and nothing is coming out but mucus, this could mean something is wrong in the GI tract. Both veterinarians agree you need to see a pattern of this occurring before taking your dog to see a vet. "The cell turnover in the gut is so rapid and changes quickly, " says Dr. Magnifico. You should wait it out. Dr. Hammer agrees, "If your dog is only producing mucus in a 24-hour time period, it is time to call the vet."
  • Your dog isn't eating or drinking
    "A lot of times dogs will get better with conservative measures at home," explains Dr. Hammer. "Sometimes it can be a bland diet that helps, but if your pet is not eating or drinking, this can be another warning sign that something is wrong." Dr. Hammer warns that if your pet is not drinking anything, don't wait 24 hours to see improvements, especially if you notice other symptoms of lethargy. Just call your vet.

Talking to your dog sitter

If you're worried about the state of your dog's GI tract and health, talk to your dog sitter or dog walker. Make sure he or she keeps track of everything your dog is ingesting, whether it's the food given to the dog directly or a piece of pizza he found on the sidewalk.

You're not with your dog all day and can't tell if she's been straining to poop and just getting mucus, but your pet sitter probably can. Tell your pet sitter or dog walker your concerns and make sure he or she watches your dog closely during the time with your pet. With these precautions, soon your only poo concern will be scooping it off the ground.

And read Dog Vomiting Bile: A Diet Plan for Getting Your Dog Back to Normal.

Amy Aitman is a freelance writer with a passion for the four-legged creatures in this world, especially her 13-year-old Westie, Buckles.

* This article is for general informational purposes only. It is not intended nor implied to be providing medical advice and is not a substitute for such advice. The reader should always consult a health care provider concerning any medical condition or treatment plan. Neither nor the author assumes any responsibility or liability with respect to use of any information contained herein.

Tips and stories from parents and caregivers who’ve been there.

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