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Causes of Mucus in a Dog's Stool

t's not uncommon to find mucus in your dog's stool, and some of the causes are benign. Learn more about why this occurs and when you should be concerned.

Disclosure- There are images that may be a bit "disgusting's" , but had to use them for educative reasons.

Why Is There Mucus in Your Dog's Stool?

When inspecting your dog's poop, were you surprised to see mucus or something that looked like jelly? The presence of mucus is actually very normal. It's common to see a little bit of a slimy, jelly-like substance in your dog's stool. Glands in the intestinal tract naturally produce mucus to help keep the colon lubricated and moist to help the stools pass along. However, excessive mucus accompanied by blood in the stool, diarrhea, vomiting and/or other symptoms is a cause for concern.

It's always a good idea to inspect a dog's stool to see if there is anything unusual or alarming in it. Your dog's poop can tell you many things, such as what he ate, if he has parasites, if he's stressed out or if he's suffering from some form of digestive disorder. If you find mucus in your dog's stool, you may be wondering where it's coming from and what causes it. In the next paragraphs, we will learn more about it.

When Does Mucus Become a Concern?

  • When there is an excessive amount.

  • When blood is present.

  • When there is vomiting, diarrhea, lethargy and/or loss of appetite.

What Should Mucus Normally Look Like?

Normal mucus often looks like a clear jelly-like substance mixed within the stool. Sometimes, it may envelop the stool like a sausage casing. In some cases, the mucus may also appear white. If you make it a habit to routinely inspect your dog's stools, you'll quickly note when something looks off.

Why Is There Blood in My Dog's Stool?

If your dog is pooping blood but acting normal, then it is likely caused by a sudden change in your dog's diet, stress, food intolerance or dietary indiscretion.

Other serious causes of blood in dog stool include parvovirus, hemorrhagic gastroenteritis and intestinal parasites, which must be diagnosed by a veterinarian.

Call a vet immediately if you see blood along with symptoms of vomiting, chronic diarrhea, dehydration and/or lethargy.

What the Color Indicates

  • If the blood is fresh and bright red, it is derived from the colon or rectum.

  • If you see tarry stool, then the cause likely originates in the upper small intestine.

15 Causes of Mucus in Dog Poop

  1. Stress

  2. Dietary Indiscretion

  3. Food Intolerances

  4. Intoxication

  5. Diet Changes

  6. Inflammatory Bowel Disease (IBD)

  7. Crohn's Disease

  8. Colitis

  9. Presence of Intestinal Parasites/Protozoans

  10. Fungal Infection

  11. Small Intestinal Bacterial Overgrowth (SIBO)

  12. Clostridial Enterotoxicosis

  13. Parvovirus

  14. Ingesting Foreign Objects

  15. Polyps and Tumors of the Intestinal Lining

What Does It Mean If There Is Mucus in Dog Stool?

An increase in mucus is often a symptom of irritable bowel syndrome (IBS), which is an irritation and possible inflammation of the colon or large intestine. When irritated, the intestinal tract decides to create an extra layer of protective mucus lining. Dogs with irritable bowel syndrome will have the urge to defecate frequently and will pass semi-formed feces or runny stool with small amounts of bright, red blood at the end and/or excessive mucus. Following are some potential causes of irritable bowel syndrome.

1. Stress

Believe it or not, a dog's mental and emotional state could have a great impact on his bowel movement. Like humans, dogs under stress or anxiety will have diarrhea, which may include large amounts of mucus and some blood. Other symptoms include having the urge to go frequently or straining when defecating.

If your dog strains and nothing comes out, then it may simply be stress, which gives him the urge to go despite having an empty colon. This is not to be confused with constipation. Most likely, the straining happens after your dog has already defecated several times. Diarrhea due to stress should resolve itself within 24 to 48 hours, so call a vet if it does not. You can prevent bloody diarrhea due to stress by first resolving the source of stress.

Many factors can influence your dog's well-being.

2. Dietary Indiscretion

If your dog is a dumpster diver or a counter surfer, then she probably ate something bad that gave her an upset stomach. This can be easily remedied with a bland diet or slippery elm bark.

3. Food Intolerances

Allergies or intolerances to food will cause an upset stomach that may result in vomiting, flatulence or diarrhea. Common food culprits include dairy, undercooked eggs, raw meat or bones, or fried or greasy foods. Chronic diarrhea may also be a result of eating foods that are toxic to dogs.

4. Intoxication

If you suspect that your dog has ingested poison or toxic foods, such as chocolate, gum or grapes/raisins, then symptoms of vomiting and chronic diarrhea will occur along with more serious signs of poisoning, such as wobbly gait, fatigue, fainting and seizures.

5. Recent Diet Changes

Did you recently switch to another brand of dog food? Sometimes, mucus or liquid feces is simply a sign that your dog's digestive system is trying to adjust to a new diet. If this is the case, introduce the new food slowly by mixing in increasing amounts with some of his old food. If your dog is not experiencing severe diarrhea or constipation and there is no sign of blood, then you can continue feeding the new food.

Your dog should be able to adjust within a week's time, and his stool should return to normal. If not, speak with your veterinarian. You may have to switch to a hypoallergenic food brand.

New foods should be introduced gradually.

6. Inflammatory Bowel Disease (IBD)

Inflammatory bowel disease is a condition in which the intestine is chronically attacked by inflammatory cells. The most common type of IBD is characterized by an infiltration of lymphocytes and plasmacytes cells. This is common in German Shepherd and Shar Pei dogs. The second most common form involves the eosinophils cell.

7. Crohn's Disease

Also know as granulomatous colitis or regional enteritis, Crohn's disease is a chronic form of IBD. The first symptoms of Crohn's disease will be loose stool and a frequent urge to defecate. The stool may also contain bloody mucus. If the disease progresses, you will notice your dog becoming a picky eater, losing his appetite and losing weight.

8. Colitis

Large bowel diarrhea is often associated with colitis. You may also see straining (not to be confused with constipation) and small amounts of blood and excessive amounts of mucus. Stress is usually the leading cause, but colitis could also be brought on by an infection or parasites.

Histiocytic ulcerative colitis is a rare disease in which ulcers line the colon and cause inflammation with periodic acid-Schiff (PAS) positive histiocytes. If your dog has ulcerative colitis, you will see a lot of blood in his stool.

9. Presence of Parasites/Protozoans

Whipworms or tapeworms are parasites that live in the intestine and colon and cause severe irritation. They are some of the most pathogenic worms found in dogs and can be ingested via food, soil or water. If this is the cause of your dog's diarrhea, you may be able to find whipworm eggs in the stool.

Giardiasis is an intestinal infection caused by the protozoan parasite, giardia. This parasite is usually ingested from another animal's feces, including human feces. Dogs with giardiasis will exhibit foul-smelling diarrhea that is watery, frothy and contains a lot of mucus.

Dogs can contract whipworm by ingesting feces, so make sure to keep your yard clean.

10. Fungal Infection

Histoplasmosis is a fungal infection that is contracted by eating or inhaling contaminated soil or bird droppings. Symptoms include loss of appetite and diarrhea with straining.

11. Small Intestinal Bacterial Overgrowth (SIBO)

SIBO occurs when the dog's body, for whatever reason, is unable to absorb raw food, so the bacteria already present in the dog's intestine eats the undigested food and uses it as fuel to grow and overpopulate. This causes an imbalance of good colon bacteria. SIBO is commonly seen in dogs with exocrine pancreatic insufficiency (EPI). German Shepherds are overrepresented in those who suffer from this disease. Symptoms include yellow mucus, loose/soft stool, mucus coating on the stool, flatulence, chronic diarrhea, crankiness and lethargy.

If the mucus in your dog's stools is caused by an imbalance of bacteria, Fortiflora is a probiotic that can help restore that balance.

12. Clostridial Enterotoxicosis

This disease is also characterized by an overgrowth of bacteria. The bacteria is usually acquired through raw meats and vegetables or decaying foods. Dogs with clostridial enteroxtoxicosis may experience diarrhea with a shiny mucus coating, frequent and watery stools, stomach discomfort and straining


13. Parvovirus

This is a highly contagious viral disease that attacks the intestinal tract. The symptoms of parvo are lethargy, severe vomiting, bloody diarrhea, loss of appetite and life-threatening dehydration. Puppies, Parvo can be confused with other gastrointestinal situations. Adolescent dogs and unvaccinated dogs are the most susceptible. Breeds at risk include Rottweilers, Dobermans and German Shepherds. If your puppy is infected,

14. Ingesting Foreign Objects

If your dog has an appetite for non-food items, it could explain why he has digestive problems. This medical condition is known as pica and could be a symptom of a greater problem, such as malnutrition. But, most of the time, it is just a bad habit that must be stopped through training. If you're not sure whether your dog has swallowed something he shouldn't have, check for these major signs of intestinal blockage.

Check whether your dog might've eaten something he shouldn't have.

15. Polyps and Tumors of the Intestinal Lining

If you see rectal bleeding, it may indicate that polyps or tumors have grown inside your dog's intestinal lining or digestive tract. Please see a veterinarian as soon as possible if there is blood in the stool.

Treatment for Mucus in Dog Stool

Because some causes of mucus in stool can be serious, it's best to see a vet, especially if the dog has other symptoms such as diarrhea, vomiting, bloody stools, abdominal pain, fever or lethargy.

Why You Should See a Vet

Seeing the vet is useful because, through diagnostic tests, he/she can most likely pinpoint the problem and provide you with a solution to prevent the problem from recurring. In the case of parasites, the appropriate dewormer should kill all parasites and take care of all the associated gastrointestinal problems. Surgery may be needed if there is intestinal blockage or a polyp. Dogs with food intolerance may benefit from a hypoallergenic diet.

When It's Okay to Wait

In some cases, the episode of mucus in stool will be short lived, and the dog's stool will return to normal after a few days. If it's caused by a dietary indiscretion or a recent diet change, fasting and feeding a bland diet for a few days may help. Probiotics or yogurts containing live culture are also helpful for replenishing helpful flora to the gut. In mild cases, Imodium can be used under the guidance of your vet.

However, if your dog has other accompanying symptoms, and you suspect he might have gotten into something toxic, you should play it safe and see your vet promptly.

Why You Should Regularly Examine Your Dog's Stool

Welcome to the poop inspection club! I learned just how important the appearance of dog stool is while working for a veterinarian's office and working alongside vets in shelters. Dog owners used to drop off many stool samples and specimens of parasites they found. I quickly learned what the signs of trouble looked like. Now that I board and train dogs, I always check to see what their stools look like so that I can report any unusual appearances to their owners and take the dog to the vet if needed.

Yearly Fecal Exams Are Recommended

I recommend dog owners do the same, but don't rely on visual inspections alone. Dog owners sometimes tell me, "Oh, I know my dog is free of parasites because I look at his stools every day." Healthy-looking stools may be misleading, as there are many things the eyes can't see. For good reason, vets use microscopes to thoroughly inspect what's really in there. Yearly fecal exams are always recommended to keep things in check.