Colitis is inflammation of the colon (large intestine). It can be either acute (lasting only a few days) or chronic (lasting for weeks).


Immature coccidian, called oocysts, are passed in the stool of an infected dog. They survive for a long time and mature on the ground. If an animal swallows the matured oocysts, they mature even further in the animal’s intestine.

Causes of infection include:

  • Eating contaminated ground
  • Eating an infected mouse
  • Babies nursing from an infected mother
  • Animals less than 6 months have no immunity to coccidia, and can get the disease from other infected puppies

In kennels, animal shelters, and breeding facilities, infected animals should be isolated.


The main symptom of colitis is frequent diarrhea with mucus or blood. This is because colitis causes the body not to be able to absorb water properly. The body cannot either store feces in the colon.

Other signs may include:

  • Straining during and after defecation
  • Cramping
  • Gas
  • Sudden urgency for a bathroom

You may also notice vomiting and weight loss, but only rarely.


Your veterinarian will:

  • Review your pet’s medical history
  • Perform a physical exam (with focus on the rectal and abdominal areas)
  • Take a colon biopsy

Your veterinarian may do other teststo rule out other conditions, including:

  • Stool sample
  • Cytology (a study of the structure and function of your dog’s cells)
  • Blood tests
  • Urine tests
  • X-rays, ultrasound


Most cases of colitis cannot be cured. However, you can manage your dog’s colitis with a special diet and medicine that your veterinarian may prescribe.

Diet: You should feed with pet easily digested foods that are high in fiber. Many dogs will have to remain on this diet for life.

Medication: The exact medication depends on the cause of the colitis:

  • Antibiotics: to control bacterial causes
  • Sulfa-containing drugs: to control chronic colitis
  • Immunosuppressive drugs: for colitis caused by immune deficiencies
  • Steroids or other anti-inflammatory medications


There is no way to know beforehand which dog might develop colitis. Once a pet is susceptible, you can prevent flare-ups with a bland and easily digested diet that is high in fiber.


In most cases, there is an excellent prognosis with a change in diet and some medication. You can manage your pet’s colitis to the point where it can live a happy, comfortable life for many years.

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