Bloated or Pot Belly in Kittens

A pot belly is a swollen or enlarged belly that can be alarming to the cat’s caregiver. But what does it mean and is it normal for a kitten to have a pot belly?

When is a bloated or pot belly normal?

Kittens have tiny tummies and require multiple meals a day. After a meal, it is normal for a kitten to have a pronounced belly but this will go down quickly and in the absence of other symptoms (listed below).

Causes of bloated belly in kittens


Kitten with a pot belly due to roundworms
Pot belly on a kitten due to heavy roundworm infection. Image Natsicha Wetchasart, Shutterstock

Roundworms infection is a common cause of a pot-bellied appearance in kittens. Two species infect cats, Toxocara cati and Toxascaris leonina. Infection with T. cati is most common in cats.

Roundworms feed upon the intestinal contents, competing with the host for food. They are around 3 – 5 inches long with a spaghetti-like in appearance. Both T. cati and T. leonina are found throughout the world.

Roundworm infection is called toxocariasis.

The most common source of infection in kittens is via the mother’s milk (transmammary infection) which is detailed below.


  • Direct ingestion (ingestion of eggs via contaminated food, feces, water and environment)
  • Transport hosts (ingestion of infected rodents) which is an unlikely source of infection in kittens.
  • Transmammary infection (via the mother milk). As we know, roundworms encyst in the tissues of older kittens and adults. Pregnancy can reactivate larvae that migrate to the mammary glands and infect nursing kittens.

Once consumed, the larvae hatch from the egg and can behave in one of two ways.

  1. In young kittens, the larvae migrate through the intestinal wall and into the circulatory system, passing through the liver where it molts into stage three larvae (L3) and into the windpipe (trachea) where they are coughed up and swallowed, finally taking up residence in the cat’s small intestines where they reach sexual maturity and begin to produce eggs which are shed in the feces where it develops in the environment into the infectious stage containing second-stage larvae (L2).
  2. If an older kitten or adult ingests an infective egg, the larvae hatch and migrate to organs and muscles where they encyst and become dormant. Some can migrate back to the small intestine, mature and produce eggs. Others remain dormant until activated by pregnancy.


  • Dull coat
  • Presence of worms in the vomit or feces (heavy infestations)
  • Diarrhea
  • Pot-bellied appearance, especially in kittens
  • Coughing (due to roundworm migration through lungs)
  • Fatigue
  • Stunted growth
  • Loss of appetite
  • Severe infestations can lead to pneumonia and intestinal and bowel blockage


Treatment of roundworm is straightforward, several topical products, pastes, chews, and tablets are available to treat roundworm in kittens and cats. All cats need to be wormed, even those kept indoors.

Kitten worming schedule:

  • Every 2 weeks from 2 weeks of age until 12 weeks of age.
  • Once a month from 12 weeks of age until 6 months.
  • Every three months from 6 months.

Food intolerance

Food intolerance is an adverse reaction to food, one of its ingredients or additives. It differs from a food allergy in that there is no immune system involvement. Food allergies typically cause nonseasonal itching, especially around the head and face, swollen and inflamed areas on the face and ears, hair loss due to itching, vomiting, and diarrhea.

A common food intolerance that many people have heard of is milk. This is because older kittens and adult mammals lack the enzyme necessary to digest lactose, which is the major sugar in milk.


  • Flatulence
  • Bloating
  • Abdominal pain
  • Diarrhea


Avoidance of the food where possible. Once weaned, kittens and adult cats have no nutritional requirement for milk. If milk is not the culprit, it will be necessary to rule out other possible ingredients and the veterinarian may recommend a food elimination trial, in which the kitten is fed one type of food (hypoallergenic), to see if symptoms resolve. If they do, the cat is then challenged, by re-introducing it to its normal food to see if symptoms return.

Note: All young kittens MUST have milk to survive. The weaning process begins around 4-5 weeks of age, but before that, their only source of nutrition is milk. It is extremely important that you do not give a young kitten cow’s milk. The best possible milk is from the kitten’s mother. If the kitten is orphaned and a foster mother can’t be found for the kitten then the kitten will need to be given a specially designed kitten formula, which can be purchased from your veterinarian. Cow’s milk is fine for baby cows, but it is not suitable for kittens.

Feline infectious peritonitis

FIP is a fatal viral disease caused when the coronavirus, a common and mostly harmless virus in cats, mutates to a virulent form or an aberration of the immune response occurs. Kittens are at the greatest risk of developing FIP.

FIP comes in two forms, dry and wet. Wet FIP causes a build-up of fluid in the abdominal cavity.


  • Abdominal bloating due to fluid accumulation
  • Difficulty breathing
  • Fever
  • Depression
  • Poor coat condition
  • Loss of appetite


FIP is almost always fatal and there is no effective cure at this time. Supportive care and treatment may be provided, but this is a short term solution, and most cats will succumb to the disease.

Intestinal blockage

An intestinal blockage can occur anywhere along the cat’s gastrointestinal tract. Common causes include an ingested foreign object, heavy roundworm or tapeworm infection, twisting of the intestine, telescoping of the intestines and adhesions.

Intestinal obstructions are common in kittens who begin to explore their environment from a few weeks old. Just like human toddlers curiosity can get the better of them and they can chew on lots of things that aren’t cat-friendly such as elastic bands and hair elastics.


  • Vomiting
  • Diarrhea or a complete absence of defecation
  • Swollen and painful abdomen
  • Loss of appetite
  • Hunched over appearance
  • Lethargy


Most cases of gastrointestinal obstruction require surgery. That includes tumours, hernias, twisted or telescoped intestines, ingestion of foreign object and pyloric stenosis.

  • Endoscopy to stretch strictures. If scarring has occurred, surgical removal of the affected portion will be necessary.
  • Surgical removal of dead intestinal tissue.
  • Anti-worming medication to treat tapeworm.


Constipation is the infrequent passage of hard and dry stools. There is no set number of bowel movements a cat must take in a day, but one to two is average. There are many causes of constipation which include dehydration, congenital defects (Manx syndrome, imperforate anus), obstruction, dietary (not enough fibre in the diet), neurological disorders, certain drugs, pelvic abnormalities, a mother cat or carer who does not stimulate the young kitten to defecate, and idiopathic (no known cause).


  • Painful defecation, straining to pass a stool
  • Small, firm feces which may contain blood or streaks of blood
  • Crying in the litter tray
  • Frequent genital licking
  • Abdominal pain
  • Swollen belly
  • Lethargy
  • Hunched over appearance
  • Vomiting
  • Decreased appetite


The goal of treatment is to address the underlying cause where possible. In addition, it is necessary to treat constipation which, can include:

Stool softeners, laxatives, and increasing water consumption. Severely constipated kittens will need veterinary intervention.

  • Enema or manual extraction of the feces.
  • Rehydration with intravenous fluids.

Toxic milk syndrome

Toxic milk syndrome is a life-threatening condition in which kittens develop septicemia (bacterial infection of the blood) due to an infection in the mother (such as mastitis or pyometra), which reaches the milk, or contaminated kitten replacement milk. Kittens between 0-2 weeks are most commonly affected.


  • Failure to thrive
  • Bloating
  • Diarrhea
  • Listlessness
  • Crying kittens


Do not allow kittens to nurse from the mother if she has septic mastitis, it will be necessary to bottle feed them with a suitable kitten milk formula. Always sterilise bottles and wash hands thoroughly before feeding kittens. Discard unused milk.

Fluids will be necessary for severely dehydrated kittens.

The mother and kittens will be put on a course of antibiotics to treat the infection.

Feature image: SunRay BRI Cattery RU, Shutterstock


  • Julia Wilson, 'Cat World' Founder

    Julia Wilson is the founder of Cat-World, and has researched and written over 1,000 articles about cats. She is a cat expert with over 20 years of experience writing about a wide range of cat topics, with a special interest in cat health, welfare and preventative care. Julia lives in Sydney with her family, four cats and two dogs. Full author bio

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