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This information is provided by Provet for educational purposes only.

You should seek the advice of your veterinarian if your pet is ill as only he or she can correctly advise on the diagnosis and recommend the treatment that is most appropriate for your pet.

Swelling of the abdomen can be caused by many of which is ascites (or dropsy), but what is this ?

There are many potential causes of apparent swelling or distension of the abdomen , giving the animal a pot-bellied appearance, including :

  • Pregnancy
  • Obesity
  • A large abdominal mass (eg an enlarged liver, or a cancer)
  • A large worm burden (especially in young puppies and kittens)
  • Weakening of the abdominal muscles leading to a pendulous abdomen (eg as occurs in Cushing's Syndrome)
  • The presence of free fluid in the abdominal (peritoneal) cavity

Quite a large volume of fluid is needed to cause visible distension of the abdominal wall and this fluid can take several forms including :

  • Clear, watery fluid due to oedema - this is true ascites
  • Urine - eg if the bladder is ruptured
  • Fluid produced as a result of inflammation - eg as occurs in peritonitis

What causes this accumulation of watery fluid  in the abdomen, called ascites ?

Ascites is NOT caused by :

  • Drinking too much water
  • Eating too much salt
  • High blood pressure

Ascites IS caused by several disorders including :

  • Low concentrations of protein (albumin) in the bloodstream. This can occur :
    • If there are massive losses of protein from the body due to kidney disease
    • If there are massive losses of protein from the body due to gastrointestinal disease
    • In starvation
  • Obstruction to normal blood circulation e.g. liver disease
  • Poor circulation - as occurs in heart failure

A diagnosis of free fluid in the abdomen can be made by physical examination of the animal and on X-rays or Ultrasound, but a definite diagnosis of ascites can only be confirmed by laboratory analysis of a sample of the fluid.

Treatment of ascites involves treating the underlying cause (eg heart disease) and removing the excess fluid from the abdomen. The fluid can usually be removed by using drugs (diuretics) and/or by reducing salt intake. Large volumes of fluid can cause considerable pressure on organs within the abdomen, so sometimes the fluid is surgically drained.

Last updated : March 2008