Liver Disease – Fatty Liver Syndrome in Cats

What is Fatty Liver Syndrome and how does a cat get it?

Feline Fatty Liver Syndrome (FLS) is also known as feline hepatic lipidosis. This disease is unique to cats and is one of the most common liver diseases seen in cats.

"The chances of FLS occurring are greater if the cat was overweight or obese."

liver_disease1Usually a cat with FLS has recently gone through a period of anorexia (little or no eating) for three to four consecutive days. The chances of FLS occurring are greater if the cat was overweight or obese before the anorexia began. When fat is broken down rapidly to supply energy and nutrients to the anorectic cat, it can overwhelm the ability of the liver to process it. This fat becomes stored in and around the liver cells, further compromising liver function. The cat usually becomes icteric or jaundiced, as evidenced by a yellow color in the whites of the eyes or in the skin. At this point, the disease will be fatal if not treated rapidly and aggressively.

How is FLS diagnosed?

Diagnosis of FLS is made from blood tests that demonstrate poor liver function and from a liver biopsy or aspirate. The latter may be performed during an exploratory surgery or by inserting a needle into the liver through the skin. The liver sample is sent to a veterinary pathologist for analysis. A cat with FLS will have a large amount of fat in and among the liver cells. Other diagnostic tests may be performed in an effort to determine why the cat originally stopped eating. If the cause for anorexia is treatable or resolved, the prognosis is reasonably good.

Is this a treatable disease?

"This disease is treatable with aggressive nutritional support until a normal appetite returns."

This disease is treatable with aggressive nutritional support until a normal appetite returns. A consistently high level of nutritional support is required for the liver to resume functioning so it may mobilize the excessive fat stores. This takes an average of six to seven weeks. Therefore, a method of feeding must be used that allows you to feed your cat at home.

How do I provide the necessary nutritional support?

A feeding tube is surgically implanted into your cat so you can syringe feed a special diet through the feeding tube into the stomach. The feeding tube may be placed into the esophagus or the stomach (see our handouts "Tube feeding in cats", "Esophagostomy tube feeding" and "Gastrostomy tube feeding" for further information). Your veterinarian will determine the best one to use with your cat, depending on the particular circumstances.

You will need to use a syringe to feed your cat a special food mixture through the feeding tube three to five times per day. This food is formulated to meet the cat's nutritional needs; it should not cause vomiting or diarrhea. To feed your cat, follow these steps:

  • Place the following ingredients in a blender and run it at the fastest speed until the food is uniformly mixed. After mixing, pour the food through a kitchen strainer to remove any remaining clumps.

1 can (15 oz) of a high quality feline growth food +

10 oz of water +

2 oz of vegetable oil  +

8 potassium chloride tablets.



  • Remove the cap from the feeding tube.
  • Using the syringe provided, inject ________ cc of the blended food into your cat's feeding tube. Feed your cat _____ times per day FOR A TOTAL OF _________ cc PER 24 HOURS. It is helpful to inject the food slowly, about 1 cc per second, and to elevate your cat's front feet so the food goes easily into the stomach.
  • After the food has been injected, inject 5-10 cc of tap water through the tube to flush any remaining food and prevent clogging. Replace the cap in the tube.
  • Any remaining food should be stored in the refrigerator. Before the next feeding, it should be warmed to body temperature under hot tap water or in a microwave oven. If you heat it in a microwave oven, be sure to mix the contents thoroughly prior to feeding because of the potential for uneven heating. Also, always check the temperature prior to feeding to be sure that the food is not too hot by placing food on the back of your hand.

NOTE:  Technically, a cubic centimeter (cc) and a milliliter (ml) are slightly different. However, for our purposes, a cc is the same as a ml. Syringes are often marked in cc's.

When is the tube removed?

"At least once weekly, offer your cat a small amount of its favorite food by mouth so that you will know when its appetite returns."

The average cat requires six to seven weeks of tube feeding before it begins to eat on its own after an episode of FLS. At least once weekly, offer your cat a small amount of its favorite food by mouth so that you will know when its appetite returns. The feeding tube will not hinder eating in any way. After your cat has been eating well for three to four days, it should be returned to the hospital for tube removal. Removal of the tube is simple and does not require anesthesia; however, you should not attempt to remove the tube yourself.

Related Tags

liver, feeding, food, disease, cats, syndrome, fatty, feline, nutritional, feed, appetite, eating, anorexia, obese, lipidosis

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