Feline Liver Disease
The liver is made up of millions
of cells called hepatocytes. Digested food products arrive at
the liver from the small intestine. They travel via the Hepatic
portal vein. The liver has a large storage capacity and excellent
The liver carries out approximately
1500 functions including:
• Removal of toxins and nitrogen
• storage of iron, fats and vitamins
• regulation of body heat
• production of bile, plasma proteins, vitamins
• metabolises proteins and fats
• changes glycogen to glucose when energy is needed
• destroys old red blood cells
Common Liver Diseases in
(1) Feline Hepatic Lipidosis
(2) Portosystemic shunt
(3) Cholangitis (inflammation of the biliary ducts)
(4) Cholangiohepatitis (inflammation of the biliary ducts and
(5) Portal hypertension (increase in blood pressure in the portal
(6) Bile duct obstruction
(7) Chronic Hepatitis and cirrhosis
Early signs of liver disease
vomiting, weight loss, pyrexia (fever), no jaundice, polydipsia
(excessive urination), polyuria (increased urination).
The veterinary surgeon may have
recommended a specialist veterinary diet. Usually, the diagnosis
is based on a blood sample which shows raised liver enzymes. According
to Dr. David Twedt of Colorado State University speaking at the
North American Veterinary Conference, 2003, in most cases, when
liver enzymes are raised there is an (undiagnosed) problem elsewhere
in the body which is having a secondary effect on the liver.
Also known as fatty liver disease,
where fat accumulates in the liver. Obese cats which lose weight
rapidly can be predisposed to hepatic lipidosis. However, it can
also occur in lean cats.
Symptoms usually include: Icterus
(jaundice), anorexia, malaise and occasional vomiting.
Hepatic Lipidosis can occur after
the cat has been fasted/starved this is because after starving
fatty acids accumulate in the liver and as a result the amino
acid intake is inadequate (due to anorexia and perhaps because
• Amino acids (the building
blocks of proteins) are essential in recovery of hepatic lipidosis
and the cat may need to be force fed by syringe feeding. If this
is not possible tube feeding may be advised.
• Vitamin B supplements are
also advised, especially B1 and B12.
• A protein deficiency is not
thought to cause this disease but may encourage the development
of hepatic lipidosis but is not thought to cause the condition.
Protein supplementation may be recommended.
• A deficiency in carnitine
does not seem to cause hepatic lipidosis but studies show that
foods supplemented with L-carnitine can help an obese cat to lose
weigh safely. Carnitine is found naturally in meat, red meat is
the richest source. It is also available in chicken, fish, eggs,
and milk. Vegetables do not contain carnitine. Carnitine can also
be synthesized in the liver from the amino acids methionine and
lysine if sufficient ascorbic acid, niacin, pyridoxine and iron
This is usually a congenital (present
from birth) defect. The blood is shunted from the intestines into
circulation by-passing the portal vein, thus the toxins are not
removed from the blood.
This is usually caused by a bacterial
infection and E. Coli is often present. Treatment is normally
successful when using antibiotics and corticosteroids.
This disease is often caused by liver
flukes and may progress into cirrhosis if not treated. The prognosis
is favourable. Prednisolone is often used for inflammation and
Praziquantel for the liver flukes.
This condition usually occurs secondary
to hepatitis and cirrhosis.
• Sodium and Chloride. Excess
levels of these minerals should be avoided as they may increase
blood pressure. Recommended levels for sodium are 0.20 –
0.35% for cats.
Chronic Hepatitis and cirrhosis
Unvaccinated animals may be at risk
of viral hepatitis.
• Adequate protein is important
(but excessive levels should be avoided) unless the cat has severe
• Antioxidants, Vitamin C and
E are helpful in this condition.
Diet and health
Vitamins. Deficiencies of water soluble
vitamins may occur because of an inadequate intake (due to anorexia)
or through vomiting and urinary losses. Commercial pet foods have
enough water soluble vitamins to support liver disease. However,
vitamin supplements may be needed if the owner is feeding a home
made diet, if the cat has excessive polydipsia and polyuria and
if the cat has been anorexic for a long
Vitamin K. The cat may be deficient
in this essential blood clotting vitamin. Alternatively, there
may be sufficient quantities of Vitamin K but the liver may be
unable to turn it into its active form. Vitamin K supplements
are often given before surgery e.g. for liver biopsies. Vitamin
k is found in liver, fish oils, yoghurt, sea kelp, vegetable oils
and leafy green vegetables.
Fibre. Fibre can be beneficial as
it reduces the availability of nitrogenous waste in the gastrointestinal
tract. Fibre may also bind bile acids, toxins and bacterial products.
Potassium: A deficiency may cause
hypokalemia (abnormally low potassium concentrations in the blood).
Symptoms of hypokalemia include muscle weakness and it can exacerbate
anorexia. Potassium is found in a variety of foods including meat,
poultry, fish and nuts.
Fat: There is no need to restrict
fat levels in cats with liver disease, unless the cat is showing
signs of steatorrhoea (excess fat in the faeces due to malabsorption).
Zinc: In humans with hepatic disease
a zinc deficiency is often present. Zinc is essential for the
action of enzymes and a deficiency may adversely affect ammonia
metabolism. Zinc is found in shellfish, brewer’s yeast,
meat, liver, eggs, fish, nuts and some vegetables.
Taurine: Cats with liver disease
may be deficient in Taurine (perhaps due to inadequate intake
from anorexia). A cat’s liver has a limited capacity to
produce the amino acid, Taurine. It is found in animal tissues
but is not in plant material; therefore vegetarian diets fail
to provide sufficient amounts of this nutrient.
A deficiency causes visual impairment which may cause the cat
to bump into things, failure to reproduce successfully and heart
disease. Taurine is thought to be especially important for cats
with hepatic lipidosis, this is because taurine is an important
component of bile acids (the bile acids absorb fats). Taurine
is found in red meat, fish and eggs.
A diet containing moderate levels
of high quality protein and fat along with complex carbohydrates
is suggested for the management of liver disease.
High quality protein is important
so that it contains all the essential amino acids the cat may
It is important to feed multiple
small meals since the liver has a decreased ability to store food.
It is important the daily feeding
rates are kept to a minimum to help avoid excess nutrients.
1. All family members must agree
to cooperate by ensuring that the correct diet is followed i.e.
no tit-bits, table scraps or other foods.
2. Gradually introduce the new food.
Gradual introduction, by allowing a slow change in intestinal
bacteria, minimises the risk of digestive upset.
3. Quantity of food. It is better
to feed slightly less food, which will be properly absorbed rather
than a large quantity, which could cause an upset.
Success depends on feeding the right amount for each individual.
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