First broadcast on as part of it's Focus On Nutrition Week 

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.

Cod liver oil is a very popular as nutritional supplements in humans and in pets - but what do they contain and are they good or bad for cats and dogs ?

In typical analysis (the following are based upon 3 UK samples mixed) cod liver oil is composed of the following :

Nutrient Amount Nutrient Amount
Water Trace Retinol (Vitamin A) 18,000mg/100g
Protein Trace Vitamin D 210mg/100g
Fat 99.9% Vitamin E 20mg/100g
Carbohydrate Nil bCarotene (Vitamin A) Trace
All Minerals Trace All other vitamins Nil
Energy content (kcal) 899kcal/100g Energy content (kJ) 3696 kJ /100g

From this Table  it can be seen that cod liver is :

  • High in energy (calorie) content
  • High in Vitamin A content
  • Contains some Vitamin D and E

To put things into perspective the energy density of glucose liquid  is 549 /kcal/100g  (1355 kJ per 100g) and Jam is up to 261 kcal/100g (1116 kJ/100g). 

Carrots contain up to an average of 8,115 mg carotene/100g  (maximum 11,000mg) and no retinol or vitamin D. They contain 0.56 mg Vitamin E/100g.

Polyunsaturated margarine contains 775mg retinol/100g,  7.94mg Vitamin D /100g and variable amounts of Vitamin E.

If animals need nutritional supplementation of energy or Vitamin A cod liver oil (and other fish oils) are a good idea, However, if your pet is eating a balanced complete ration you could provide too much Vitamin A. Many pet foods are already supplemented with vitamins and can already contain large amounts of Vitamin A.

Cats are frequently presented to veterinarians showing the toxic effects of excess vitamin A which causes new bone to be deposited around joints causing pain, lameness and spinal problems. This is often associated with eating liver (also high in vitamin A content) or cod liver oil supplementation.

Provet advice : Don't give cod liver oil supplementation unless you are sure you won't exceed the toxic dose for Vitamin A in your pet. Ask your veterinarian for his/her advice.


Updated October 2013