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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.

Anaemia is an abnormally low number of red blood cells circulating in the bloodstream. 

Anaemia is a condition in which the number of red cells circulating in the blood is below the normal range for an animals species, breed and age. Some breeds of dog eg Greyhounds, Whippets, Borzois and Lurchers have higher red cell counts than other breeds. Young puppies and kittens have lower red cell counts than adults.

There are two main types of blood cell :

  • Red cells (also called erythrocytes)
  • White cells

The red cells are produced by specialist cells in the bone marrow. One of the main roles for red blood cells is to carry oxygen around the body. The oxygen that is breathed into the lungs gets bound to haemoglobin in the red cells, and in the body's tissues the oxygen is released.  If there are not enough red cells in circulation the tissues get starved of oxygen (called hypoxia) - with serious consequences, because oxygen is essential for normal cell function.

There are 3 main causes of anaemia :

  1. The animal loses red cells due to bleeding at a rate that exceeds it's ability to produce more red cells from the bone marrow. Sometimes bleeding is obvious but on other occasions it may not be. Bleeding externally is obvious, bleeding into urine is usually noticed as a pink or red discolouration, and bleeding into the large intestine (eg colon) may be seen as fresh red blood in a stool, but bleeding high up in the gut (in the small intestine) gets changed producing a black sticky stool called melaena. Vomited blood often looks brown in colour - like coffee grounds.
  2. The bone marrow is unable to produce adequate numbers of red cells to maintain adequate circulating numbers. If the disorder of the bone marrow also affects white cell production there can be low white cell numbers in the circulation (called leukaemia) as well.
  3. Sufficient red cells are being produced but they are being destroyed in the bloodstream and have a shorter lifespan. This occurs, for example,  when the body produces antibodies against it's own red cells causing them to disintegrate (called haemolysis) - this disorder is called autoimmune haemolytic anaemia. Haemolysis can also be caused by infectious agents including Feline Infectious Anaemia - caused by Haemobartonella felis (common in cats) and Haemobartonella canis (uncommon in dogs).

Signs of anaemia that owners may notice include :

  • Pale gums and other visible mucous membranes
  • Poor ability to exercise - sometimes collapse if anaemia is severe
  • Weakness
  • Increased heart rate and increased breathing rate

Treatment of anaemia involves managing the underlying cause and, in some cases, blood transfusion. In some countries there are established blood transfusion services for animals just as there are for humans.

There are many causes of anaemia and identifying the specific cause in a patient is a skilled procedure which requires the analysis of a series of laboratory tests by a veterinarian. CLICK HERE for more Information

Last updated : September 2013