Anemia in Horses

Anna O'Brien, DVM
Vet Reviewed
By Anna O'Brien, DVM on Mar. 2, 2012
Anemia in Horses


Anemia in horses is defined as low blood volume. There are a variety of different causes of anemia, and it usually occurs secondary to some other health issue the horse may be experiencing.

Symptoms and Types

  • Unusually poor performance
  • Weakness
  • Lethargy
  • Loss of appetite
  • Depression
  • Hair loses luster
  • Heart murmur
  • Pale mucous membranes


Anemia can be classified as acute (rapid onset) or chronic (persistent or long-lasting).  Acute anemia is caused by rapid blood loss, such as with a traumatic injury or ruptured blood vessel.  Chronic anemia is sometimes a bit more complicated and can have many causes, some of which include cancer (especially types that affect the bone marrow), chronic kidney disease, gastric ulcers, or severe nutritional deficiencies.


The diagnosis of anemia is very straightforward, but finding the cause of the anemia is often not as simple. A simple blood test that measures packed cell volume (PCV) will tell the veterinarian if the horse is anemic and if so, how badly affected. The PCV does not tell the veterinarian why or how the horse became anemic.  Sometimes, further diagnostics are required to find the cause, particularly if the anemia is severe and the horse is greatly debilitated.



Treatment will ultimately depend on the underlying cause of the anemia. In the case of acute hemorrhage, the source of the blood loss must be stopped. This may require surgical intervention and is usually an emergency situation.  After the source of blood loss is identified and hopefully corrected, the horse will likely be placed on IV fluids. These fluids will help bolster the circulatory system until the bone marrow is able to produce more red blood cells. For chronic anemia, management of the cause, if possible, is the best way to help the horse.

Living and Management

In all cases of acute anemia, strict rest is required. The length of the rest period will be dictated by how much blood the horse has lost. For chronic anemia, the veterinarian may prescribe a dietary supplement of iron and other vitamins such as B12. 


After any invasive surgical procedure, the horse should be allowed plenty of rest and time for recuperation and adequate healing. Older horses or horses recovering from chronic diseases should be provided ample good quality forage, along with nutrient supplements, as the veterinarian dictates. 


Anna O'Brien, DVM
Vet Reviewed


Anna O'Brien, DVM


Anna O’Brien, DVM is a large animal veterinarian. A 2008 graduate of Purdue University, she currently works in Maryland, just outside of...

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