A closer look: Bloody Urine (Hematuria/Hemoglobinuria/Myoglobinuria) in Horses
Bloody or brown urine indicates an issue in the urinary tract, including the kidneys, ureters, bladder and urethra. The brown or reddish tint in the urine can be caused by injury to the tissue inside the tract causing bleeding, the breakdown of red blood cells in the body, or the breakdown of muscle tissue. These conditions are called hematuria, hemoglobinuria, and myoglobinuria respectively. Each of these conditions results in blood or red pigments passing into the urine stream, changing the color of the urine.
Bloody or brown urine is uncommon in horses. Horses with bloody or brown urine require immediate veterinary attention. If the horse is a newborn foal, or if the horse has pale gums, emergency veterinary attention is required.
In general, reddish brown urine is considered to be the most severe form of this symptom, as it is typically associated with breakdown of red blood cells. However, accurately determining the color of urine is extremely difficult, and proper assessment requires specialized diagnostic tests. Horses with brown or red urine require immediate veterinary attention to determine the underlying cause.
Testing and diagnosis
Veterinarian care is required for horses with brown or bloody urine. Diagnostic tools include:
- Physical examination
- Blood tests
- Urethral endoscopy
- Rectal palpation
- Biopsy of muscle or urinary tract tissue
Depending on diagnosis, treatments include:
- Blood transfusion
- IV fluid therapy
- Exercise changes
Extreme changes to the color of urine as it leaves the body are cause for concern. Changes to the color of urine once it is outside the body (on the ground, in the snow) are not cause for concern since chemical compounds in the urine may oxidize once they are in contact with the air, turning the urine brown or red.
Vulvar hemorrhage in pregnant mares can resemble hematuria.
Depending on the underlying cause of bloody or brown urine, associated symptoms vary.