What is the cause of petechiae in horses?

Petechiae in horses, like in humans, are tiny, pinpoint-sized red or purple spots on the skin or mucous membranes caused by bleeding under the skin. This bleeding is due to the rupture of small blood vessels, called capillaries.

Here's a breakdown of the causes:

1. Underlying medical conditions:

* Infectious diseases: Many infectious diseases, like equine influenza, equine herpes virus, strangles, and West Nile virus, can cause petechiae.

* Blood clotting disorders: Conditions like disseminated intravascular coagulation (DIC), a life-threatening condition where the blood clots too easily, can lead to petechiae.

* Immune-mediated diseases: Immune diseases like purpura hemorrhagica, which causes inflammation of blood vessels, can lead to petechiae.

* Endotoxemia: This occurs when bacteria release toxins into the bloodstream, often due to severe infections like colic.

* Kidney disease: Horses with kidney disease can have petechiae due to a lack of clotting factors produced by the kidneys.

* Liver disease: Horses with liver disease can have petechiae due to a decreased ability to produce clotting factors.

2. Trauma:

* Severe physical trauma: Blunt force trauma or even a severe cough can cause petechiae.

* Intravenous injections: Incorrect administration of intravenous injections can cause petechiae at the injection site.

3. Medications:

* Some medications can cause petechiae as a side effect, particularly those that affect blood clotting.

4. Other factors:

* Stress: Severe stress can trigger petechiae in horses.

* Nutritional deficiencies: Lack of vitamin K, which is essential for blood clotting, can cause petechiae.

It's important to note:

* Petechiae are often a symptom of a more serious underlying condition.

* It's crucial to consult a veterinarian immediately if you notice petechiae in your horse.

The veterinarian will conduct a thorough examination, including blood tests, to identify the underlying cause and recommend appropriate treatment.