Calciferol Poisoning in Horses

Calciferol is the active ingredient in many types and brands of rat poison. A high dose of calciferol will cause a destabilization of calcium in the body, leading to a condition of hypercalcemia, and eventually causing calcification of the tissues and organs of the body in the rat.

On occasion, horses will come into contact with horse feed that has been contaminated with calciferol, perhaps when the poison has been laid down in storage areas, and as a result are inadvertently poisoned. This often occurs without the knowledge of the caretaker.

Symptoms and Types

• Loss of appetite (anorexia)
• Loss of weight
• Loss of body condition
• Difficulty breathing (dyspnea)
• Excessive thirst (polydipsia) with increased consumption of water
• Increased production of urine (polyuria)

Causes

• Ingestion of calciferol, usually inadvertently
• Usually involves the contamination of hard food with rat poison

Diagnosis

Your veterinarian can diagnose calciferol and/or rat poison poisoning toxicity since the symptoms of rat poisoning are pretty telltale. You will need to provide a thorough history of your horse's health leading up to the onset of symptoms, and your veterinarian will gather fluid samples for laboratory analysis. Through blood and urine analyses your veterinarian will be able to identify the presence of calciferol, as well as other toxins, in the system. This is a very important step to ensure that the right approach is taken for immediate and effective treatment.