The liver might not get as much airtime as, say, the horse’s lungs or intestines, but it is an essential organ for life. It accounts for at least 1.6% of an adult horse’s body weight and performs many vital functions: processing nutrients from food; making proteins and bile; storing glucose, vitamins, and minerals; maintaining immune function; and removing toxins from the blood.

At the 2015 American Association of Equine Practitioners Convention, held Dec. 5-9 in Las Vegas, Thomas Divers, DVM, Dipl. ACVIM, ACVECC, Professor of Veterinary Medicine at Cornell University’s College of Veterinary Medicine, described the liver in great detail during the Frank J. Milne State-of-the-Art Lecture.

Liver Function

The equine liver is unique is many ways, one of which is how blood flows through it. Normally, oxygen-rich arterial blood circulates to an organ, and then oxygen-depleted venous blood returns back to the heart and through the lungs to pick up more oxygen to send back through the circulation. But with the liver, the relatively deoxygenated hepatic portal vein provides the organ with a large proportion of oxygen. Ten percent of a horse’s total blood volume of the body resides in the liver, so any disease can have significant consequences.

Divers explained the liver’s multiple functions: “It is a vascular organ, a metabolic organ, and a secretory and excretory organ.” It is responsible for:

  • Bile production and secretion (bile is important for helping metabolize fats);
  • Detoxification processes;
  • Blood storage and filtration;
  • Metabolism of carbohydrates,