Hepatic Lipidosis

by Olivia Inoue, DVM, MS, DACVS

Hepatic Lipidosis or fatty liver syndrome is most commonly seen in pony breeds and occasionally in full size horses. The process in which these animals get hepatic lipidosis is never straight forward and can be confusing. In general a horse goes off feed due to a fever, colic, delivery of a foal, or other ailment and the body needs energy in the form of glucose. The body mobilizes fat into the blood stream and then to the liver to be converted into glucose - energy. The problem is the liver gets swamped with fat and it crowds out the liver cells and then the liver does not work properly.

The liver is responsible for detoxifying the blood stream, making certain proteins, converting fat and proteins in to glucose and other vital functions. When the liver cells can not work, toxins build up and these make the horse feel poor and not want to eat. The body still needs energy and it mobilizes more fat from the body and it goes to the liver crowding the liver cells even more. The starvation, energy requirements, moving fat deposits and crowding the liver becomes a viscous cycle that needs to be stopped.

Horses with hepatic lipidosis are often depressed, weak, and have recent and sudden weight loss. Some horses may have a low grade fever and elevated heart rate. Blood work reveals increased liver enzymes, low blood glucose, mild to moderate dehydration and there may be evidence of fat in the blood.

The main goal of therapy is stop the viscous cycle of fat entering the liver and to get to the horse to eat. Anything the horse will eat is key, including grass, grains and hay. Intravenous fluids including glucose are important to reverse the dehydration and give energy. Many horses will be started on oral antibiotics and ant-ulcer medications. Some horses on IV fluids and green grass will respond and start to eat normally. Others need to be force feed a high calorie gruel either by large syringes every 2-3 hours or even feed by stomach tube 3-4 x per day. Calories in the form of carbohydrates are key to reversing this disease.

It is a frustrating disease to manage and often requires many days of intensive care and treatment. Some horses sadly do not survive because of the severity of the liver damage, but if caught early and treated aggressively horses can be treated successfully. Ponies which are excessively overweight, pregnant and have just delivered a foal are more to prone this problem. Diet management is key in trying to prevent this problem, but in some cases it is not preventable in all cases. The Equine Center offers feed management suggestions to help minimize the occurrence of this troubling disease.