Your older horse is down. He’s irritated and in pain. You think it’s colic. You take him for a walk, administer medication. Nothing works. He’s still in pain and your worry is growing. Now what? Call the vet. It’s likely strangulation colic, and it must be treated now.
What’s a lipoma?
A lipoma is a benign, fatty tumor that grows inside the body. The lumps themselves aren’t cancerous, and are generally harmless and painless.
In humans, the cause of lipomas is unknown; however, they often appear after an injury, and there’s thought that there might be a genetic component. They show up in humans and horses of all size and body condition, from thin to overweight so while it is fatty tissue, diet and overall fitness don’t seem to be factors in management or prevention. The only known risk factor is age. Since they take time to develop and continue to grow over time, they’re typically only found in older horses.
How do they cause colic?
While non-cancerous, lipomas can cause pain and complications because of where they tend to grow in a horse’s abdominal cavity. Around the horse’s intestines is a thin sheet of tissue called the mesentery. The mesentery is where the lipoma starts. Over time, it grows larger and develops cord-like stalks that hang down. When it does this, the lipoma is said to become “pedunculated” and pose risks to your horse. Since the stalks hang down, they also can get looped around the intestines. If the loop tightens, it cuts off circulation and the digestive flow in the intestines, which causes the strangulation.
How are lipomas diagnosed?
Unless you suspect something, lipomas often go undiagnosed. There are ways that you can diagnose a lipoma once it’s become problematic to avoid strangulation colic.
A vet can complete a rectal exam of the small intestines, as they’ll be able to feel most lipomas and uncover most obstructing lipomas. An abdominocentesis, a procedure where fluid is taken from the horse’s abdomen for testing, can also be useful. Many vets will discover an increase in protein and white blood cell count in the abdominal fluid of horses with strangulation lipomas.
Are lipomas treatable?
The most effective treatment is surgical removal. It’s best to do this when the lump is still small to reduce the likelihood that it continues to grow and cause other problems. Surgically removing lipomas when they’re small and before they’ve wrapped around the intestines is also less invasive.
Is your horse at risk?
Lipomas can show up in horses of any size and body condition. Early indicators of a lipoma are similar to colic. Keep an eye on your horse if he starts to show signs of discomfort, such as restlessness, frequent rolling, pawing, biting or staring at his flanks, stretching out, sweating, or generally exhibiting low energy—or a combination of these symptoms. This is especially true if your horse is older, and the symptoms are persistent and out of character.
If your older horse does colic, monitor symptoms and progress. If symptoms don’t improve with typically effective measures, such as medication or walking, contact a vet immediately. Strangulation lipomas will require surgery. Colic from strangulation lipomas is treatable, often with a full recovery, if surgery is done quickly.