Like any aging mammal, ferrets get tumors, cancers and the like. When they reach around age four or later, the odds increase. The average ferret lifespan is between 6-8 years. One of the more common types is a form known as insulinomas. These are tumors from insulin producing cells in the pancreas. In addition to the tumors themselves, they produce excess insulin leading to a type of diabetes.
Some of the external signs that owners should be on the lookout for are large weight loss, lethargy and lack of coordination especially in the hind legs. Healthy ferrets have a high metabolism. They sleep about 18 hours per day, but when they are awake they tend to be extremely active and exploratory.
Naturally, that will decrease somewhat with age, but even older ferrets are still natural ‘seekers’ and frequently hungry. That’s one of the reasons food should be left out for them to eat at will. When they begin to lose a lot of weight, something is wrong. When they become uninterested in their environment, they are usually ill.
Diagnosing insulinomas is usually straightforward. Blood sugar levels are tested from a sample, with the test often repeated after a short fast of a few hours. Insulin levels will often be tested as well. Of course, an external exam for obvious lumps will be performed at the same time the sample is drawn.
Surgery is the most common form of treatment. Visible tumors are removed to reduce the risk of spreading or enlargement. That can also reduce symptoms associated with the tumors. About two weeks later, blood sugar levels will be re-tested, then again every few months to check for re-occurrence.
For those ferrets who aren’t good candidates for surgery, or as an adjunct therapy, there are several drugs that are used to treat insulinomas. Prednisone and diazoxide may be used separately or together. They can help manage symptoms, but don’t eliminate the underlying disease, which will usually progress.
Diet can help control both the likelihood of getting insulinomas and the severity of the symptoms. A high, meat-based protein (about 35% of the total) and high fat content (15%) is standard for ferrets. But sweets, often used as treats for healthy animals, are eliminated. Just as in humans, they can lead to a hypoglycemic episode and disorientation.
Properly treated, most animals recover from insulinomas and live out a natural span.