Caused by eating something indigestible, such as an eraser, a rubber band, some fabrics, or even a good-sized hairball (accumulated from grooming), which gets stuck. Symptoms may include (one or more of) lack of bowel movement, constipation, bloating, vomiting or heaving, drooling, and others. Blockages may occur at any point in the digestive tract, from the throat through the lower intestine, even in the stomach where the object may move around and produce only intermittent symptoms. Blockages are serious and occasionally fatal; the most important immediate concern is to keep your ferret hydrated, which you can do by giving him 5 cc of water every 4 hours from a baby feeding syringe. You can try giving your ferret large doses of hairball remedy every 30 minutes for an hour or two to see if the blockage passes, but if not, take him to a vet right away for an X-ray, barium study, and/or surgery to remove it.
Tumors or Lesions of the Adrenal Glands
Symptoms vary, including hair loss spreading from the base of the tail forward, lethargy, loss of appetite, and loss of coordination in the hindquarters. In females, often the most prominent sign is an enlarged vulva as in heat. Often, however, a tumor will be present without showing any signs at all, so if your ferret is going in for any surgery, the vet should take a look at the adrenal glands as well (if time permits – ferrets lose body heat very quickly in surgery). The left gland seems to be affected more often than the right.
Islet Cell Tumors (insulinoma)
These are tumors of insulin-secreting cells in the pancreas. Their main effect is a drop in the blood sugar level, and they are also common enough in older ferrets, even without symptoms, that if your pet is having surgery for something else, a quick check is worthwhile. Symptoms include lethargy, loss of appetite, wobbly gait, and pawing at the mouth; in more severe cases attention lapses (staring into space) or seizures may also occur. If you’re more than a minute from your vet and your ferret has a low enough blood sugar level to be having seizures, call the vet and ask if you should rub Karo (corn sugar) syrup or honey on your pet’s gums to raise it just enough to bring him out of the seizure.
Lymphoma or lymphosarcoma
This is a cancer of the lymphatic system. There are two main types, "classic" and juvenile. Classic lymphoma occurs in older ferrets and causes enlarged lymph nodes and irregularities in the blood cell count, but often the ferret doesn’t show any outward signs until the disease has progressed pretty far, at which point the ferret suddenly gets very sick. Conclusive diagnosis is by aspiration or biopsy of a lymph node, and treatment is chemotherapy. Juvenile lymphoma is completely different. It affects ferrets under 14 months, doesn’t generally cause enlarged lymph nodes, and hits very hard and fast.
Splenomegaly [Enlarged Spleen]
In situations where a neoplasm is not present [this is a common symptom of lymphosarcoma], the pros and cons of splenectomy should be discussed with your veterinarian. If an animal simply has a large spleen, but shows no signs of illness or discomfort, it is safer for the animal to leave it in. However, if the animal shows signs of discomfort, such as lethargy and a poor appetite, or a decrease in activity, the spleen should probably be removed. These animals also need good nursing care to get them back on their food. Often caused by H. mustelae infection (see below). With proper care – recovery rates are over 90%.
Helicobacter mustelae Infection
A bacterial infection of the stomach lining, Helicobacter mustelae is extremely common in ferrets. Animals with long-standing infections (generally older animals), may develop gastric problems due to the bacteria’s ability to decrease acid production in the stomach. Signs of a problem include repetitive vomiting, lack of appetite, and signs of gastric ulcers (see above). Helicobacter infection and gastric ulcers often go hand in hand – the relationship between infection and gastric ulcer formation has not been totally worked out, although there is currently a lot of research in this area.
Cutaneous Vaccine Reactions
Subcutaneous vaccination with rabies or other vaccines may, over a period of weeks, cause a hard lump at the site of vaccination. The lump simply consists of a large area of inflammation and most commonly are seen around the neck. The lumps can be removed, and generally do not cause a major problem for your pet. Similar lesions may be seen in vaccinated dogs and cats.
Urinary Tract Infections (UTIs) and Prostate Trouble
Signs include frequent urination, straining to urinate, and possibly funny-looking or smelly urine. Un-spayed females in heat, and spayed females with swollen vulvas due to adrenal disease, are particularly prone to UTIs. Treatment generally consists of a course of antibiotic (usually Amoxicillin); if the ferret doesn’t respond to that, the possibility of bladder stones should be considered. In males, what looks like a UTI may be (or be aggravated by) an inflamed prostate, also generally caused by adrenal disease. In this case the prostate, which is normally tiny, can be palpated, and a greenish goo can often be expressed from it. Taking care of the adrenal problem should clear up the prostate trouble too.