Ferrets have several well-known but unique health problems. Understanding these problems and educating yourself about symptoms of disease will allow you to better care for your pet and minimize future health care problems.
Hypoglycemia (Low Blood Sugar)
Ferrets over three years of age that are showing signs of lethargy (lack of energy) or trouble walking may be exhibiting signs of low blood glucose levels (hypoglycemia). This condition is brought on by excess insulin excretion by a cancerous growth of the pancreas, commonly known as an insulinoma. This condition will require blood tests to diagnose the specific cause of the lethargy. If glucose levels are low, medical and/or surgical therapy will be necessary to help the ferret maintain adequate blood glucose levels. This disease is not curable, but with proper treatment, many ferrets can live a fairly normal life for up to two and a half years post-diagnosis.
Like dogs and cats, ferrets are susceptible to heartworm disease. Heartworms are transmitted by mosquitos. In ferrets, the symptoms are generally severe. Affected ferrets are often weak, have a hard time breathing, and may have a distended abdomen. Radiographs (x-rays) may show fluid in the chest cavity and, if an ultrasound is available, live heartworms may be noted in the right side of the heart. Both the disease and treatment may be life-threatening.
"In ferrets, the symptoms of heartworm disease are generally severe."
Neoplasia or Cancer
Ferrets can be affected by a variety of cancerous conditions. Skin growths are a common finding on adult ferrets and are usually found to be either basal cell carcinoma or mast cell tumor, but hemangiomas and squamous cell carcinoma have also been diagnosed. The most common cancerous condition amongst ferrets is lymphoma or lymphosarcoma. This condition is a cancer of the lymphoid system and can affect the lymph nodes, the liver, and/or the spleen.
Enlarged Spleen (Splenomegaly)
During a physical examination, your veterinarian may palpate (feel) for an enlarged spleen, especially if your ferret is an older pet. While not a sign of any one specific disease, this finding does require further investigation.
"An enlarged spleen is a serious finding that indicates the need...to determine the cause."
Enlargement of the spleen may be caused by inflammation, viral or bacterial infections, cancer, and/or heart disease. An enlarged spleen is a serious finding that indicates a need for laboratory testing to determine the cause. Occasionally, diagnostic tests are negative for any specific disease, in which case the diagnosis of "benign hypersplenism" or "benign idiopathic splenomegaly" will be made.
Aplastic anemia is a condition in which red blood cell production in the bone marrow has been suppressed, resulting in a shutdown in production of new red blood cells. Bone marrow suppression may also suppress the production of white blood cells and platelets. This condition occurs in female ferrets that are not spayed and not bred when they are "in heat." Sexually mature female ferrets that are not bred will stay in heat indefinitely, causing persistent high estrogen levels. High doses of estrogen suppress bone marrow function. This condition is rarely seen in today’s pet ferret, as most female ferrets are spayed before sale.
"All female ferrets that will not be bred at every heat cycle should be spayed by four to six months of age."
Signs of aplastic anemia include lethargy and pale mucous membranes, which can be readily observed by looking at the gums. When the intact female ferret is examined, her vulva will usually be found to be swollen and enlarged, indicating persistent estrus or heat. Initial treatment to stabilize the ferret includes hormonal therapy to bring the ferret out of heat, antibiotics, iron supplementation, and vitamin B injection. A ferret with severe anemia may need a blood transfusion or may die. Once stabilized, the ferret should be spayed. This is a serious and expensive disease to treat. All female ferrets that will not be bred at every heat cycle should be spayed by four to six months of age.
Ferrets, like dogs and cats, do not sweat in the way that humans do. Therefore, ferrets are very susceptible to extreme heat. They should be maintained at an environmental temperature below 90°F(32°C).
“Heat stroke is a true, life-threatening emergency.”
Heat stroke is manifested by open mouth breathing and an elevated rectal temperature (normal temperature is between 100-104°F or 38-40°C). Heat stroke is a true, life-threatening emergency. First aid involves rapidly cooling the ferret; this can be done by wrapping the feet with towels soaked in cold water or fans. Be careful not to chill the ferret too much. If the ferret begins to shiver, stop the cooling process. Do not delay taking your ferret to the veterinarian if you suspect that it may be suffering from heat stroke. During the trip to the veterinarian, wrap the ferret’s feet in cool, wet towels, or transport it in an air-conditioned vehicle. Your veterinarian will stabilize the ferret and slowly reduce its temperature using various medically safe procedures. Hospitalization is required after the temperature has been normalized, to monitor vital signs and ensure that the ferret is stable.
Ferrets can become infected with canine distemper virus. This disease is usually fatal to ferrets. Clinical signs include loss of appetite, thick discharge from the eyes and nose, fever, thickened and hard skin on the footpads, and/or a rash on the chin, abdomen, or groin. Treatment is supportive, including fluids, antibiotics (for secondary bacterial infections), nutrition, and oxygen therapy. Since the symptoms of distemper and influenza are similar, treatment should always be attempted. With distemper, the ferret will usually succumb to the disease within one to two weeks; with influenza the ferret should be better within one to two weeks.
To prevent this fatal disease, all ferrets that are at risk of exposure should be vaccinated. Discuss the risks of this disease with your veterinarian.
Ferrets can both contract and spread human influenza, or flu. Symptoms are similar to those of people with the flu (or to ferrets with distemper). Treatment consists of antibiotics (to prevent secondary bacterial infections), decongestants, and anti-viral therapy.
"Ferrets can both contract and spread human influenza, or flu."
Occasionally, hospitalization for supportive care such as fluid therapy or force-feeding by your veterinarian will be required. Never give your ferret any over-the-counter medications or prescription drugs without checking with your veterinarian first. Like dogs and cats, ferrets can be easily poisoned or killed with common human medications.