Fleas are small, usually dark-colored, wingless insects that affect many different animals, including ferrets. Once it attaches itself to the ferret's skin, it will bite the animal and feed of its blood, causing skin irritations and even anemia. While most ferrets are not overly sensitive to fleas, some may develop allergies. Fleas also reproduce quite quickly, laying batches of eggs on the host, which can then spread to the ferret's habitat or anything it touches. To prevent a flea outbreak in your home or a flea infestation in your ferret, bring the animal to your veterinarian at the first sign of fleas.
Common symptoms associated with fleas include biting, chewing, scratching or licking the infected area. The ferret will do this in an attempt to dislodge the pesky critters from its body. Another good indicator of fleas is “flea dirt,” or dried blood left behind on the ferret's skin by feeding fleas. Some ferrets develop skin lesions (or papules) that resemble acne, while others develop scabs or hair loss.
Anemia is also a problem for a ferret with fleas, especially when there are a lot of fleas on the animal, constantly draining it of blood. Moreover, a ferret may develop a secondary infection if it frequently bites, chews or scratches at an area and breaks the skin. This can lead to a variety of conditions, including, in severe cases, tachycardia -- an abnormally rapid heart rhythm.
There are many different flea species, however, those affecting ferrets will depend on the source of the fleas. For instance, ferrets which spend time outdoors may contract the parasite from wild animals, while domestic ferrets will usually contract them from cats (the Ctenocephalides felis species) or from dogs (the Ctenocephalides canis species). There is also a flea species in the southwestern United States which can spread a form of the bubonic plague.
Before diagnosing flea infestation, a veterinarian will first rule out other causes for anemia, biting, skin irritations or hair loss. These may include adrenal disease or infestation with mites or other parasitic organisms. But a veterinarian will typically spot fleas or “flea dirt” through a physical examination.