Ferrets are vulnerable to both ferret specific illnesses and general illnesses. As with many other animals the full list is quite extensive, so I will focus on the more commonplace illnesses. For a comprehensive list you could read one of my favourite ferret books, 'Ferrets' by V. McKimmey or look online at http://www.ferretuniverse.com/health/index.asp for an overview of ferret illnesses and what to do if your pet becomes ill or http://www.pethealthinfo.org.uk/ferrets/qanda.html for some common Q&A's regarding ferret health.
Please be aware that I am not a vet and the facts regarding ferret illnesses that are listed below are gleaned from my own research. Please do not attempt to self-diagnose as you may end up doing your ferret more harm than good and do consult a vet if you notice that your pet has any symptoms or behaviour changes. Remember your ferret doesn't necessarily have to show all of the symptoms that are common to a particular illness for your pet to have it.
Ferret specific illnesses
Adrenal Gland Tumours Are common in ferrets. You may notice hair loss that originates from the around the tail and itchy, dry skin. Females may have enlarged vulva's. Surgery is the most common form of treatment although there are medicines that can be used to make the ferret more comfortable if surgery is not an option.
Epizootic Catarrhal Enteritis Causes inflammation and infection in the intestinal lining. The ferret is likely to have diarrhoea which will in turn cause dehydration. It is also known as the 'green slime' disease due to the dramatic colour change of the bowel movements, which become green or yellow. The pet may refuse to eat or drink but getting them fluids and food is vital and a trip to the vet as soon as possible would be the best course of action.
Insulinoma Is a very common tumour in ferrets. Your ferret may have seizures, back end weakness and stare into space. Commonly you would see your ferret pawing at it's mouth and salivating excessively. Your vet can prescribe medicines to try and treat it or try to operate to remove some of the bulk of the tumour temporarily.
Lymphosarcoma Affects the lymphoid system and is a malignant cancer. Signs can vary according to the part of the body affected but can range from lethargy and weight loss to enlarged lymph nodes and skin tumours. The vet may decide to try and treat by performing surgery or chemotherapy.
Tail blackheads As the name suggets normally affect the tail. These are fairly easy to eliminate and your vet will be able to prescribe some special shampoo.
Other illnesses and parasites to be aware of
Ticks Are parasites that burrow into your pets skin. The bulbous fleshy part that is visible is actually the tick's body part, the head is under the skin. Sometimes you can see their little black leg parts moving. You can try to remove the tick at home using tweezers to grasp the body as close to the head as possible and rotating whilst you gently pull. I would not recommend doing this yourself however as quite often the head part can be left in the skin which then leads to an infection or an abscess. Your vet will be experienced in removing ticks and this is the route I will always take. I have had to remove ticks while working as a dog groomer and it was one of my least favourite jobs!
Ringworm Is a fungal infection that affects the skin. It is an interspecies infection, which means that we can both pass it on to our ferrets or catch it from them. It presents itself with ring shaped red patches which can look similar to eczema. The vet will prescribe an anti fungal treatment.
Fleas Are probably the best known parasite. They suck your ferrets blood and can cause anaemia. You can buy various flea treatments and preventatives from your vet, the most common probably being the pipette type drop treatment. Please ensure that the product you buy is suitable for use on ferrets as using the wrong product or too much of a product can have harmful consequences.
Ear mites Can be difficult to detect as ferrets have dark earwax, but the most common signs of ear mites are persistent scratching of the ears, head shaking and having a head tilt.
Canine Distemper Is a viral disease that is normally fatal as there is no cure. Early symptoms can include an eye squint and an abdominal rash, followed by a rash/thickened skin on the chin. other symptoms that have been associated include skin thickening of the paw pads, conjunctivitis and fever. There is currently no licensed vaccine for ferrets and like all vaccines there can be side effects. You would need to discuss your options with your vet, at the end of the day it is your decision as to whether you vaccinate or not. It is simply a case of weighing up the pros and cons. I had my boys vaccinated yesterday and thankfully they suffered no ill effects, they weren't even lethargic. Each ferret can react differently though and there are so many scare stories on the web that I would just advise you to speak to a trusted exotic or ferret specialist vet.
To round things off I would just like to remind you to please see a vet if you are at all worried about your ferret. Yes it will likely incur a consultation fee but surely this is better than leaving it until the last minute when you will probably will then have more costly bills and a fair amount of heartache.