Surface attraction:
Skin problems in rabbits

Revised February 2002

Luckily, most rabbit skin problems are not particularly serious. But they need prompt attention by a vet, not only to save unnecessary discomfort for bunny, but also because some can be transmitted to humans. Enough to make you feel itchy right away, isn't it!

Moulting

An astonishing number of rabbit owners don't realise that rabbits moult and get a terrible shock when their bunny's fur starts falling out in handfuls! There are a couple of moult related problems rabbit owners should be aware of, apart from the usual grumble of finding rabbit hair in every nook and cranny of the house!

Wild rabbits moult twice a year, but domestic rabbits have more variable moult patterns: some moult continuously, especially those living in centrally heated homes. Many moulting rabbits have a noticeable "tide mark", and if you blow into the fur at the moult line the skin appears dark in colour where the new hairs are growing through. Some of the long or fluffy-coated breeds may even develop transient bald patches during their moult. All this is perfectly normal.

Moulting rabbits require daily grooming to reduce the amount of hair passing through the gut. Constant access to hay is vital to keep the guts moving normally. Be alert to signs of a sluggish digestive system - droppings that are small and dry, or strung together with hair, should ring alarm bells. If you find them, but bunny is behaving normally, you can give a small dose (5 - 10ml) of liquid paraffin. But if your rabbit is subdued in any way he may be developing gastro-intestinal stasis (gut slowing) which needs urgent veterinary attention. For more information on GI stasis, read our article on gut emergencies in pet rabbits.

The moulting process may get "stuck" usually on the flanks, just above the tail, and on the belly. Use a cat moulting comb to remove the dead undercoat.

Ringworm

Ringworm is not a worm at all, but a fungal infection. It gets it's name from the ring shaped lesions seen on the skin of infected humans. In rabbits, ringworm turns up as sores (no rings!) that are usually itchy and found around the head. Ringworm must be differentiated from other causes of scabs and sores, such as ordinary wounds.

Ringworm can be treated in two ways. The first option is antifungal ointment applied directly to the affected area. Secondly, antifungal medicine can be given by mouth. This works by becoming incorporated into the developing hair so that the fungus cannot survive. Treatment may take several weeks.

Ringworm is a zoonosis (a disease that can be transmitted from animal to human) so care should be taken when handling an infected rabbit until the lesion has healed.

Possible sources of infection include hay, soil, or the family cat. Rabbits can also catch ringworm from humans, so remember to protect bunny if any human member of the family comes home with ringworm after handling farm animals!

Ringworm - case history

Baggins, a two year old Dutch rabbit, was brought to the vet with a sore near his mouth. After examining Baggins, the vet thought that ringworm was likely. It turned out that one of the children in the family also had a sore on her face and the kids often cuddled the bunny close to their faces. Ringworm was confirmed following a skin scraping from Baggins; both rabbit and child made a full recovery after treatment from vet and GP respectively!

Cheyletiella mites

Cheyletiella is probably the most common skin problem in rabbits. If you've heard people referring to "mites", chances are this is what they were talking about. Some vets call it "mange mite".

The hallmark of Cheyletiella infection is a patch of dandruff in one particular area of the coat (often on the back, either above the tail or in the nape of the neck), although occasionally it can become much more extensive. It's also called "walking dandruff" because sometimes you can see the dandruff moving due to the activities of the mite! The creatures themselves are too small to be seen with the naked eye.

The mites themselves feed on keratin, which is why infestation tends to develop in areas where dead hair accumulates because they're trickly for bunny to groom thoroughly, namely the nape of the neck and just above the tail. So, if your rabbit has any condition that restricts it's ability to groom itself (dental problem, arthritis, sore hocks, poor balance, obesity), check particularly carefully for mites and seek veterinary advice about tackling the underlying problem.

The sources of Cheyletiella infection are hotly debated. Many vets suspect that many bunnies have low grade infestations that are not detectable at all until either something triggers the mite population to flare up from time to time, or the rabbit can no longer keep the mite population in check by effective grooming. Cheyletiella mites travel on hay, and can carry myxomatosis.

Treating Cheyletiella isn't usually difficult, but may take time. Grooming the areas of dandruff helps by removing the dead hair and dander upon which the mites feed, as does regular application of a cat flea powder. Some vets still treat this condition using medicated baths. This works, but bathing is stressful to bunnies and can be avoided by using other treatments.

Most rabbits vets treat Chyletiella infestation with a course of at least three ivermectin injections given at 7 to 10 day intervals. It's important to finish the course of treatment even if the condition seems to have disappeared. Although ivermectin isn't licensed for use in rabbits, it has been widely used for a number of years without any reported problems.

However, there have been recent developments in treating this condition and some rabbit vets are starting to utilise alternatives to ivermectin. For example, good results are being reported with "Stronghold", a drop-on insecticidal drug used in dogs. Stronghold is from the same chemical family as ivermectin, so it's a logical choice. On the other hand, rabbit deaths have been linked to "Frontline" (it's thought that the carrier chemicals are the problem, not the active ingredient, which is why some vets will use this drug on rabbits with careful dosing and great caution) and some experts feel that the safest option is to stick with the tried and tested ivermectin injections.

Cheyletiella can affect humans. Textbooks of human dermatology describe children developing a rash on their tummy that clears up when the pet is treated but we've yet to hear of a houserabbit owner being affected.

If your bunny develops problems with mites (or ringworm and fleas for that matter) you will need to treat the rabbit's home and bedding. Cheyletiella in particular can survive in the environment (e.g. hutches made from unsealed wood) and re-infect the bunny. Your vet will suggest suitable control strategies.

Fur mites

Fur mites are a separate condition to Cheyletiella and much less well known. They usually affect skin on the back towards the tail, and probably travel in hay and straw. Detailed information is difficult to find.

Fur mites are a bit bigger than Cheyletiella mites and can just be seen with the naked eye as tuny, moving specks. They appear as a contrasting colour to the fur - presumably they have two-tone body colours and you see the pale coloured part of the mite on dark coloured rabbits and vice versa!

Fur mites don't cause any problems in small numbers but they should respond to similar treatment as Cheyletiella.

Ear mites

The ear mite Psoroptes cuniculi is responsible for the condition also known as "canker". Mites invade the ear canal, where they cause intense irritation and result in production of a crusty exudate (discharge) from one or both ears. This condition is quite common in rescue bunnies.

The first signs are subtle: owners may notice their bunny scratching its ears or that the base of the ear is sore to handle. Within two weeks there will be an obvious grey-brown scaly crust within the ear itself. If left untreated, mites and exudate spill out onto the cheeks and neck, which looks as disgusting as it sounds.

Ear mites require treatment by a vet. This will probably consist of ivermectin injections to kill the mites plus topical applications to soften the exudate. Anti inflammatory drugs may be used, partly for pain relief. Do alert the vet and ask for pain relief if you think your bunny is in pain. Antibiotics are sometimes required to control secondary bacterial infection and may be used either topically (directly to the ear) or systemically (injection or by mouth). Occasionally, the crusts are so painful that the poor bunny needs a general anaesthetic to remove them after a few days of treatment to soften up the crusts.

Fleas

Rabbit fleas are uncommon in domestic bunnies, but pet rabbits may be affected by dog and cat fleas. Consequently, flea control programmes in multi animal households should include the rabbit, particularly if any of the animals has an allergy to flea bites.

Fleas transmit myxomatosis: flea control as well as vaccination is needed to prevent this horrible disease. This is particularly important if you have a cat that roams outside. Cats that hunt wild rabbits sometimes come home with rabbit fleas on their face and attached to the edges of their ears.

Advantage, a flea-control drug made by Bayer, has recently (2001) been granted a licence for use in rabbits in the UK. This is a very welcome development, as previously there were no flea treatments licensed for use in rabbits. Advantage is a drop-on treatment.

Sore hocks - Pododermatitis

This topic is covered in a separate article on this website.

Wounds

Any wound on a rabbit carries the risk of developing into an abscess, so it's important that wounds are carefully cleaned.

Minor scrapes and cuts can be treated by bathing with salt water (1 teaspoon to a pint of boiled, cooled water) but more significant wounds will need veterinary attention. Large wounds may require suturing (sometimes under general anaesthetic) and antibiotics to reduce the risk of infection.

Wounds are easier to suture when fresh, but usually require urgent rather than emergency attention. In other words, if bunny cuts itself at midnight it can wait until morning to see the vet. The exceptions are attacks by other animals, or bleeding that won't stop despite firm direct pressure for at least 20 minutes.

Lumps and bumps

There are lots of causes of lumps including abscesses, cysts, tumours, and old scars. Vaccination reactions sometimes leave small lumps beneath the skin of the scruff. If you find a new lump on your bunny, especially if bony, check there's not a symmetrical lump on the other side or on another rabbit before rushing off to the vet!

Sometimes the identity of a lump can be guessed at by what they feel like: for example, fluid filled lumps are usually cysts. But lumps can be better differentiated by inserting a large gauge needle into the lump ("aspiration cytology") to obtain a sample of the contents.

Abscesses in rabbits tend to develop a thick fibrous wall and the whole thing, wall and all, may need to be surgically removed. This can be serious or impossible undertaking if the abscess extends into vital areas such as the inner neck or skull.

Full identification and treatment of other lumps may also require surgery, but this depends upon factors such as age of the rabbit; its general health; and whether the lump is causing any problem.

Vent Disease - rabbit syphilis

"Vent" is rare in housebunnies - it's a sexually transmitted bacterial infection usually seen in breeding animals. Rabbit syphilis is not zoonotic!

Sores develop around the vent (genital) area and sometimes on the face. Treatment is with antibiotics: there's some debate whether topically applied cream is adequate or whether injectable antibiotics are required, but most authorities recommend injectable penicillin as treatment, which is remarkably well tolerated and does not seem to cause any gut problems.

Rabbit pox

Rabbit pox is a viral disease that closely mimics rabbit syphilis. It causes crusty, scabby lesions around the genital region, lips, and eyelids that eventually clear up by themselves after a few weeks or months.

Pox tends to be diagnosed when "vent disease" fails to respond to antibiotics, but it can be confirmed using skin biopsies and blood tests. This is recent and unpublished information, which has not yet reached textbooks of rabbit medicine.

Other viruses

Myxomatosis is a virus that affects the skin as part of it's attack. If a vaccinated rabbit does catch myxomatosis the disease is usually mild and confined to the skin. It may be as insignificant as a single lump on the face, although sometimes the disease can be quite severe even in vaccinated rabbits. Rabbits in this situation at least stand a chance of survival if carefully nursed, whereas unvaccinated rabbits usually die if they develop myoxmatosis.

Warts can be caused by the Shope fibroma virus. You may have heard of it because myxomatosis vaccine is made from a special strain of this virus.

Self mutilation

Rabbits who are stressed, bored or in pain may chew themselves. These rabbits need a thorough veterinary assessment to rule out skin disease before blaming a behavioural problem. Identifying and correcting the underlying cause usually helps. Self-mutilating behaviour may be hereditary in some rabbits: there are reports of successful treatment of a self-mutilating strain of labortatory rabbits using low doses of haloperidol, a tranquillising drug used to treat schizophrenia-like illnesses in humans.

Diagnosing skin problems

Accurate diagnosis of skin problems may require special tests, which can work out quite expensive. Insurance, as always, is a very good idea! :

• Skin scrapings or skin vacuum samples can be examined under the microscope.

• Aspiration cytology can identify the type of cells inside a lump, for example pus cells or cancerous cells

• Bacterial and fungal cultures identify infections and guide antibiotic or anti fungal therapy

• Skin biopsy involves taking a small but full thickness sample of skin to examine under the microscope

• Wood's Lamp examination is to look for ringworm - some species fluoresce when exposed to ultraviolet light!

This article originally appeared in Rabbiting On (journal of the British Houserabbit Association) in Spring 2000. It was written by Dr Linda Dykes and Owen Davies BVSc MRCVS. This version was revised by Linda Dykes in February 2002.

This information is brought to you by the Rabbit Welfare Fund - the charitable wing of the Rabbit Welfare Association. If you love rabbits, please consider supporting the Rabbit Welfare Fund. You can make a donation, or you may like to join the RWA. The 17.50 adult subscription includes a subscription to "Rabbiting On", a fabulous quarterly magazine packed with health, behaviour and care advice to help you build a wonderful relationship with your bunny - whether s/he lives indoors or out.

Copyright BHRA/RWA 2000/2002