Rabbit Owner's Guide

Common rabbit diseases

Dental diseases

Dental diseases in rabbits are increasingly common today and have been recognised as the underlying cause of numerous other disorders. Rabbits are herbivorous and eat a wide variety of vegetation and roughage. They have teeth that are open-rooted which means that their teeth grow continually throughout their life. Feeding your bunny a proper diet keeps it healthy and the constant chewing will wear down the teeth as they grow.

Signs of dental disease
Early signs of dental disease may be subtle and not immediately noticeable to the owner. Look out for changes in your bunny's food preferences such as when your bunny stops eating certain things that may be difficult to chew. Notice also when your bunny drops food from its mouth while chewing or loses weight. Overgrown incisors may lead to a change in grooming habits and unkempt appearance. Advanced signs of dental disease may be excessive salivation, loss of appetite, malodorous breath, and severe weight loss.

The rabbit may present for another problem such as GI stasis, an abscess, or an infected tear duct, which are all secondary to the primary dental disease.

Common signs:

  • Visibly fractured/crooked incisors
  • Fur wrapped around incisors
  • Presence of pus/discharge around teeth
  • Abscess formation (lumps along lower jay and upper cheek area)
  • Reluctance to eat fibrous foods (for example, hay)
  • Oral pain
  • Loss of weight
  • Bad breath (from oral ulcers)
  • Discharge from nose
  • Lack of grooming/poor coat
  • Excessive tearing/eye discharge
  • Lethargy
  • Excessive salivation (wet chin, wet/saliva stained front paws, slobbering)

Causes of dental disease:

Dietary factors
Your rabbit's diet is very important in maintaining a healthy set of teeth. Rabbits are fussy eaters and would rather eat foods that are high in carbohydrates, simple sugars, fat and those that are extremely low in sugar. High-fibre foods have poorer palatability but are most beneficial to your bunny because indigestible fibre aids digestion and their abrasive nature aids in the maintenance of the continuously growing cheek teeth.

Rabbit mixes and pellets should not be the main component of your bunny's diet because it does not provide the proper roughage your bunny requires for digestion, the proper fibre for wearing their teeth down, and is fattening. This causes their molars to curl as they grow continually. Their lower molars develop points that grow into the tongue and the upper molars develop points that grow into the cheeks. These changes occur gradually over time and can lead to many secondary problems including abrupt loss of appetite and infections.

Acquired dental disease with deterioration of the tooth quality, malocclusion and elongation of the roots with periapical abscesses is another form of dental disease in rabbits. Metabolic bone disease, genetics, and diet are all proposed causes for this problem.

Genetic factors
Due to inbreeding, some rabbits are born with malocclusion. This is when the incisor teeth are overgrown and curled around when they do not meet properly. Rabbits with malocclusion need to have their teeth trimmed every one to two months or have their incisors extracted.

Some rabbits are born with elongated skulls, which also lead to dental occlusion problems.

Metabolic bone disease
This disease is similar to osteoporosis is humans where there is a lack of calcium in bones. The actual disease is more complex and many factors are involved. Most house rabbits with dental disease also contract metabolic bone disease.

Calcium, vitamin D and the parathyroid hormone work together to maintain the bunny's calcium levels. Bones act as storage for calcium and phosphorus; when blood calcium is low, the body retrieves calcium from bones in order to keep blood calcium normal.

Dietary calcium needs to be no less than 0.44% in order for blood calcium to remain normal in rabbits. Anything lower than that will result in calcium deficiency. Most rabbit mixes have do not meet this requirement and therefore should not be the rabbit's primary source of food.

Vitamin D is essential for absorption of calcium in the guy. Exposure to sunlight is crucial for vitamin D synthesis. Animals with low blood calcium can compensate by producing vitamin D with exposure to sunlight and thus, absorb calcium in the guy. This is assisted by the parathyroid hormones.

When your bunny is kept indoors without sunlight and consumes a diet lacking in calcium (such as rabbit mixes), your bunny will be unable to maintain calcium levels, and as a last resort, obtain calcium from bones. This weakens the bones and teeth (both contain calcium) considerably and can cause dental diseases.

Diagnosis
It is imperative that you tend to your bunny's dental disease immediately. Early treatment is required to prevent deterioration and excruciating pain for your bunny. Veterinarians recommend a complete oral examination of your bunny's teeth because dental disease can occur at other parts other than the front teeth. Radiography (x-rays) of the skull under sedation is essential for a full dental assessment. This enables the vet to see all of the tooth roots and the structures surrounding the teeth. It can aid in identification of diseased teeth, which are involved in the formation of abscesses. It is also useful in determining the tooth root involved in eye infections and excessive tearing. Bone infections can also be identified.

Treatment
Trimming overgrown teeth is important and needs to be done every 1 to 2 months. Your bunny should be lightly sedated or anaesthetized so that the pre-molar and molar teeth can be examined at the same time. Spurs (sharp knife like edges) of the check teeth can also be filed. Veterinarians use an electric dental burr to file down teeth. Severely diseased incisors are no longer functional and should be extracted, as rabbits do not need incisors to grind or chew. The presence of diseased incisors act as areas of infection and the sharp edges cause soft tissue damage and oral ulcers. Extractions of these incisors often result in the best quality of life for these rabbits.

If your bunny has an abscess at its cheeks, it will appear as lumps on the lower or upper jaws. This is tricky to treat and needs to be wholly removed. Once the abscess is removed, the tooth should be extracted even if it firmly attached.

The wound should be left open and flushed with antibiotics periodically. Rabbits also require systemic antibiotics and pain relief. It is crucial to keep all dental patients eating well through the course of their disease. These bunnies will be at high risk of developing GI stasis due to the pain experienced from surgery or from dental disease.

Other clinical signs need to be treated appropriately by your veterinarian and it is crucial to address the underlying issue of dental disease promptly as many rabbits may not present with obvious dental disease.

Preventive measures
Given that dental disease is extremely common, it is likely that many rabbit owners will have to go through this with their beloved pets.

Owners can

  • Provide a high fibre diet
  • Provide unlimited hay
  • Avoid giving rabbit mixes, grain or cereal as their main diet
  • Provide sunlight, unrestricted exercise and outdoor access for at least four hours a day
  • Limit rabbit pellets, which are low in calcium
  • Offer a wide variety of fresh leafy vegetables
  • Permit grazing of abrasive weeds and natural grasses where available

Keep in mind that these are tips that you should consult your veterinarian with before acting on.

GI stasis

Gastrointestinal stasis is a serious and potentially fatal condition that occurs in some rabbits. These rabbits usually have severely reduced gut motility. In other words, they do not or have stopped producing faeces. When untreated or improperly treated, GI stasis can be fatal in as little as 24 hours.

GI stasis occurs when food does not move through the gut as quickly as normal. This causes the gut contents to dehydrate and compact into a hard mass. When the gut is impacted, the entire digestive tract is blocked and this causes food inside to ferment, leading to gas build-up. GI stasis can be very painful for your bunny.

Symptoms
If you notice that your bunny has suddenly stopped eating, or that your bunny has stopped passing motion, it may indicate GI stasis. However, some rabbits are more prone to GI stasis than others.

Causes

  1. A lack of fibre in their diet
  2. Insufficient moisture in their diet
    • Many rabbits do not get sufficient grass or hay.
    • Most are fed commercial pellets or rabbit mixes which are fattening and do not contain the required vitamins.
    • Fresh, leafy greens are critical because of their moisture content, which helps prevent the gut contents from becoming impacted.
  3. A lack of exercise
    • Rabbits confined to a cage do not get the opportunity (or motivation) to run, jump, and play, which is critical in maintaining gut motility.
  4. Not eating
    • Can be caused by stress, dental problems and other unrelated health problems.

However, keep in mind that GI stasis is sometimes misdiagnosed as "hairballs" which are actually the effects of GI stasis instead of the cause.

Treatment

  1. Subcutaneous fluid therapy
    • Rehydration through injection of saline under the skin.
  2. Drugs for treatment of gas build-up
    • Simethicone is usually administered to reduce gas build-up.
  3. Massage
    • Massaging your bunny is one of the most effective ways to encourage bowel movement.
    • However, you must exercise caution when massaging your bunny as you may bruise or injure its delicate internal organs.
  4. Change of diet
    • Change your bunny's food to something more palatable.
    • Sometimes force-feeding is necessary.

Preventive measures

Always ensure that your bunny is plied with plenty of dietary fibre from fresh grass and hay. Pellets that are high in fibre are also recommended. Unlimited water is very important to keep your bunny's ingested food hydrated and moving smoothly.

Regular exercise also keeps their skeletal and intestinal muscles strong, well toned and active.

Regular visits to the veterinarian will ensure that your bunny is healthy. Remember to have your vet check your bunny's molars as well.

Scabies

Your bunny can contract scabies, which is a type of mange. It is unlike the scabies mites than attack humans. Scabies in bunnies can be passed to humans and have to be treated with three injections of Ivermectin over a period of six weeks. If untreated, it can lead to hair loss and can be very painful for your bunny.

If you have contracted scabies from your bunny, you can apply lotions that specifically kill scabies mites. Remember to avoid prolonged contact with other humans and animals. You will need to disinfect your bunny's living quarters as well as your clothes and belongings.

Mange is very hard to detect by eye and even deep skin scrapings are not always successful. The presence of mange is accompanied by pruritus (itch); the rabbit will scratch that spot, which can lead to alopecia. The heavy scratching and auto-mutilation of the skin can be accompanied by secondary bacterial infection of the skin. Mange should be taken seriously as it can lead to severe anaemia and death of a rabbit within weeks.

Fur mites

Fur mites are different from scabies mites but have almost the same symptoms. The symptoms such as flaky skin and constant scratching indicate the presence of mite or mange (burrowing mites), but it can also be fungal or bacterial dermatitis. Fur mites are usually found on the back and behind the neck. The skin becomes bald and is usually accompanied by severe scaling.

Bacterial and fungal dermatitis should be considered if no parasites are discovered and should be treated appropriately after culture/determination of the causing agent. This step is important, indeed, some type of medication may be effective against bacteria, but will act as fertilizer for yeast or fungi.

Treatment of skin parasites (mites or mange) is quite simple. For fur mites, usually an injection of Ivermectin is given at intervals of 10 to 14 days. For mange, three injections over a total of six weeks is required.

Those repeats are very important; the adult mites are killed during the first treatment, but eggs that remain in the fur or the environment will hatch and the larvae will grow and lead to a new infection cycle. The second treatment will kill the later ones.

Be it mites or mange, the rabbit's environment should be carefully cleaned with anti-flea products and towels boiled. If the presence of one of those parasites is established, but treatment is not effective, the presence of asymptomatic carriers, which are in contact with the rabbit(s) should be considered.

Abscesses

Many different bacteria can cause abscesses in rabbits and it is usually characterized as a cavity containing pus, surrounded by a capsule of thickened inflamed tissue.

Causes
Rabbits can form abscesses in nearly any organ of the body as well as in skin, tooth roots and bone. The most common causes of rabbit abscesses are bite wounds that become infected and infections in tooth roots and tear ducts. Most facial abscesses are the result of dental disease. Tear duct abscesses can be the result of an elongated upper incisor tooth root blocking the tear duct. The accumulated fluid is a perfect breeding ground for bacteria and an abscess can form easily. Abscesses that form internally can be more difficult to diagnose or manage and include areas such as the uterus, lungs, heart, liver, abdominal fat, intestine and kidneys.

Treatment
There are many ways to treat rabbit abscesses but much of it depends on the location and cause of the infection and the general condition of the rabbit.

Because the pus in rabbit abscesses is so thick, surgical drains are not effective at cleaning the abscess thoroughly, and may lead to a recurrence. Rabbit abscesses often develop finger-like projections or tracts into the surrounding tissue, which are places where new abscesses can form. If these tracts are not removed or cleaned out, the abscess will return.

Even if surgical drains are not used, rabbit abscesses have a higher probability of returning than abscesses in cats, dogs and humans. This can be due to a number of factors such as difficulty in removing all the abscessed tissue due to location, the inability of antibiotics to penetrate the capsule of the abscess, the presence of draining tracts coming off the abscess, and the possibility that the underlying cause of the abscess was not treated.

Most experienced rabbit veterinarians are of the opinion that complete surgical removal of the abscess along with treatment of the underlying cause will give the rabbit the best chance for a complete recovery.

Keep in mind that the abscess wound must be flushed at least twice daily for several weeks to prevent reoccurrence. Also note that while feeding oral antibiotics is a must, it on its own will not adequately cure your rabbit. This is because the abscess wall is so thick that the antibiotics cannot penetrate it. If the entire abscess is completely removed, then the antibiotics might not be necessary or may be used for only a short time. If the abscess was only lanced and drained, then antibiotic therapy might continue for weeks to months.

Other methods include injecting the abscess with antibiotics or other solutions periodically to kill the bacteria inside as well as cleanse the abscess. Oral antibiotics are typically administered as a precaution.

Preventive measures

A rabbit with a healthy diet, frequent exercise and a clean, hygienic environment will be able to avoid developing abscesses. It is recommended that your rabbit should be examined for lumps frequently. If any are found, consult your veterinarian as soon as possible. Quickly determine the cause of the abscess or it will become a recurring problem and may even be fatal. If medication is administered, always follow through and schedule follow-up checks as a precautionary measure to red