Fly strike (a relatively rare condition in the United States) mostly affects rabbits kept in unsanitary conditions and is more likely to occur during summer months. Fly strike happens when flies (particularly the Bot fly) lay their eggs in the damp or soiled fur of a rabbit. Within 12 hours, the eggs hatch into the larvae stage of the fly, known as maggots. It is often a secondary condition to an open wound, extreme feces accumulation on the fur of rabbits due to unsanitary living conditions, prolonged contact with water or other environmental favorable to fly larvae. The maggots, initially small and almost invisible to the naked eye, can burrow into the skin of the rabbit and feed on the animals tissue. Within 3–4 days, the larvae can be large as 15 mm long. In rare cases, if not treated, the rabbit can pass into shock and die. Rabbits most susceptible are rabbits living in unsanitary housing, older rabbits who do not move much, and those who are unable to clean their bottom areas carefully. Rabbits raised on solid floors are more susceptible than rabbits raised on wire floors. Rabbits exhibiting one or more episodes of diarrhea are often inspected, especially during the summer months. In 2002, the medicine Rearguard was approved in the United Kingdom for a 10-week per-application prevention of Fly strike. Fly strike deaths are quick and extremely painful to the rabbit, as hundreds of larvae literally eat it alive.
Myxomatosis and West Nile Virus
Myxomatosis is a threat to the health of pet rabbits. Rabbits caged outdoors in Australia are vulnerable in areas with high numbers of mosquitoes. In Europe, fleas are the carriers of myxomatosis. In some countries, annual vaccinations against myxomatosis are available.
West Nile Virus is another threat to rabbits. There are no vaccinations against this virus and it is fatal. Recourse against the disease includes limiting the number of mosquitoes that are around pet rabbits.
The formation of open sores on the rabbit's hocks, commonly called "sore hocks," is a problem that commonly afflicts mostly heavy-weight rabbits kept in cages with wire flooring or soiled solid flooring. The problem is most prevalent in rex-furred rabbits and heavy-weight rabbits (9+ pounds in weight). The condition results when, over the course of time, the protective bristle-like fur on the rabbit's hocks thins down. Standing urine or other unsanitary cage conditions can exacerbate the problem by irritating the sensitive skin. The exposed skin can result in tender areas or, in severe cases, open sores. The sores can become infected and abscessed if not properly cared for. The problem has a genetic component and animals exhibiting thin foot bristles should not be saved for breeding. Most rabbits can live safely on wire floors with the provision of a resting board or mat. Ultra heavy-weight breeds such as Flemish Giants or Checkered Giants are best raised on solid or partially solid flooring.
The House Rabbit Society recommends that rabbit cages with wire flooring be provided with a resting board in order to prevent this from occurring Alternatively, regular inspection can help head off the development of sore hocks.
An over-diagnosed ailment amongst rabbits is respiratory infection. Pasteurella bacteria, known colloquially as "snuffles," is usually misdiagnosed and has been known to be a factor in the overuse of antibiotics among rabbits.
A runny nose, for instance, can have several causes, among those being high temperature or humidity, extreme stress, environmental pollution (like perfume or incense), or a sinus infection. Options for treating this is removing the pollutant, lowering or raising the temperature accordingly, and medical treatment for sinus infections.
"Runny eyes" can be caused by dental disease or a blockage of the tear duct. Environmental pollution, corneal disease, entropion, distichiasis, or inflammation of the eyes are also causes. This is easy to diagnose as well as treat.
Sneezing can be a sign of environmental pollution (such as too much dust) or food allergy.
While Pasteurella is a bacterium that lives in a rabbit's respiratory tract, it can flourish out of control in some cases. In the rare event that happens, antibiotic treatment is necessary.
Head tilt/wry neck/Encephalitozoon cuniculi (E. cuniculi)
Inner ear infections, certain protozoans, strokes, or other diseases or injuries affecting the brain or inner ear can lead to a condition known as wry neck or "head tilt." Although a heavy infestation of ear mites, an ear infection or injury can result in these symptoms, the most common cause of these symptoms is the protozoan parasite E. cuniculi. This condition can be fatal, due to a disorientation that causes the animal to stop eating and drinking. The drugs of choice for treatment and prevention of E. cuniculi infections are the benzimidazole anthelmintics, particularly fenbendazole. In the UK, Panacur Rabbit (containing fenbendazole) is marketed and recommended as a nine day course to help contain this condition and is a simple oral paste to medicate at home. It is sold over the counter. Users in the US or other countries will need to consult with their veterinarians about use and dosage of fenbendazole.
Dental disease has several causes, namely genetics, inappropriate diet, injury to the jaw, infection, or cancer.
- Malocclusion: Rabbit teeth are open-rooted and continue to grow throughout their lives. In some rabbits, the teeth are not properly aligned, a condition called malocclusion. Because of the misaligned nature of the rabbit's teeth, there is no normal wear to control the length to which the teeth grow. There are three main causes of malocclusion, most commonly genetic predisposition, injury, or bacterial infection. In the case of congenital malocclusion, treatment usually involves veterinary visits in which the teeth are treated with a dental burr (a procedure called crown reduction or, more commonly, teeth clipping) or, in some cases, permanently removed.
- Molar spurs: These are spurs that can dig into the rabbit's tongue and/or cheek causing pain. These can be filed down by an experienced veterinarian with a dental burr.
Signs of dental difficulty include difficulty eating, weight loss and small stools, anorexia, and visibly overgrown teeth. However, there are many other causes of ptyalism, including pain due to other causes. A visit to an experienced rabbit veterinarian is strongly recommended in the case of a wet chin, or excessive grooming of the mouth area.
Gastrointestinal stasis is a serious and potentially fatal condition that occurs in some rabbits in which gut motility is severely reduced and possibly completely stopped. When untreated or improperly treated, GI stasis can be fatal in as little as 24 hours.
GI stasis is the condition of food not moving through the gut as quickly as normal. The gut contents may dehydrate and compact into a hard, immobile mass (impacted gut), blocking the digestive tract of the rabbit. Food in an immobile gut may also ferment, causing significant gas buildup and resultant gas pain for the rabbit.
The first noticeable symptom of GI stasis may be that the rabbit suddenly stops eating. Treatment frequently includes subcutaneous fluid therapy (rehydration through injection of saline solution under the skin), drugs for treatment of the buildup of gas in the digestive tract, massage to promote gas expulsion and comfort, possible drugs to promote gut motility, and careful monitoring of all inputs and outputs. The rabbit's diet may also be changed as part of treatment.
Some rabbits are more prone to GI stasis than others. The causes of GI stasis are not completely understood, but common contributing factors are thought to include:
- a lack of fiber in the diet. Many pet rabbits do not get sufficient fresh grass hay, but are instead mistakenly fed only commercial alfalfa pellets originally developed for rapidly increasing mass in rabbits bred for meat.
- insufficient moisture in the diet. Fresh, leafy greens are a critical part of a rabbit's diet in part because of their moisture content, which helps prevent the gut contents from becoming impacted.
- lack of exercise. Rabbits confined to a cage frequently do not get the opportunity (or motivation) to run, jump, and play, which is critical in maintaining gut motility.
In addition, GI stasis can be caused by the rabbit not eating for other reasons, such as stress, dental problems, or other unrelated health problems.
GI stasis is sometimes misdiagnosed as cat-like "hair balls" by veterinarians not familiar with rabbit physiology. However, unlike cats, rabbits do not have the ability to vomit.