When owning a pet rabbit, it is important to know about the animal's most common health issues. One of the most prevalent is ileus, a complex condition involving poor gut motility that, if left untreated, can be fatal.

"The gut function slows or stops whenever a rabbit feels pain or stress from another illness," says Isobel Jenkins, veterinarian for the Society for the Prevention of Cruelty to Animals, Hong Kong www.spca.org.hk She says ileus is probably the most common condition she sees in rabbits because it can be so easily triggered - even the stress of being taken to a vet's clinic can spark it.

Symptoms include a decreased or lack of appetite, decreased or no faecal production (faeces can also appear smaller and dry), tooth grinding due to pain, and a hunched posture. Jenkins says prevention includes high-quality husbandry and health care, including an optimal diet of hay, pellets and fresh vegetables.

Dental disease is another typical issue, accounting for about half the sick rabbits taken to the SPCA.

"Rabbit teeth are constantly growing and are designed to chew high-fibre grass, which wears them down," says Jenkins. "However, captive rabbits are often fed low-fibre pellets, snacks and treats, thus they spend less time chewing, which means the teeth do not get worn down as fast, yet continue to grow at the normal rate."

Owners should look for lack of wear, which leads to sharp spikes on the teeth. The roots of the teeth will become bent, so changes occur in the skull. "In severe cases, infection can cause life-threatening abscesses," the vet says. Other symptoms include reduced appetite, excessive salivation, swelling on the side of the face and tooth grinding.

Prevention calls for feeding the rabbit as naturally as possible, Jenkins says, "preferably with fresh grass, but in Hong Kong this is not realistic for many, so the second-best option would be timothy or orchard grass hay". Because dry food pellets should be given according to the rabbit's weight and body condition, it's best to get a vet's advice on proportions, she adds.

Another issue is pasteurellosis, a bacterial infection that can be contracted from the mother after birth, by contact with other rabbits, or through infected surfaces or objects. There are three ways that the infection can progress: the rabbit resists the infection; the rabbit develops the disease, but its immune system eventually clears the infection; or the rabbit becomes a lifelong carrier with or without symptoms.

"Symptoms can be mild or severe, usually affecting the respiratory tract," the vet says. "The rabbit develops a white, creamy nasal and ocular discharge. The bacteria can also cause conjunctivitis, middle-ear infections and abscesses in the lungs and other tissues."

The best forms of prevention are good hygiene, not mixing rabbits that do not normally live together, and not boarding your pet at facilities where other rabbits are kept. "There are currently no vaccinations, and it is estimated that between 40 and 72 per cent of apparently healthy rabbits may carry this bacteria," the vet says.

Rabbits can also be prone to crystals, or urine sand. "Normal urine colour can vary from clear yellow to cloudy dark brown. Calcium ingested in the diet is excreted through the kidney and if present in high concentrations can precipitate into crystals which grow into sand or stones," Jenkins says. "It is more common in Hong Kong because of diet and is further confounded by Hong Kong's hot, humid weather, a climate rabbits are not adapted for, so mild dehydration can occur which further concentrates urine."

The vet says symptoms include sudden changes in the urine, increased urination or a change from the normal colour with or without increased water consumption. "As the cause is dietary, timothy and orchard grass hay, which are lower in calcium, should be provided. Avoid alfalfa hay, because it has higher calcium content, and also check it is not present in the rabbit pellets." In addition, she says feeding rabbits a variety of fresh vegetables daily is a good way to increase the water content of their diet.

Finally, owners must note that rabbits are highly susceptible to broken bones. "Rabbits have delicate bones compared with other mammals of similar size, and this makes broken bones more likely even after minor falls," Jenkins says.

Because rabbits have well-developed muscles that can allow them to walk despite a fracture, any lameness, reluctance to walk or change of gait should be checked by a veterinary surgeon, especially if it starts suddenly.

Jenkins advises owners to carry their rabbits with care, ensure they are picked up properly and given adequate support, not placed on high tables or sofas, and are not kept in wire or mesh cages, where limbs could get caught.

She adds: "We recommend all rabbits get a minimum of an annual health check to keep an eye on all aspects of their condition and care." 

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