Nutrition and Teeth

Nutrition and Teeth

Dentition and disease

Rabbits have two pairs of incisors on the upper jaw (set one infront of the other) and one pair on the lower jaw. They meet with a chisel action and are essential for nibbling and cutting grass, hay and other long fibre. Set further back in the mouth are several sets of premolar and molar teeth on each jaw surface. The teeth in rabbits grow throughout their lives (incisors grow at 2.4mm per week) and correct occlusion is essential to enable the rabbit to eat and grind its food before swallowing. When malocclusion occurs (failure of the teeth to meet and for the mouth to close, properly) the animal has problems eating. Symptoms of weight loss, failure to groom, increased salivation / dribbling, difficulty to swallow and refusal of certain food types will lead to starvation and death if not rectified. Malocclusion can be of either the premolars / molars or the incisors or both and occurs due to two factors:

Inherited In our experience the dwarf breeds appear to be particularly effected although we have seen it in many other breeds as well. These animals should not be bred from. It usually manifests itself between 6 and 12 months of age.

Nutritional Two factors are essential for good teeth formation and development. Firstly a correct and balanced nutritional supply of calcium, vitamin D and phosphorus. Secondly, access for at least 6 hours per day to grazing of grass and ad lib hay at all times. Again the problem manifests after 6 months of age in most cases.

Treatment

Incisors should be trimmed back to their normal level. This may have to be repeated every 3 to 6 weeks. This can be done at home with a good pair of tooth cutters but a bur drill to cut them off, at your vet, is preferable. This can be done without any sedation.

The ‘cheek teeth’ have to be examined and any sharp edges should be filed back carefully. Overlong molars / premolars produce ulcers in the cheek and on the side of the tongue which are painful. Infection and abscesses commonly occur. If there is any doubt about the severity of the problem, x-ray of the tooth teeth and roots is essential. Distortion of the roots is easily seen and changes in the bone of the jaw may enable dietary changes and antibiotics to improve the situation. We would always do this under a general anaesthetic, as a main blood vessel under the tongue is easily caught and if so, haemorrhage and rapid death occur. Prognosis is poor in the long term as distortion of the teeth tends to worsen with age.

Nutrition and Management

Unfortunately, many owners still keep their rabbits in hutches, often in sheds or garages and away from natural light. To keep your rabbit healthy both physically and mentally we would advise the following dietary / management regime. Weather conditions have to be taken into account (do not leave out in very hot or cold weather!):

Provide an insulated hutch, off the ground with a weather proof sleeping area lined with hay. Clean out all hutch areas regularly. This should be in the shade in the summer and face away from prevailing wind. An area large enough for a toilet and feeding area should be available which can be secured at night time and during bad weather.

The rabbit should have 6 hours minimum access to direct sunlight each day. This ideally would be in the form of an outdoor grass run to allow grazing. The sunlight is important for vitamin D synthesis and tooth and bone formation. This can be portable of connected to the hutch system. Rabbits need exercise to allow for good skeletal development.

The rabbit needs to constantly graze and chew and should have hay available at all times. Hay is the best rabbit bedding as other materials such as shavings may have been treated with preservatives. They require high fibre diets for bowel function.

Rabbit concentrate food should be in the form of a ‘complete’ diet (we use Burgess, supa rabbit excel) where all the nutritional components are mixed in a single pellet type. This includes balanced calcium levels, added vitamins, moderate protein and fibre as well as other nutrients. Rabbits can be ‘selective feeders’ and when fed ‘mixed concentrate rations (contain many types and shapes and often colours of food|), they pick out selected types and do not receive a balanced diet. Rabbits with calcium and fibre deficient diets will develop malformation of their teeth, eye disease (due to blocking of the tear, drainage duct) and weak, malformed bones. Excessive calcium diets can lead to kidney and bladder disease and bladder stones.

Rabbits form two faecal pellet types. 1. Hard dry pellets as an excretory product and 2. Caecotrophs which are green, moist and mucilaginous pellets rich in vitamins and essential bacteria for intestinal function which they eat to maintain hind gut action. If they have bad teeth they do not eat adequate amounts of these caecotrophs.

Points of Interest

If wild rabbits are near to your property vaccinate your rabbit against myxomatosis and viral haemorrhagic disease.
Dandelions have porphyrin pigments which turns rabbit urine pink; it can be confused with blood!