Rabbit Teeth Problems and Diseases
The dentition and gastrointestinal tract of rabbits are highly adapted to the environmental niche occupied by the rabbit in the wild state. Rabbits gain nutrition by ingesting large quantities of vegetation with low energy content. The teeth and their intestines are adapted to the extraction of sufficient nutrients from this diet.
In nature the majority of the diet of a rabbit are grasses. The abrasive nature of this diet is causing rapid wear to the teeth. The rabbit, like other herbivores as well, has adapted to this by evolving teeth that continually erupt to replace the wear. In nature, there is no period when this wear does not occur and no adequate feedback mechanism to regulate the growth of the teeth is in place. Normally there is a finely balanced state of wear and replacement. Any disruption of this balance may lead to dental disease. Commercial rabbit diets may struggle to provide the tooth wear required to balance eruption, as it is less abrasive than the natural diet and of high energy density.
Anatomically and physiologically the oral cavity of the rabbit is very different from that of the small carnivores. Rabbits have four incisors in the upper jaw, with two larger incisors at the side of the lip and two rudimentary behind those (also called peg teeth). This distinguishes rabbits from rodents; the latter only have two incisors. Rabbits do not have canine teeth and a long diastema or gap between the incisors and premolars. The premolars and molars, or cheek teeth, are similar in form and closely abutted together.
Rabbit teeth are classified as a radicular hypsodont. They have no true closed root, allowing eruption throughout life. Rabbits have both deciduous and permanent teeth, but the deciduous teeth are shed within days of birth.
The tips of the upper incisors occlude between the first and second upper incisors. The incisors move in a vertical plane in which the occlusal surfaces move over on another to give a cutting effect. In this position, the cheek teeth are held slightly out of occlusion, since contact would prevent this motion of incisors.
Many of the signs of dental disease are non-specific. Dental disease is so common in pet rabbits that should be included in the list of differential diagnoses for rabbits presenting with any of the following signs: reduced appetite, weight loss, general debility, drooling, discharge from the eyes, facial swelling, hard swelling on the edge of the lower jaw.
Problems with teeth are frequently seen in rabbits, quite often we notice a fracture of one of the incisors.
Problems with teeth are frequently noticed with one or more of the incisor teeth. In our practice, fractured incisors are by far the most common presentation.
Fractures usually occur following nails, traumas to the head or following clipping with nail trimmers. Developmental abnormalities such as the cleft palate and lack of teeth have also been reported but seem to be rare. The development of fewer than normal teeth is more common than a total absence. The lack of peg teeth is common in some breeding lines. Hereditary length mismatch of the upper or lower jaw has been demonstrated to be an inherited defect. Only a small shortening of the upper jaw is already enough to cause severe problems due to malocclusion and overgrowth of the incisors. Incisor malocclusion occurs more often in miniature rabbit breeds and can be seen as early as 4 weeks of age.
If you want to have more information about the tooth trimming of your rabbit please contact the clinic. And learn more about veterinary care for rabbits.
Written by Dr. Metje Zegers, ABVC Senior Veterinarian
