Anatomy and Physiology of the Rabbit and Rodent Gastrointestinal System

Rabbits, guinea pigs, and chinchillas are all classified as hindgut fermenters, depending on primarily cecal microflora for nutrient composition. The rabbit has some unique anatomical features including the sacculus rotundus and the vermiform appendix. Gastrointestinal disorders in these animals can be a challenge to clinicians as not only the motility of the hindgut must be maintained, but the microflora as well. Dysbiosis, or changes in the microflora can release toxins and further alter the pH, microflora and motility. The clinician must also be aware of gastrointestinal pain and hydration status accompanying most gastrointestinal disease. The Rabbit Gastrointestinal System Although dental health and thorough examination of the teeth should always be included in the physical examination of a rabbit presented with suspected digestive system disease, this discussion will concentrate on the gastrointestinal system. Nutrition plays an important role in the functioning of the rabbit digestive system and will be discussed as it pertains to the gastrointestinal anatomy, physiology, and major disease syndromes. Rabbits are true non-ruminant herbivores. Their digestive reservoir permits and increases the efficiency of utilization of fibrous diets. They have a large stomach and well-developed cecum relative to other non-ruminant herbivores such as the horse.