For many years, it was thought that rabbits commonly developed hairballs (also called trichobezoars) because they are fastidious groomers. It was thought that hairballs were the main reason that a rabbit would not want to eat and would not pass stool. While hair accumulations in the stomach may occur when the hair mats together with food, rabbits normally have some amount of hair in their stomachs that does not typically cause any problems.
Veterinarians now know that rabbits that are not eating have developed gastrointestinal (GI) stasis. GI stasis is the slowing of passage of food through the GI tract. This condition may be due to a change in the population of bacteria normally living in the GI tract that ferment (digest) rabbit's food; it may be due to a true outflow obstruction caused by hair or other foreign material; or it may be secondary to a neurological disorder caused by Encephalitozoon cuniculi.
What causes GI stasis in rabbits?
Rabbits stop eating for several reasons. They may become sick with other diseases, such as dental problems or kidney disease, which commonly cause a decreased appetite. They also often stop eating when they are stressed, overheated, in pain from injuries or arthritis, or uncomfortable from other gastrointestinal problems such as bacterial, viral, or parasitic intestinal infections.
"Regardless of why they stop eating initially, rabbits that do not eat undergo a pH change in their GI tracts that favors the growth of gas-producing bacteria."
Some rabbits get GI upset when they are eating too much carbohydrate (e.g., pellets, treats, carrots, fruit) and not enough fiber (e.g., hay). Regardless of why they stop eating initially, rabbits that do not eat undergo a pH change in their GI tracts that favors the growth of gas-producing bacteria. When these bacteria proliferate, they produce painful gas that makes the rabbit want to eat even less. These bacteria also may produce toxins that, if untreated, not only make the rabbits feel sicker, but also lead to organ failure and death. E. cuniculi is a microsporidian parasite that can infect the spinal cord and subsequently causes poor contractility of the stomach, which may result in GI stasis.
How will my veterinarian diagnose GI stasis?
Your veterinarian will ask you a series of questions about your rabbit's signs and behavior, and then perform a complete physical examination on your rabbit, as well as tests such as X-rays and bloodwork to evaluate your rabbit's overall health. Rabbits with GI stasis often look bloated and are passing little to no stool. X-rays often reveal a gas-filled stomach and, in many cases, a gas-filled cecum (large intestine), too.
Blood tests often reveal abnormal electrolyte values and evidence of dehydration. There may also be changes associated with underlying diseases, such as kidney or liver disease. An examination of your rabbit's mouth may show sharp points on the teeth, causing discomfort upon chewing, or evidence of a dental abscess (infection).
How will my veterinarian treat GI stasis?
Once your veterinarian confirms that your rabbit has GI stasis and determines the underlying cause for why your rabbit has stopped eating, supportive treatment will be recommended. Depending on the rabbit’s condition, hospitalization may be recommended. Therapy for GI stasis may include any of the following:
- fluid therapy for rehydration
- nutritional support (syringe feeding if not eating)
- antibiotics if there is an underlying bacterial infection
- pain relievers
- anti-inflammatory medications to help with stomach pain
- motility-modifying drugs to enhance movement of food through the stomach and intestines (only used when the rabbit can produce fecal material)
How can I keep my rabbit from getting GI stasis?
The best way to prevent GI stasis from developing is to feed your rabbit a high-fiber, hay-based diet with supplemental vegetables, a small amount of pellets, and very limited amounts of fruit (limited because as it is high in carbohydrates). The high fiber in hay stimulates normal intestinal motility and helps wear down rabbits’ continuously growing teeth, thereby reducing the likelihood of dental problems.
You should allow your rabbit lots of supervised, out-of-cage time to encourage physical exercise, which promotes normal gut motility. Prevent your rabbit from chewing on rugs, towels, or other material that may cause a true, life-threatening physical obstruction in your rabbit's GI tract.
You can also help your rabbit avoid GI stasis by having them checked regularly by your veterinarian, who can monitor for other underlying diseases that may contribute to the development of GI stasis.
Finally, you can watch your rabbit carefully at home for signs such as decreased appetite, reduced stool formation, or any other abnormal behaviors and have them checked immediately by your veterinarian if any of these signs occur. A rabbit that is not eating can progress from just feeling poorly to developing a life-threatening illness in a matter of hours.