Gastrointestinal stasis (or G.I. stasis) is a serious and potentially fatal condition that occurs in some rabbits in which gut motility is severely reduced and possibly completely stopped. Treatment should be sought immediately from a veterinarian specializing in exotic animals and with significant rabbit experience. When untreated or improperly treated, G.I. stasis can be fatal in as little as 24 hours.

G.I. stasis is the condition of food not moving through the gut as quickly as normal. The gut contents may dehydrate and compact into a hard, immobile mass (impacted gut), blocking the digestive tract of the rabbit. Food in an immobile gut may also ferment, causing significant gas buildup and resultant gas pain for the rabbit.

The first noticeable symptom of G.I. stasis may be that the rabbit suddenly stops eating. Treatment frequently includes subcutaneous fluid therapy (rehydration through injection of saline solution under the skin), drugs for treatment of the buildup of gas in the digestive tract, massage to promote gas expulsion and comfort, possible drugs to promote gut motility, and careful monitoring of all inputs and outputs. The rabbit's diet may also be changed as part of treatment.

Some rabbits are more prone to G.I. stasis than others. The causes of G.I. stasis are not completely understood, but common contributing factors are thought to include:

• a lack of fiber in the diet. Many pet rabbits do not get sufficient fresh grass hay but are instead mistakenly fed only commercial alfalfa pellets originally developed for rapidly increasing mass in rabbits bred for meat.

• insufficient moisture in the diet. Fresh, leafy greens are a critical part of a rabbit's diet in part because of their moisture content, which helps prevent the gut contents from becoming impacted.

• lack of exercise. Rabbits confined to a cage frequently do not get the opportunity (or motivation) to run, jump, and play which is critical in maintaining gut motility.

In addition, G.I. stasis can be caused by the rabbit not eating for other reasons, such as stress, dental problems, or other unrelated health problems.

G.I. stasis is sometimes misdiagnosed as cat-like "hair balls" by veterinarians not familiar with rabbit physiology.