Proliferative Enteropathy in Rabbits: Lawsonia Infection and Diarrhea

Proliferative enteropathy is a disease of the intestines caused by Lawsonia intracellularis, a bacterium that lives inside intestinal cells. In rabbits, it is associated with abnormal thickening and overgrowth of the intestinal lining, especially in the lower small intestine and nearby bowel. That change can interfere with normal digestion and absorption, leading to diarrhea, weight loss, dehydration, and poor body condition.

This condition is considered uncommon in pet rabbits compared with more routine causes of diarrhea, such as diet imbalance, coccidia, or general gastrointestinal upset. Still, it is a real disease that has been documented in rabbits, including colony outbreaks and confirmed tissue infections. Because rabbits can become critically ill from fluid loss and reduced food intake, suspected intestinal disease should never be watched at home for long without veterinary guidance.

For pet parents, the most important point is that proliferative enteropathy is not something you can identify by symptoms alone. Many rabbit intestinal problems look similar at first. Your vet will need to sort out whether Lawsonia, parasites, diet-related dysbiosis, or another infection is the more likely cause.

The underlying cause is infection with Lawsonia intracellularis. This bacterium infects intestinal crypt cells and triggers those cells to multiply abnormally, which thickens the intestinal lining and reduces normal absorptive function. In practical terms, that means the bowel becomes less efficient at handling nutrients and fluid, so affected rabbits may develop diarrhea, weight loss, and dehydration.

The organism is thought to spread mainly by the fecal-oral route. That means contaminated feces, soiled housing, shared equipment, and crowding can all raise risk. Research and laboratory animal resources also suggest that colony settings, stress, and exposure to infected animals or contaminated environments may play a role in transmission.

It is also important to remember that not every rabbit with diarrhea has Lawsonia. VCA notes that rabbit diarrhea has many possible causes, including low-fiber or high-carbohydrate diets, rapid diet changes, bacterial or parasitic disease, toxins, and inappropriate oral antibiotics. Your vet may need to rule out coccidia, dysbiosis, and other enteric disease before deciding whether proliferative enteropathy is likely.

Diagnosis starts with a careful history and exam. Your vet will ask about your rabbit’s age, diet, recent stress, new rabbits in the home, stool changes, appetite, and weight trend. Because diarrhea in rabbits has many causes, the first step is often ruling out more common problems such as coccidia, diet-related gastrointestinal imbalance, or generalized bacterial enteritis.

Initial testing often includes a fecal exam, hydration assessment, and sometimes blood work to look for dehydration, protein loss, or other signs of systemic illness. Depending on the case, your vet may also recommend abdominal imaging to assess gut contents, intestinal gas, or other complications.

Confirming Lawsonia intracellularis can be challenging. The organism does not grow on routine culture media, and published rabbit cases have relied on PCR testing of feces or intestinal tissue, plus histopathology or special staining of affected intestine. In many pet rabbits, your vet may make a working diagnosis of infectious enteritis and begin treatment while pursuing the most practical tests available.

Prevention focuses on lowering exposure to infectious stool and supporting a healthy gut. Keep housing clean and dry, remove soiled bedding promptly, wash food and water containers regularly, and avoid overcrowding. If you bring home a new rabbit, quarantine first and ask your vet about a safe introduction plan, especially if any rabbit has diarrhea or poor appetite.

Diet matters too. VCA notes that rabbits are prone to intestinal problems when diets are too high in carbohydrates and too low in fiber. A hay-based diet, gradual food changes, and avoiding unnecessary oral antibiotics can help protect normal gut function. Good sanitation and good nutrition work together.

There is no routine pet-rabbit vaccine used for Lawsonia intracellularis. If your rabbit has diarrhea, early veterinary care is one of the best prevention tools because it reduces the chance of dehydration, gut stasis, and spread to other rabbits in the household or colony setting.