True diarrhea (unformed, watery feces) is relatively rare in adult rabbits. It can be caused by intestinal parasites, such as coccidia (Eimeria spp.), roundworms, tapeworms, or anything that inflames the intestinal lining. Your rabbit-experienced veterinarian will be able to examine a fecal sample (you should probably provide the vet with a bit both fecal and cecal pellets) to examine them for signs of parasitic infection.

True diarrhea is more common in baby rabbits. One of the most common causes is coccidia, and if you see runny stool in your baby rabbit, you must get him to the vet as soon as possible for treatment. In a baby rabbit, dehydration caused by diarrhea can rapidly result in death. It is wise to consider runny stool in a baby rabbit a true emergency.

The cecum is a delicately balanced ecosystem. If the intestine is moving too slowly, or if the rabbit is getting a diet too rich in digestible carbohydrates and too low in crude fiber, the complex population of bacteria in the cecum can become "unbalanced." This condition, known as CECAL DYSBIOSIS. Simply put, cecal dysbiosis means that the beneficial bacteria (e.g., Bacteroides spp. and a variety of others) are outcompeted and outnumbered by less desirable inhabitants such as yeast (a fungus, usually Saccharomycopsis sp.) or even very harmful bacteria such as Clostridium spp., related to the ones that cause tetanus and botulism.

A rabbit suffering from cecal dysbiosis will produce cecotropes that are mushy, pasty or even liquid. They are usually quite foul-smelling, and often stick to the bunny's back end in great, nasty clumps. These unformed cecotropes are not a primary disease, however. They are a symptom of a disorder somewhere in the bunny's system. In order to cure the runny stool problem, the underlying cause must be addressed.

The Causes of Runny Stool in Baby Rabbits

If the bunny suffering from runny stool is a baby, how old is he? If younger than eight weeks, and not nursing, his runny stool problem may be due to his being weaned too young. Many pet stores will (illegally) sell rabbits younger than eight weeks of age (and some as young as four weeks!), because that is when they are still "cute" and more apt to be purchased on a whim. Sadly, many of these babies will succumb to intestinal disorders.

Unlike most mammals, baby rabbits have a sterile lower intestine until they begin to eat solid food at the age of 3-4 weeks. It is during this time that their intestines are at their most critical phase, and the babies need their mother's milk, which changes pH and provides vital antibodies that help the baby gradually adjust to his changing intestinal environment. Without mother's milk, a baby starting to eat solid food is highly susceptible to enteritis (inflammation of the intestinal lining), which can cause fatal diarrhea.

At the first sign of runny stool in a baby rabbit, off to the vet! Treatment for diarrhea in baby rabbits will probably include subcutaneous fluid thereapy, and administration of oral probiotics. Lactobacillus acidophilus powder (NOT yogurt, which can make the problem worse) suspended in clean drinking water and carefully administered via syringe seems to help foster a healthy intestinal environment and may even soothe intestinal inflammation. A very small amount of a clay-based product such as Kaopectate can help solidify the stool and stop the cycle.

As mentioned before, coccidial infection is very common in some areas, and some vets will simply treat a baby rabbit's diarrhea as coccidia, even without a fecal test. Common antibiotics used to treat coccidia include Albon and the potentiated sulfas, such as Trimethoprim Sulfa (TMZ) or Bactrim.

1. Mechanical Problems

• Obesity
  Is the bunny with mushy stool stuck to his bottom obese? If so, the cecotropes could be normal, but he can't reach them as they are produced, and so smears them all over his bum in trying to reach them. Calorie reduction (first step: remove commercial pellet food and any starchy treats, replacing them with fresh, fragrant herbs) and exercise are in order.

• Arthritis
  Similarly, a rabbit who is suffering from degenerative joint problems in the spine, hips, or other areas, may not be able to reach his cecotropes easily. He ends up sitting on some of them, and squashing them into his fur. Arthritis can be treated by your veterinarian, who may prescribe a non-steroidal anti-inflammatory drug (NSAID) such as Rimadyl (carprofen) or Meloxicam, though all the usual cautions for use of NSAIDS apply.

2. Dietary Problems

• Starch-rich Diet
  Rabbits, like horses and cattle, are strict herbivores. The rabbit intestine--and its normal bacterial flora--has evolved to feed almost exclusively on grass and herbs. >br> Does your rabbit get starchy treats such as oatmeal, crackers, bread or sweets? Some rabbits with very sensitive intestines can suffer from runny cecotropes even from being fed commercial pellets. Fruit, as healthy as it is for humans, can be too much of a good thing for rabbits. The high level of sugar and starch in table fruit makes them too rich for a bunny except as a very small, occasional treat. A diet too rich in digestible starch is one of the most common causes of runny cecotropes in companion rabbits.

• Fiber-poor Diet
  A rabbit should be fed unlimited grass hay, such as timothy, brome, wheat or oat. DO NOT use alfalfa, as this is far too rich in calories and protein for good rabbit health. If a rabbit does not get unlimited grass hay to nibble on throughout the day, the muscles of the intestine may become flabby, and the normal peristalsis (muscular movements that push food through the gut) will become sluggish. This causes the passage of food through the cecum to be too slow to properly "flush" the bacterial populations, and cecal dysbiosis can result. The high fiber content of grass hay also helps to "dilute" the starch of other dietary items, and helps to provide a healthy intestinal environment. In preventing and curing a runny stool problem, it is very important to provide a complete and healthy diet.

When a rabbit is ill, in pain, or is suffering from emotional stress, the most common physiological response is a slowing of the normal peristaltic movements of the intestine. This results in cecal dysbiosis, with all the accompanying problems of runny stool, and possible inflammation of the intestinal lining (enteritis).

Some of the most common causes of intestinal slowdown (and hence, cecal dysbiosis) in rabbits include

• Dental Problems
• Urinary tract disorders
• Upper respiratory infections
• "Head tilt"

  These must be diagnosed and treated by a veterinarian who is familiar with such problems and knows how to deal with them. The best way to solve the runny stool problem is to address the underlying health disorder, even if it requires that your vet take blood for a complete blood chemistry and blood count, or a sample of infected material for culture and sensitivity testing.

  Once the underlying problem is treated, the runny stool often resolves on its own. If the condition is not treated, it can progress to something worse, and eventually result in a potentially life-threatening condition, ILEUS, in which the intestines stop completely, the bunny stops eating and stops producing any fecal pellets or normal cecotropes. If not treated, this condition is almost invariably fatal.

While you and your veterinarian are treating the problems that caused the runny stool, it's still important to keep the bunny clean and comfortable. Dried cecotropes stuck to the rear end are not only smelly and uncomfortable, they also attract flies, and can result in a life-threatening fly strike.

To prevent this, be sure to learn how to give your bunny a "butt bath"--SAFELY.

As you can see, the appearance of runny stool in a rabbit is not always a simple matter. It may require dietary changes, good husbandry, and sometimes extensive diagnostic work and treatment by your veterinarian. But it will all be worth it for a long life filled with happy, nose-wiggling love.