Diarrhea in Ferrets
Dr. Barb Oglesbee
Diarrhea occurs when the intestinal tract is unable to absorb fluid or when cells lining the intestines secrete excessive amounts of fluid. Many factors can alter the intestinal tract's ability to absorb or secrete fluids properly. For example, if food is not properly digested, it tends to pull fluid into the intestinal lumen. Or if the lining of the intestinal tract is irritated by a toxin, infection or irritation, cellular changes cause an increase in secretion of fluid into the intestinal lumen. Bacterial infection. Bacterial infections are among the most common causes of diarrhea in ferrets. Bacteria may infect the stomach, small intestine or large intestine. Helicobacter mustelae is an extremely common cause of stomach ulcers, causing melena (digested blood in the feces) and sometimes diarrhea. Campylobacter spp., Salmonella sp., Clostridium spp., and Desulfovibiro are common bacteria that cause disease in the intestines.
Peristaltic waves, which are rhythmic contractions of the intestinal tract that serve to push digested food forward, occur at regular controlled intervals in normal ferrets. In some ferrets with diarrhea, these waves lack coordination, so that food moves through the intestinal tract too quickly. This results in an increase in frequency of defecation, and an increase in the liquid content since fluid does not have a chance to be absorbed.
Ferrets may normally have an occasional stool that is not well formed. This can occur due to excitement, stress or sudden changes in the diet. For example, diarrhea may occur if the ferret is fed excessive numbers of treats or table foods, or if he eats spoiled food from the garbage. If due to a diet change, the diarrhea should resolve after all new food is digested, and should not last more than 12 hours after new food has been removed from the diet. If the diarrhea persists, or if the ferret develops any other symptoms such as vomiting, lethargy, excess drooling, pawing at the mouth or decrease in appetite, you should seek veterinary attention immediately.
The appearance of the stool often varies depending on the area of the intestinal tract that is damaged. For example, ferrets with a disorder of the large bowel (colon) will usually have diarrhea that is characterized by frequent, painful defecations in which only a small amount of stool is produced. Stool is liquid or has a formed but soft consistency, and may contain fresh blood or mucus. Rectal prolapse may be a sequela to chronic large bowel diarrhea.
Ferrets with diarrhea due to small intestinal disorders often produce a large volume of feces with each defecation. Stools often have a liquid consistency. If the small intestine is damaged and can no longer absorb nutrients properly, stools often have a grainy, or "bird seed" appearance. Ferrets with small intestinal diarrhea often lose weight despite having a good appetite.
There are many causes of diarrhea in ferrets. The cause may be very simple, such as a dietary change, or may be due to a number of complex disease processes. There are many contagious diseases that cause diarrhea, so it is important to inform your veterinarian of any potential contact – direct or indirect – with other ferrets.
Viral infection. Epizootic catarrhal enteritis (ECE) is commonly known as "green slime disease" because of the characteristic green, mucous covered diarrhea produced by affected ferrets. The specific virus causing this disease has not yet been isolated. The disease appears to be highly contagious, and is usually spread by young asymptomatic carriers, which means they shed the virus without showing any symptoms. Other, less common causes of diarrhea include rotavirus and parvovirus (Aleutian disease virus, not canine parvovirus).
Parasitic causes. Intestinal worms are rare. However, microscopic parasites, such as Giardia, Coccidia and Cryptosporidium are common causes of diarrhea in ferrets. These parasites are more likely to contribute to diarrhea when a bacterial or viral infection is also present.
Neoplasia. Cancer, especially lymphoma, is extremely common in ferrets of all ages. Lymphoma may cause diarrhea by invading the intestinal tract or liver. Primary cancers of the gastrointestinal tract, such as adenocarcinoma, are less common neoplastic causes of diarrhea.
Obstruction. Tumors or foreign objects may block the intestinal tract. Ferrets are extremely fond of chewing and often swallow toys. Most ferrets with intestinal obstruction have vague symptoms such as weight loss, lack of appetite and diarrhea. Occasionally, an intestinal intussusception, which is telescoping of one part of the intestinal tract into another, may cause diarrhea initially, then a lack of feces later in the course of disease.
Infiltrative Disease. Eosinophilic gastroenteritis is a condition in which eosinophils (a type of white blood cell whose normal function is to fight infection) invades the intestinal tract. The cause of this disorder is unknown. Proliferative bowel disease is a condition in which lymphocytes and plasmacytes invade the large intestine. This disease is caused by a bacteria (Desulfovibiro).
Drugs and toxins. These include plant toxins, heavy metal toxicity, and bacterial toxins from spoiled food.
Metabolic disorders. These conditions include liver disease, kidney disease and pancreatic disease.
Dietary. These include diet changes, eating spoiled food and dietary intolerance.
Stress induced. This might be caused by a sudden change in environment.