Diarrhea in collective kennels

Diarrhea is one of the most frequently reported concerns in kennels. Diarrhea is not a disease; it is only a sign that can have several infectious and non-infectious etiologies. When diarrhea occurs chronically it is very important to identify those causes, especially in the case of kennel medicine. The pathophysiology of diarrhea is complex and can include changes in peristalsis, increased digestive gland secretions, or decreased absorption. The clinical form of diarrhea depends on the localization of the pathology. Small bowel diarrhea induces watery stools with an increase in volume, sometimes with melena, and can be associated with weight loss when chronic. Large bowel diarrhea yields soft, but rarely watery, stools with mucus and blood, often with an increased frequency of defecation. In kennels it is very important to know if coprophagia is associated with diarrhea. Coprophagia is rarely due to a nutritional deficiency but more likely related to poor digestive capabilities, so it is usually associated with small bowel diarrhea. In kennel populations, diarrhea is often due to a combination of several causes: viruses, bacteria, parasites and the environment. It is difficult to study all the potential causes, so we focus on only a few of them. Gastrointestinal viruses are the most frequently encountered viruses in kennels, including Canine Parvovirus type 2 (CPV-II) and Canine Coronavirus (CCV). These viruses are very complementary: CPV-II attacks cells with high replication levels (digestive cells from crypts), and CCV attacks mature cells (digestive cells located on the apex of villosities). These complementary pathogeneses explain why the combination of these viruses often cause fatal diarrhea in puppies during weaning. Protozoa are one-cell organisms and include the gastrointestinal parasites Isospora sp. and Giardia duodenalis. These two parasites are frequently found in kennels because they are almost impossible to eradicate since they are so difficult to cure in infected dogs. Isospora sp. causes mixed (small and large) bowel diarrhea exclusively in puppies during weaning (diarrhea with mucus and blood, often associated with variation in weights within the litter). G. duodenalis is the most frequent parasite in kennels and it can induce small bowel diarrhea in puppies and in adult dogs. Diarrhea due to G. duodenalis is most often recurrent rather than chronic. The principal environmental causes of diarrhea in kennels are stress and overfeeding. Overfeeding can be managed by using a high quality food with a high caloric level to decrease the quantity given each dog per day. Some other strategies can be applied such as bowls designed to decrease the speed of ingestion. Stress is not always easy to manage, especially in working dogs kennels. Different methods of control include: kennel design, nutritional support to help to decrease effects of stress, and management of post-effort. There is no miracle solution. The first step is to diagnose the cause of the diarrhea: stool samples can be examined to check for parasites or the presence of viral DNA and ELISA can be used to detect G. duodenalis. The design of the kennel and feeding practices will need scrutiny as well. After identification of the cause, the attending veterinarian can employ sanitary and medical preventive measures to better control recidivism. Diarrhea in kennels is often due to parasites. The old proverb: “When you breed dogs, you breed parasites!” also applies to working dog kennels. It is very important to carry out regular fecal tests to identify the parasitism level in the kennel as these will help the veterinarian to choose the right treatment strategy. Other interventions that can be applied include supporting digestive function by manipulating nutrition with tailor-made diets and changing kennel design and genetic selection to decrease stress.