Exploring Causes of Canine Diarrhea

Although diarrhea is a common presentation in dogs, this is the first case-control study of canine diarrhea in which samples were collected contemporaneously from first-opinion practices and screened for a range of pathogens using sensitive molecular techniques. Lifestyle factors, vaccination history, diet, and contact with other species were also evaluated. Data from 86 cases and 167 controls from practices in the UK were included in the final analysis. Multivariable conditional logistic regression showed that dogs were at significantly greater risk for diarrhea if they had recently experienced a change in diet, recently stayed in kennels, scavenged for food, or were fed a home-cooked diet. Up-to-date vaccination history and regular contact with horse feces were associated with a decreased risk for diarrhea; female sex was associated with decreased risk. Only 7% of the samples had evidence of helminth eggs and there was no significant association between the presence of helminth eggs and diarrhea. None of the pathogens tested (eg, enteric coronavirus, parvovirus, distemper, Campylobacter and Salmonella spp) was a significant risk factor for diarrhea. Results suggested that in this predominantly vaccinated population, lifestyle risk factors were more likely to be associated with diarrhea than specific pathogens.

Commentary: The authors identify a potential limitation of this study in that every potential pathogen could not be detected. That said, it is still encouraging to see that this population of dogs had few infectious causes of diarrhea. Many cases of diarrhea remain undiagnosed, so more work is needed in this area. Changing foods and preventing scavenging are 2 practices that should be encouraged to lower the risk for diarrhea.—Patricia Thomblison, DVM, MS

A case-control study of pathogen and lifestyle risk factors for diarrhea in dogs. Stavisky J, Radford AD, Gaskell R, et al. PREV VET MED 99:185-192, 2011.