Updated project metadata. In small animals, diarrhoea is a regular presentation, the aetiology of which can be varied, from an isolated self-limiting event to more serious episodes requiring symptomatic and supportive treatment. Chronic diarrhoea, defined as diarrhoea lasting longer than 3 weeks, is a relatively common problem often prompting referral for more detailed investigation. Although the potential cause of chronic diarrhoea includes chronic intestinal parasitism and alimentary neoplasia (specifically lymphoma), the majority of these dogs will be diagnosed with idiopathic canine chronic enteropathy (CCE), previously referred to as idiopathic inflammatory bowel disease (IBD). Of those cases diagnosed with CCE, further subdivision based on response to treatment trials leads to a final diagnosis of antibiotic responsive diarrhoea (ARD), food responsive diarrhoea (FRD) or idiopathic inflammatory bowl disease (IBD). The aim of this study was to compare the proteomes of faeces of dogs with chronic enteropathies and a population of healthy dogs, and furthermore to identifying proteins that might be useful in distinguishing FRD from ARD from IBD.