Objective: To assess the clinical accuracy of 2 serum-based assays and 1 saliva-based assay for detection of adverse food reaction (AFR) in dogs without clinical signs of disease.
Animals: 30 healthy client-owned dogs.
Procedures: Dog owners completed an online survey to collect comprehensive information about their pets' diet history. From each dog, serum and saliva samples were obtained and submitted for AFR testing by means of 3 assays that assessed the immunoglobulin response to 24 foods. Assays A and B measured food allergen-specific IgE concentrations in serum, whereas assay C measured food allergen-specific IgA and IgM concentrations in saliva. Descriptive data were generated, and Fisher exact tests were used to assess the respective associations between positive test results and specific food ingredients to which dogs were exposed.
Results: Assays A, B, and C yielded positive results for 26, 18, and 30 dogs, respectively. All dogs had positive results for at least 1 assay. The median (range) number of foods or ingredients to which dogs tested positive was 10.5 (0 to 24) for assay A, 1 (0 to 13) for assay B, and 12.5 (4 to 22; IgM) and 3 (0 to 24; IgA) for assay C. Positive test results were not significantly associated with prior food exposure.
Conclusions and clinical relevance: Saliva and serum assays for AFR often yielded positive results for apparently healthy dogs and are not recommended for clinical use. Elimination diet trials remain the gold standard for diagnosis of AFR in dogs.