Altered serum
cobalamin concentrations have been observed in dogs with
gastrointestinal disorders such as
exocrine pancreatic insufficiency (EPI) or gastrointestinal
inflammation. The aims of the current study were 1) to identify breeds with a higher proportion of dogs with a decreased serum
cobalamin concentration, 2) to determine whether dogs with such decreased concentrations tend to have serum canine
trypsin-like immunoreactivity (cTLI) concentrations diagnostic for EPI, and 3) to compare the number of submissions for serum
cobalamin analysis by breed to the American Kennel Club (AKC) breed ranking list of 2009. In this retrospective study, results of 28,675
cobalamin tests were reviewed. Akitas, Chinese Shar-Peis, German Shepherd Dogs, Greyhounds, and Labrador Retrievers had increased proportions of serum
cobalamin concentrations below the lower limit of the reference interval (<251 ng/l; all P < 0.0001). Akitas, Chinese Shar-Peis, German Shepherd Dogs, and Border Collies had increased proportions of serum
cobalamin concentrations below the detection limit of the assay (<150 ng/l; all P < 0.0001). Akitas, Border Collies, and German Shepherd Dogs with serum
cobalamin concentrations <150 ng/l were more likely to have a serum cTLI concentration considered diagnostic for EPI (≤2.5 µg/l; all P ≤ 0.001). The breed with the highest proportion of samples submitted for serum
cobalamin analysis in comparison with the AKC ranking list was the Greyhound (odds ratio: 84.6; P < 0.0001). In Akitas and Border Collies, further investigations are warranted to clarify if a potentially breed-specific
gastrointestinal disorder is responsible for the increased frequency of decreased serum
cobalamin and cTLI concentrations.