Objective: To assess the heritability of pancreatic acinar atrophy (PAA) in German Shepherd Dogs (GSDs) in the United States.
Animals: 135 GSDs belonging to 2 multigenerational pedigrees.
Procedure: Two multigenerational pedigrees of GSDs with family members with PAA were identified. The clinical history of each GSD enrolled in the study was recorded, and serum samples for canine trypsin-like immunoreactivity (cTLI) analysis were collected from 102 dogs. Dogs with a serum cTLI concentration < or = 2.0 microg/L were considered to have exocrine pancreatic insufficiency (EPI) and were assumed to have PAA.
Results: Pedigree I consisted of 59 dogs and pedigree II of 76 dogs. Serum cTLI concentrations were measured in 48 dogs from pedigree I and 54 dogs from pedigree II. A total of 19 dogs (14.1%) were determined to have EPI, 9 in pedigree I (15.3%) and 10 in pedigree II (13.6%). Of the 19 dogs with EPI, 8 were male and 11 were female.
Conclusions and clinical relevance: Evaluation of data by complex segregation analysis is strongly suggestive of an autosomal recessive mode of inheritance for EPI in GSDs in the United States.