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
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 trypsinlike
immunoreactivity (cTLI) analysis were collected
from 102 dogs. Dogs with a serum cTLI concentration
≤ 2.0 µg/L were considered to have exocrine pancreatic
insufficiency (EPI) and were assumed to have
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.
Conclusion 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.
(Am J Vet Res 2002;63:1429–1434)