Objective—To determine in dogs what effect using
hip conformation scores assigned by the Orthopedic
Foundation for Animals (OFA) as a criterion for breeding
selections would have on hip conformation scores
of the progeny.
Animals—English Setters, Portuguese Water Dogs,
Chinese Shar-peis, and Bernese Mountain Dogs for
which OFA hip conformation scores were known.
Procedure—Pedigree data were obtained from the
national breed clubs and the American Kennel Club and
merged with data from the OFA hip conformation score
database. An ANOVA was used to evaluate the effects
of sex, age at the time of radiographic evaluation, and
year of birth on the variation in hip conformation scores
among the progeny. Heritability was estimated by use
of within-year midparent offspring regression analyses.
Results—Significant differences in progeny hip conformation
scores between sexes were not detected,
but age at the time of radiographic evaluation and year
of birth had a significant effect on hip joint conformation
of the progeny. Estimated heritability (mean ± SE)
was 0.26 ± 0.03, and dam and sire hip conformation
scores had a significant effect on progeny hip conformation
scores. Annual decreases in percentage of
dysplastic progeny and increases in percentages of
progeny and breeding dogs with phenotypically normal
hip joint conformation were detected.
Conclusions and Clinical Relevance—Results indicated
that hip conformation scores have moderate
heritability in dogs and selection of breeding stock
with better hip conformation scores will increase the
percentage of progeny with phenotypically normal hip
joint conformation. (J Am Vet Med Assoc 2000;