title: A longitudinal study of the influence of lifetime food restriction on development of osteoarthritis in the canine elbow.
abstract: OBJECTIVE
  To report the effects of age and lifetime calorie restriction on development and progression of osteoarthritis (OA) in elbow joints of Labrador retrievers.
  
  
  METHODS
  Longitudinal cohort study.
  
  
  METHODS
  Labrador retriever dogs (n=48).
  
  
  METHODS
  Puppies from 7 litters were allotted to 2 groups of 24 dogs each. Diet-restricted (DR) dogs received 25% fewer calories than control-fed (CF) pair mates. Elbow radiographs were taken at 6 and 8 years of age and end of life (EOL). Gross and histopathologic evaluations for OA occurred at EOL.
  
  
  RESULTS
  There was no statistical difference in radiographic OA frequency between groups at any of the time points. Radiographic OA severity was greater for CF dogs at 6 years only (P<.05). There was no significant difference between feeding groups for histopathologic prevalence or severity of OA. Similarly, there were no differences in gross OA lesions between the groups (P>.05). Fragmented medial coronoid process, un-united anconeal process, and osteochondrosis were not present in any elbow.
  
  
  CONCLUSIONS
  No differences in prevalence or severity of radiographic and histopathologic elbow OA were found between feeding groups. Diet restriction resulted in a 1.8-year extension in median lifespan but no additional incremental worsening of elbow disease. Evaluation at time points <6 years may have revealed larger differences in OA prevalence and severity between the dietary groups.
  
  
  CONCLUSIONS
  These findings support calorie restriction as a clinical tool to slow progression of elbow OA.
authors.affiliation: Department of Clinical Studies, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, USA. jhuck@mail.vetmed.lsu.edu
authors.forename: Jennifer L
authors.initials: JL
authors.lastname: Huck
authors.forename: Daryl N
authors.initials: DN
authors.lastname: Biery
authors.forename: Dennis F
authors.initials: DF
authors.lastname: Lawler
authors.forename: Thomas P
authors.initials: TP
authors.lastname: Gregor
authors.forename: Jeffrey J
authors.initials: JJ
authors.lastname: Runge
authors.forename: Richard H
authors.initials: RH
authors.lastname: Evans
authors.forename: Richard D
authors.initials: RD
authors.lastname: Kealy
authors.forename: Gail K
authors.initials: GK
authors.lastname: Smith
mesh_terms: D000818:Animals; D001835:Body Weight; D001848:Bone Diseases, Developmental / Q000662:veterinary; D015331:Cohort Studies; D004038:Diet, Reducing / Q000662:veterinary*; D004283:Dog Diseases / Q000517:prevention & control*; D004285:Dogs; D010003:Osteoarthritis / Q000517:prevention & control / Q000662:veterinary*