title: Evaluation of body composition and cartilage biomarkers in large-breed dogs fed two foods designed for growth.
abstract: OBJECTIVE
  To evaluate cartilage and bone biomarkers and body composition in growing large-breed dogs consuming a diet designed for growth.
  
  
  METHODS
  43 large-breed 2 month-old-puppies.
  
  
  METHODS
  Dogs were randomly assigned to receive 1 of 2 foods until 18 months of age. Dogs were evaluated at 2, 5, 12, and 18 months of age via dual energy x-ray absorptiometry (DEXA), CBC, serum biochemical profile, and concentrations or activities of taurine, vitamin E, fatty acids, glutathione peroxidase, C-propeptide of type II collagen (CPII), cartilage oligomeric matrix protein (COMP), carboxy-terminal cross-linked fragment of type II collagen (CTXII), bone specific alkaline phosphatase (BAP), osteocalcin, ghrelin, and growth hormone.
  
  
  RESULTS
  Blood components largely reflected the composition of the foods. Dogs fed the food with a higher concentration of protein, calcium, n-3 fatty acids, and antioxidants had a lower percentage of body fat and greater percentage of lean body mass at 5, 12, and 18 months of age, and higher CPII:CTXII ratio and lower COMP at 18 months of age. The BAP activity, osteocalcin concentration, and CTXII concentration declined with age, whereas COMP concentration and CPII concentration were similar at all time points for both foods.
  
  
  CONCLUSIONS
  The BAP activity, osteocalcin concentration, and CTXII concentration were greater during growth than at 18 months of age. The food that was proportionately higher in protein, calcium, n-3 fatty acids, and antioxidants increased lean body mass and may have positively affected cartilage turnover as maturity was attained. Whether the rate of cartilage turnover during growth affects development of orthopedic disease or arthritis in adulthood has yet to be determined.
authors.affiliation: Hill's Pet Nutrition Incorporated, Pet Nutrition Center, Topeka, KS 66601, USA.
authors.forename: William D
authors.initials: WD
authors.lastname: Schoenherr
authors.forename: Jennifer M
authors.initials: JM
authors.lastname: Macleay
authors.forename: Ryan M
authors.initials: RM
authors.lastname: Yamka
mesh_terms: D015502:Absorptiometry, Photon; D000469:Alkaline Phosphatase / Q000097:blood / Q000378:metabolism; D000821:Animal Feed; D000818:Animals; D015415:Biomarkers / Q000097:blood; D001774:Blood Chemical Analysis / Q000379:methods / Q000662:veterinary; D001823:Body Composition; D049628:Body Size; D001846:Bone Development; D001842:Bone and Bones / Q000378:metabolism; D002356:Cartilage / Q000254:growth & development / Q000502:physiology*; D004285:Dogs / Q000033:anatomy & histology*; D005260:Female; D054439:Ghrelin / Q000097:blood; D005979:Glutathione Peroxidase / Q000097:blood; D013006:Growth Hormone / Q000097:blood; D008297:Male; D015675:Osteocalcin / Q000097:blood / Q000378:metabolism; D013654:Taurine / Q000097:blood
chemical_list: D015415:Biomarkers; D054439:Ghrelin; D015675:Osteocalcin; D013654:Taurine; D013006:Growth Hormone; D005979:Glutathione Peroxidase; D000469:Alkaline Phosphatase