There are 3 main sources for joint problems in Labs -- Congenital (hereditary), Developmental (e.g., improper diet or exercise), and Trauma.
My opinion is that the consensus of scientific nutritional studies shows that a proper balance of calcium and other minerals along with the proper density of metabolizable energy (kcals) such as is found in typical Large Breed Puppy formulas leads to reducing Developmental improper diet as a cause of later joint problems.
In a recent (11-03) LC thread on using puppy food vs. adult food: https://www.justlabradors.com/forum/i...c,88374.0.html I advocated for feeding a Large Breed Puppy food for the first 12 months, saying that it helped reduce the incidence of joint problems in Labs and, since 1 in 3 Labs develop joint problems, it's best to reduce early developmental diet as a potential cause.
Luvmydogz2much (quite appropriately) asked what my source was for that ratio.
I searched but couldn't find the exact reference; BUT there are ample veterinary medicine scientific studies on the incidence of the various joint problems (congenital, idiopathic, HOD, HCD, Pano) in Labs of which those below are representative; possibly 1 in 3 (33%) may even be slightly low:
Bone dysplasias in the labrador retriever: a radiographic study by JP Morgan, A Wind, and AP Davidson
A radiographic study of the humeral head, elbow joint, hip joint, stifle joint, tarsal joint, and lumbosacral (LS) junction was performed in 1,018 Labrador retrievers in search for humeral head, femoral condyle, and tarsal osteochondroses; elbow and hip dysplasias; and transitional LS vertebrae. The ages of all dogs reported were one year or older. Elbow dysplasia was detected as the most common lesion (17.8%), with a higher prevalence in the male dog. Hip dysplasia was the second most common lesion (12.6%) and was found equally in the male and female. Elbows and hips were often affected in the same dog (4.2%). Transitional vertebral segments were found more frequently in the female (4.2%) than in the male (1.0%), and the condition was thought to be inherited.
I can't copy and paste from the PDF file, but if you open it you can read the abstract at top or the article that follows. Over half the Labrador Retrievers in the study were found to have joint dysplasia.
Quantitative genetics of secondary hip joint osteoarthritis in a Labrador Retriever, Greyhound pedigree by HAYS Laurel ; ZHIWU ZHANG ; MATEESCU Raluca G. ; LUST George ; BURTON-WURSTER Nancy I. ; TODHUNTER Rory J.
ABSTRACT Objective-To evaluate the quantitative inheritance of secondary hip joint osteoarthritis in a canine pedigree. Animals-137 Labrador Retrievers, Greyhounds, and mixed-breed dogs. Procedures-Necropsy scores ranging from 0 to 4 were obtained for each hip joint. Seven unaffected Greyhounds with normal hip joint conformation were also used for genetic modeling, but were not euthanized. Sixty-six male and 71 female dogs were allocated to 2 groups (< 12 months of age and > 12 months of age). Statistical models were developed to establish the inheritance pattern of hip joint osteoarthritis that developed secondary to hip dysplasia. Results-62 dogs had evidence of osteoarthritis in a hip joint, and 75 had no evidence of osteoarthritis. After sex was adjusted for, the necropsy score was found to be inherited additively but without dominance. Each Labrador Retriever allele increased the necropsy score by 0.7 to 0.9 points, compared with the Greyhound allele, and male sex increased the necropsy score 0.74 over female sex. Approximately 10% of the variation in necropsy score was attributable to the litter of puppies' origin. Conclusions and Clinical Relevance-Because secondary hip joint osteoarthritis is inherited additively, selection pressure could be applied to reduce its incidence. Similar statistical models can be used in linkage and association mapping to detect the genes in the underlying quantitative trait loci that contribute to hip joint osteoarthritis.
IN: American journal of veterinary research ISSN 0002-9645 2007, vol. 68, no1, pp. 35-41
Puff [YF, AKC field line (from competing HT/FT breeder) 62 lbs, dob: 8-'01]
Bess [BF, AKC bench line (from competing show breeder) 55 lbs., 1967-1981] "Poor Bess, the Wonder Dog":
Don't have time to go through the journal articles listed, but I just want to remind everyone that congenital does NOT equal hereditary. Congenital simply means present at the time of birth. Many congenital defects are hereditary, but are not necessarily so.
Otis - the most trusting dog on Earth.