While there is not 100% agreement among Lab breeders or all vets, as far as I know there IS 100% agreement among canine nutritional scientists that large breed dogs (such as Labs) should be fed a formula especially formulated for LB puppies up to 12 months or when adult height is gained.
Below is a copy of a post I've frequently made:
Labs are among the "larger breeds" that have a lot of joint problems -- about one of every 3 dogs among Labs.
Joint problems are caused primarily by 3 mutually interacting factors:
-- stress, injury, such as caused by jumping, leaping especially before adulthood
-- genetics such as caused by breeders not having their breeding dogs certified for hips & joints AND not checking for that in the pedigree line -- in short, puppy mills, backyard breeders, scam breeders
-- diet such as caused by feeding a large breed puppy a food that is not specially formulated for large breed puppies; a LBP food controls the amount of calcium delivered
Once you have your Lab, you CAN fairly much control the activities that could cause stress or injury AND you can absolutely control the diet your Lab gets. Doing both of those lessens the probability that your Lab will develop joint problems.
Below are a few references on the importance of feeding a Large Breed Puppy food for the first year. (There are NO scientific articles claiming the opposite.) The references are from a post I've made so often that I just recopy it.
My very strong preference -- for all Lab puppies under a year old -- is to feed a Large Breed (formulation) Puppy Food, such as made by Diamond, Eukanuba, Nutro Natural Choice, ProPlan, or Science Diet, etc., for the reasons given in the articles below:
Within it, it contains this statement and references:
"The scientific literature is very clear on nutritional changes to "help manage" the potential orthopedic problems in growing large and giant breed dogs. Here are a few citations for you. As you can see from the dates on these citations, it is “old” news to vets but pet owners and breeders are still making dangerous recommendations."
1. Nap, et al. Growth and skeletal development in Great Dane pups fed different levels of protein intake. J Nutr 1991; 121:S107-S113.
2. Hedhammer, et al. Over nutrition and skeletal disease: an experimental study in growing Great Dane dogs. Cornell Vet 1974; 64:1-159.
3. Lavelle. The effect of overfeeding of a balanced complete commercial diet to a group of growing Great Danes. In: Nutrition of the dog and cat. Burger and Rivers (eds). Cambridge Univ Press, 1989:303-316.
4. Hazewinkel, et al. Influences of chronic calcium excess on the skeletal development of growing Great Danes, J Am Anim Hosp Assoc 1985; 21:377-391.
5. Goedegebuure, Hazewinkel. Morphological findings in young dogs chronically fed a diet containing excess calcium. Vet Pathol 1986; 23:594-605.
6. Hazewinkel, et al. Calcium metabolism in Great Dane dogs fed diets with various calcium and phosphorus levels. J Nutr 1991; 121:S99-S106.
Puff [YF, AKC field line (from competing HT/FT breeder) 62 lbs, dob: 8-'01]