Several orthopedic diseases of dogs can be precipitated by improper feeding practices during growth. Large breeds of dogs are predisposed to these problems because they have the genetic potential for excessively rapid growth. In rapidly growing, large breed puppies, maximal growth, and therefore increased body weight, can cause stress on the immature developing skeleton. Large breed dogs have decreased bone density compared to smaller breed dogs at this stage (Dammrich, 1991). Additionally, fast bone growth results in structural defects of bones that are in turn unable to accommodate an increased body weight.
...There is currently no perfect formula to guarantee an optimal rate of growth for an individual puppy. It is especially important to avoid overnutrition during periods of the most rapid growth, which will vary with breed and between individuals. Breed and individual differences, environmental factors such as climate, and activity level will all affect the amount of food required. Obviously, palpable body fat is not specific enough to be a guideline for optimal nutrition. Provide an amount of food that will maintain lean body condition throughout growth. This will allow for a slow growth rate, but won’t affect the final adult size. The goal is to keep growing puppies lean at about a body condition score of around 4 on a scale of 1-9 (a score of 1 is emaciated and 9 is grossly obese). You should be able to easily feel the ribs.
...In addition to excessive energy intake, inappropriate amounts of calcium have also been shown to cause developmental bone disease (Hazewinkel, 1989). Many breeders and dog fanciers advocate calcium supplementation for growing pups. Calcium supplements should never be recommended for dogs eating commercially available diets designed for growth. Excess calcium is potentially very detrimental to the development of a healthy skeleton. Unlike adult animals, puppies appear to have inefficient mechanisms for regulating how much dietary calcium they absorb from the food. This can result in absorption and retention of more calcium, especially when the dietary calcium is high (Hazewinkel et. al., 1991, Tryfonidou, 2002). The excessive calcium may result in skeletal malformation (Hazewinkel et. al. 1985). Excess calcium can also cause deficiencies in other nutrients, especially zinc (Wedekind, et. al. 1998). Feeding a diet with too little calcium is equally problematic. Many home prepared diets for pets are lacking in calcium. In this case, the skeletal system must provide the calcium for the rest of the body, and brittle, malformed bones are the result. Current recommendations for feeding any healthy dog include choosing a nutritionally complete and balanced dog food that has undergone feeding tests. The guidelines for these tests are established by the Association of American Feed Control Officials (AAFCO). When such a diet is fed, vitamin and mineral supplements are unnecessary and potentially harmful.
The common practice of feeding commercially available adult dog foods to puppies can also be detrimental. The broad category of adult canine maintenance foods contains diets with a wide range of nutrient profiles, caloric densities, and mineral contents. Some foods marketed for adult maintenance have passed AAFCO feeding tests for growth, but some have not. Regardless, in some instances, these diets provide more calcium per calorie and/or have more calories per cup than growth diets designed for large breed puppies. A large breed growth diet that has passed AAFCO animal feeding tests should be fed at least until the puppy reaches about 80% of the expected adult weight, and it will not be detrimental to keep a healthy, lean puppy on growth formula until full adult size is achieved. Above all, remember to feed a large breed growth formula in sufficient quantities to maintain a lean body condition, and avoid additional supplements.[/b]