I fed it to Blue until he was 6 months. I prefer it because of the lower fat content. Reason being, this breed is predisposed to many hip and joint issues. I don't want him growing too fast as there's research that shows it may play a role in his dysplasia.
Here's some info. from Daniel C. Richardson, DVM Diplomate, American College of Veterinary Surgeons when he spoke at MSU years ago.
CANINE HIP DYSPLASIA
Canine hip dysplasia (CHD) is the most frequently encountered orthopedic disease in veterinary medicine practice. This extremely common heritable disorder of the growing dog can be influenced by nutrition. The period from 3 to 8 months of age appears to be important in the development of CHD, with the first 6 months generally thought to be the most critical. Early developmental findings of CHD, including joint laxity and coxofemoral anatomic changes, have been documented within 2 weeks of birth. Rapid weight gain in German shepherds during the first 60 days after birth has been associated with CHD at a later age. Frequency and severity of CHD are influenced by weight gain in growing dogs, especially if sired by parents with CHD or with a high incidence of CHD in their offspring. Dogs with weight gains exceeding breed standards have a higher frequency of CHD as well as more severe CHD than dogs with weight gain below the standard curve.(8)In one colony of fast growing Labrador retrievers, the triradiate growth plates of the acetabula fused at 5 months as determined by conventional radiography; normal closure of these growth plates in pups growing at conventional rates has been reported to occur at 6 months. Early fusion in the acetabulum is speculated to result in bone/cartilage disparities in the future and to predispose to dysplastic changes.(9) Limiting food intake in growing Labrador retriever puppies has been associated with less subluxation of the femoral head and fewer signs of hip dysplasia.
Overnutrition intended to maximize growth rate is incompatible with optimal skeletal development in many species. An early study suggesting a role of overnutrition in the development of skeletal disease in dogs was that of Hedhammer and colleagues in 1974(1); in an effort to study the influence of food consumption on the incidence of skeletal disease, these researchers performed an experiment comparing ad libitum versus restricted dietary intake in Great Dane puppies. The resultant skeletal pathology was markedly increased in the ad libitum group. This study heightened the awareness of the critical role nutrition plays in bone development.NUTRIENTS AND SKELETAL DISEASE
Energy (calories) is needed for normal development; however, needs vary based on breed, age, neuter status, and activity level. Energy is essential for growth (osteoid formation) and remodeling (resorption) of bone. A variety of methods are advocated to determine energy requirements, and, consequently, estimates of correct energy intake vary.(18) In general, growth requires twice the energy needs of maintenance. As the dog approaches adult body weight, energy needs decrease and are arbitrarily reduced to 1.6 times maintenance energy requirements when the dog reaches 40% of adult body weight.Rapid velocity of growth in large and giant breeds increases their risk of skeletal disease.(7,13) Excess energy per se in an otherwise balanced diet is not a direct contributor to skeletal disease in the growing dog(8,19); the link appears to occur when energy contributes to rapid growth rates and excessive body weight.
Differences in energy requirements may exist within breeds as well as among individuals. Newfoundlands and huskies may require less energy for growth whereas Great Danes have a greater than average growth energy requirement.(20) Although energy calculation estimates still provide an excellent reference point, they must be modified according to nutritional condition and level of physical activity.
No statistically significant effect has been seen on the incidence of CHD when a primarily carbohydrate energy source was included or excluded from an otherwise nutritionally adequate diet. Hip joint laxity, thought to be a predictor of CHD, does not seem to be influenced directly by dietary energy. Increased growth rate on a high-calorie diet stresses the tight hip and creates the potential for increased laxity around the joint and subsequent changes consistent with hip dysplasia. Similarly, an incongruent hip in a rapidly growing, overweight puppy may not mature with the musculature. Other than reduction of overall food consumption by restricting intake, dietary energy has minimal or no influence on the production or prevention.
Sorry for how long this is, just wanted you to understand why I believe the large breed puppy formula is better.