According to Dr. Tony Buffington, Professor of Clinical Nutrition, Ohio State University College of Veterinary Medicine, your puppy can be fed a regimen of specific caloric intake compared to his body condition score (BCS), using a simple one to five scale, from overly thin to obese. Using manufacturer feeding recommendations as an initial starting point, feed your puppy to a score of two and maintain this weight until he's fully grown. Feed whatever amount is necessary to maintain a BCS of two during the growth period, realizing that dogs have varying growth rates and activity levels. Once his adult stature is achieved, you may allow him to reach a score of three.
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2 = Thin - Ribs easily palpated and may be visible with no palpable fat. Tops of lumbar vertebrae visible. Pelvic bones less prominent. Obvious waist and abdominal tuck.
3 = Moderate - Ribs palpable without excess fat covering. Abdomen tucked up when viewed from side.