Incredibly helpful book!This book is an excellent guideline to feed by breed!All breeds have different nutritional requirements based on body type, occupation, and origin. This book shows what types of grains, meats and vegetation are best for each breed in addition to going over general nutritional information re: vitamins & minerals, protiens, carbohydrates, fatty acids, how & when to supplement, etc.As an animal behaviorist and canine/feline clinical nutritionist I found this book to be an excellent tool and valuable part of my canine library.