If you've never looked for these ratios, you'll find them listed on the side of the dog food bag. Beyond that, Stewart recommends keeping a close eye on your dog. "You should be able to see the lightest definition of the back rib and some nice muscle movement around the neck area when the dog is walking." Stewart conducts visual exams of his dogs weekly and weighs them once a month. (Click here for a body condition chart.) All of this information is listed on each kennel. In addition, Stewart will cut back a bit on his dogs' food in the summer when they're on light duty and go up a bit in the winter when the extra warmth from fat is beneficial.