We follow the 'three-rib' rule for our greyhounds - you should always see the last three ribs - and modify their food intake by 1/8 to 1/4 cup if they are showing too little or too much rib! Buddy is about 75 pounds, and he has a slow metabolism and is lazy He gets 4 cups a day, but recently he started eating only about half of his breakfast. We tried giving him 1 cup of his food and one cup of Pup's weight control each meal, and now he is back to eating 4 cups. Paula is about 54 pounds, and frail, and she gets about 3 3/4 to 4 cups per day. Boo is our high energy, spastic, high metabolism girl, who could probably eat 6 cups a day and not gain an ounce. But we keep her at about 4 1/2 to 5 cups. All the greyhounds get Nutro Natural Choice Lamb and Rice, and some playtime in the yard (and neighborhood walks).
Maybe greyhounds have naturally higher metabolisms than other dogs?