I was basing what I feed Jimmy on several different articles based on 55 pound dogs (he's 60, so I figured it'd be similar). But as each dog is different, it's really a matter of experiment. Jimmy was starting to look a little slimmer (he's probably about 5 pounds overweight, but as Aussies tend to gain weight easily, I want to keep that under control), but after the past two days, he's been bulking up again. I cut about 1/4 cup of what I feed him to see if that does anything. If not, then I'll cut a little more. But I don't want to starve the poor guy either, so I'll do it slowly.