Ask your vet to tell you how much he weighs in pounds and ounces. I had a BIG discussion with my vet about this. He had never had anyone question him about it..he's only been in practice a couple of years. So now when I go in, he just pushes the button on the scale to change it to ounces instead of tenths! He said he prescribes his meds by tenths, not ounces. I thought it was very interesting