
In my experience all dogs want more! I have one dog who'll choose to miss breakfast fairly often, but if he misses his supper, or if any of the others don't finish their food and look for more I know they're ill!
If you can feel, but not see, his ribs when you stroke his sides, then he's about right. Remember, the feeding guides are for 'the average' dog - who doesn't exist.
:)