Dogs are greedy and don't know when to stop eating .... so give them plenty.
I often think of this when weighing out the dried pellets my dog has for her tea. 40g twice a day. This blog post's title was written by one of the ten-year olds in the class I work with (actually, he's the class rascal). They had to write a report about dogs for someone who doesn't know what a dog is. Just shows the way their minds work. Such generous souls.