We do it right away. The fear level is smaller that way. It is sad to see a bird dog that scared of a chick.
In his defense Maude one of our orpington is very intimidating. She is Godzilla stuck in a chicken body.
She is the first to assess and put whatever is in the yard in its proper place in the pecking order.
My Mastiff is terrified of the chicks. They peep! They peck! He hides.