One of the many reasons I picked Broken Toe as my Rooster, his beard and muffs, were a nice dark blue right off the bat and very full.
Sadly, one or more the the girls has been grooming him and pulling out some of his beard.
Have another rooster, a very nice d'Uccle who has an incredible beard and muffs... but the last batch of girls made him bald. He is now in a pen by himself and he is slowly growing everything back in.
If you are going to show, the only way I can see to have them keep their muffs and beard, is to keep them in their own pens.
Using my d'Uccles as an example.... they are born with muffs and beards, and will grow in quickly. Some of them have hatched with such full muffs, the baby feathers were in their eyes and a bit of a problem. One has to watch for that.
Now my d'Anvers, chicks do have a nice beards and muffs, but when their first feathers come in, their M&B's take a little longer to come in.
Since I have only raised one Gen of AM's... with my Blue Wheatens, they hatched out with full muffs and beards. When their first feathers came in, it took a month or so for their M&B's to come back in.