LOL I didbnt mean the actuall wing feathers. I meant the irridescent ones and the ones on Bandit that look like a strange mallard markings. Half the feather is irridescent and the other half is that cheetah print.
The iridescence is simply how the light reflects off the feather, the beetle green and purple are common in black and chocolate birds. The blue is found in the wing speculum on some mallard derivs.
As for the Muscovy, the barring along the breast is simply the first set of feathers ducklings with the wild-type gene get. It will begin to molt out soon and the new growth will be a solid black feather like what are on the back/wing.