I have two Polish chickens that are I think around 2 - 3 years old. One silver laced Polish hen, and one buff laced Polish cock. I've noticed that on the very top of my rooster's crest, it usually appears kind of flat and the feathers are a little broken or they are just stubs where the feathers should be (but he is not picked on). On my hen's crest, depending on her mood, it usually appears kind of narrow and not fluffing or fanning out like I've seen other Polish hens' do. Neither of them are molting at the moment, but always some of their feathers on their crest appear like they are molting or growing new ones constantly. I occasionally give them fully submerged water baths with gentle dog shampoo, rinse them off and then towel dry them a little before they dry themselves, and I've noticed that makes their crests and feathers look a little better a day or so later. What can I do to improve their crest and overall feather quality? Should I change their diet (they both eat regular layers crumble food and whatever they can find outside plus some scraps occasionally)?