my chickens are losing feathers. It started with two of the GSL's they were starting to look like their back feathers were getting shredded, they were down to just the shaft after a few weeks and now both are almost completely bald in those spots, and on their necks in the front now. Then I noticed a few RIR's having the same issue with shredded feathers on their backs but they aren't bald there yet, but on their necks in front like the others is bald. My BR's have missing fluff on their bottoms too. And now my newbies, Amerucana's, two of the four are showing signs of the back shredding. I keep a VERY clean coop, I do a complete strip down, wash nest boxes and re shave the whole thing once a month, I do poop scoops in between. I keep the yard raked, and their water fresh. They eat 20% crumbles and I also offer scratch grains and mealworms (the dried kind in the container at the feed store, "Happy Hen" treats) and just recently sunflower seeds each day as well, I give them yogurt on occasion also that has crushed egg shells mixed in it. I am fairly certain it is a VERY dominant RIR I have dubbed Big Momma, but why so many of my girls are being treated this way I don't know? OR maybe it is a S _ _ t flows downhill kinda problem??? Big Momma picks on one, then that one picks on some one else and on down the line???? Any other suggestions? AND how do I get their feathers to grow back before the snow flies? Will they get too cold?