About 2 weeks ago, I was given some Black Copper Maran chicks from a friend who had hatched them. Right now they are between 3-4 weeks old. I noticed right away the chicks didn't have the best down/feathers in the world, they were a might overcrowded where they had been, in a typical brood cage affair. I transferred them to a large old water tank that I use to brood. I've kept them clean, fed them medicated starter, given some VetRx in the water, all the things I've always done. Still, these chicks are not feathering very nicely. Their backs look like a chicken in molt, or a hen that's been under the rooster too much. I'd take a pic, but I think you probably know the look. No other symptoms. Mostly right between the wings, maybe a bit on the neck. They have NOT been vaccinated. I've tried that a few times, but am just not very good at it. They are separate from the rest of my chickens. If there were not Marans, I'd probably just cull them for safety, but this is my favorite breed. This guy actually raised his flock from some I gave him 2 years ago. Ideas, suggestions?