Dry scabby skin on my rooster

[Chewie]

My rooster has really scabby skin that looks like yellow dry skin. He is pulling his feathers out on his back and upper part of his tail. Please help me figure this one out.

 

[chickenzoo]

Have you checked him real good for lice or mites, they could be aggravating his skin? Also feeding some flax seed or something to help his skin.

 

[Chewie]

Yes I've checked him for lice and mites. I've dealt with the Northern Fowl Mite before and he doesn't look anything like that. I don't really know what mites would look like though because my chickens haven't had them. Would post a pic but I already sprayed him with Blue Kote just in case he had some type of fungus on his skin. I'll try giving him flax and see if that helps. Thanks for the ideas.