HELP! Quail has a naked back?

Probably being pecked by the other quail.

 

Well, you can cull the bully, separate them, coat the quail's back in no pick lotion etc.

 

Either the bird is being over bred or someone is pulling it's feathers. What is the ratio of roosters to hens in that cage?

 

Then either the rooster or one hen is picking on that bird. Hens are the source of aggression just as often as roosters are.

 

All my hens look like this. Is this not normal for roos to do?

 

No it's not "normal" per se. It is normal to have a few feathers get pulled from the back of the head but not to bald the bird. That is a sign of too few females or bullies usually.

 

It's normal if you have too many roosters or not enough hens. If you're playing your cards right all your birds should look healthy.