Hens missing feathers above tail

[Joshy Roo]

Hello, I just got a few pullets to add to my flock. The 3 Barred Rocks are in a bit of rough shape and are in a quarantine coop.
2 of the girls are missing rather large patches of feathers on the lower back right above the tail and it extends quite far on one down the sides so that the wings are covering it even. Ive been watching them and have seen the hens pick at their own baldness, with an occasional light peck from the others.
I understand they could be calcium deficient and eating their own feathers?? I have given them a good amount of Layer feed and extra oyster shells.
I am concerned about further pecking from the other birds also in the quarantine coop.
Is there a home remedy with blue food colouring I can make to apply on the bald patches to deter further pecking??
Any advice would be greatly appreciated. Below is a pic of one of the birds, her wings are covering up some of the area too. the other bird is 2x worse.

 

[M-H-Fielding]

The feather loss was most likely caused by a rooster when mating. Their feathers should grow back.

 

[M-H-Fielding]

Do you have them in with a roo?

 

[Bigtom Turkey]

You can buy hen saddles.

 

[ChickenCanoe]

They look like young pullets, not hens.
If no roosters in the flock, it is probably cannibalism.
If you can correct that, they'll regrow feathers in the fall with molt.

 

[Joshy Roo]

Do you have them in with a roo?

No I just got them from Hatchery yesterday and there is no roo with them. They are about 18 weeks old. Im not sure if a rooster would have done such extensive stripping on such a young bird that just hitting maturity. In comparison, what my rooster has done to his favourites looks more mangy just on top the back and shoulders vs waxed clean off and down the sides.

 

[TheAlrightyGina]

I am having a similar issue with established members of my flock--two BCM hens (or at least, they will be 1 yo in a couple of weeks). Everyone else in the flock is fine, no feather loss. There's no male in with them, so that rules that out. I've checked for mites, nothing. I've watched closely, no one seems to be pulling their feathers or bullying them. But the feathers right above their tail are missing or broken. Makes me wonder if it's some kind of genetic fault (since it's just the two BCMs and they came from the same place) or if there's something they're sensitive to that the others aren't. For the life of me I can't figure it out. Might try putting saddles on them to see if that clears it up.

 

[Duckbreeder2020]

You can buy hen saddles.

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