Please help! This happened after dog attack!

[Pratik1234]

Hello my chicks got attacked 3 weeks ago, some of them Survived but few of them fluffed up and started loosing feathers on their back.

Its been 3 weeks and this chick still hasn’t recovered, it’s skin is dry and I don’t know what it is or how I can help the poor baby, ( there were no bite marks by the dog) so I’m very confused need help!
This are the recent pictures!

 

[micstrachan]

How do the others look? Did their feathers grow back? I wonder if her flock mates are plucking the feathers as they come in? It looks like she has been scratched.