Hello there and welcome to BYC!
Oh I am so sorry about your Barred Rock!
Make sure her wounds do not infect. Even if they are minor, they could cause trouble. You can use neosporin (without the pain killer) or some other antibiotic lotion on her wounds. If they are deep, I would get her on antibiotics just in case...something like PenG injections or if you don't know how to give injections, you can give her Amoxicillin orally.
Do you have her on chicken feed yet? For now you can feed her cooked, warmed and chopped hard boiled eggs. All the building blocks of life in an egg and is great emergency food for sick birds. She will need a Layer feed of some sort when you do purchase her food. You can feed her a bit of greens, veggies or cabbage and such. Here is a treats chart you can find other things she may like to eat...
https://www.backyardchickens.com/a/chicken-treat-chart-the-best-treats-for-backyard-chickens
They can go into shock easily after injury, so keep her in a quiet room with without bright lights. You might put a ticking clock in the room with her. Birds really find the ticking soothing. Don't handle her much until she feels better. Keep up with good supportive care.
You might stop by our learning center for lots of great reading on all the aspects of caring for your new bird...
https://www.backyardchickens.com/atype/1/Learning_Center
And if you do find she is taking a turn for the worse, please do post in our emergency section for more help with her...
https://www.backyardchickens.com/f/10/emergencies-diseases-injuries-and-cures
Well, I hope she pulls through!! Keep us posted!!
And welcome to our flock!
