Rooster attacked hen - treatment advice?

Y'all probably get these questions a lot and I've even treated injured hens before but my neurological disability is acting up and I seriously just can't remember any of the stuff that's chicken specific....

My rooster apparently finally overpowered the boss hen who used to boss him, and he's taken it too far. Big chunk ripped off the back of her neck. Do I wrap this? Just flush with water and apply ointment? I don't know exactly how long ago she was attacked, but it had to have been just a few hours ago at the most.

I can call the vet when they open tomorrow but they're closed now so I'm looking at least for initial treatment...

This same hen has survived being mauled by a dog, so she's tough. I still have some of her antibiotics and sulfadiazine cream from then so maybe just apply that? My head is so fuzzy right now, my poor girl. Lordy is a jackass