I have two RES. One of them becam every aggressive and bit the other onthe neck, It was bad, he didn't want to let go. We've since separated the. The neck on the one that was bit is swollen, mostly where he was bitten, I don't think he can move his head much, or he doesn't want to b/c it's painful. Is it infected? What can I do?
Take the injured turtle out of water. Clean the area with diluted betadine or diluted chlorhexidine and apply some neosproin. And as soon as you can, get your turtle to a vet: