Help! My Chicken Got Attacked!

Chickens are prey animals and thus are subject to the threat of attack from many animals. The most common predator that a barnyard chicken faces is the dog. I have personally had encounters with this situation twice in the past year. Both times the dog's teeth cut into their sin and through their meat. It often looks bad but I do want to tell you that chickens are extremely resilient. In both cases I was both surprised and delighted with their speedy recovery and the fact that seemed mostly unfazed by the attack.
If your chicken has been attacked, the first step is to wash their wounds and flush them with carbon dioxide to prevent infection from setting in. If the wound is severe or you do not catch it quickly, consider administering antibiotics if they are available to you.
It is a good idea to separate them for a few days while they heal. If you keep them with the rest of the flock, the other chickens might peck at their wounds and cause an infection. You can use a temporary fence or old mineral tub. We use an old galvanized water tank. Make sure to provide them with plenty of food and water.
You may want to spray the wounds once or twice daily with antibacterial spray. I personally use Vetricin plus.
When the wound has healed you can return them to their friends. Watch them for several days to make sure the wounds don't reopen and the other chickens aren't bullying them.