I've had many dog attacks in my years as a chicken owner and in my case, if they can survive the attack, I've healed them with this method. There is a purple iodine type liquid at Tractor Supply; might be "peck no more." Coat the entire wound with this. Reapply daily as needed for any part of...
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Hot here in Texas! Our chickens need plenty of accessible water!
I've used iodine on large hen wounds. The blue color keeps other hens from pecking and the iodine dries into a cast-like cover.
You can get a predator red light and attach to the outside of the coop. It blinks like eyes at night.