yes. They are bugs and chickens will eat them for sure. I have never "fed" them to my chickens, as we find them on us that is, but I am
positive they eat them. Idk if they are bad for them, but the number of ticks we had here have diminished greatly since I got my chickens and let them free range. I wouldn't think they would hurt chickens though.
I have had my chickens over 2years now and have never found a tick on any of them. Not to say that it's impossible, but I have never seen it. I do have a lot of chickens, but we hold them on a daily basis