ummm well set some camera's out so that you can catch the hen, and separate her..... and take the Wyandotte out of there before she gets killed by a blood frenzy
yes my dog would be like that too, although we gave her away. she was always a very motherly character. even when i caught a baby bunny she was like its mom. althought she would catch the pests and kill them and or eat them...:D