My EE chicks are now about 8 weeks old or so and they have been doing well, I got them from MPC. I was just going to bring them outside to the coop. when I came to feed them last night one had her head bent down in front of her like under her chest area. I picked her up and her neck started like turning, i set her down and she like put it down again. I dipped her beak in some yogurt and she ate some I thinkI have never seen anything like this before. They were vac for Mareks. Please help me what do I do, she is with 5 others that aren't doing this. Today she is like just holding it down a little but she doesn't have it down like last night and she is like walking around ok. I have them on med starter and corncob bedding. She seems alright but what would cause this, thoughts please!! Thanks very much!