Our hen Hettie started showing this behavior a couple of days ago. She'll look up, and turn her head repeatedly, as if she's having some sort of fit. It can go on for minutes or hours. It tends to happen almost entirely at night (I saw it only once, for a few seconds, during the day). Today she seemed fine during the day (though less energetic than she's been in the past), but at dusk just as she was walking into her coop, this started again, and hasn't let up since. The two nights before that it seemed to happen at the same time too, just as she's going into her coop at night. Maybe darkness triggers it? Or darkness triggers stress, and stress triggers it? I don't know what the problem is, though the symptoms may correspond to what is sometimes called wry neck or crook neck on this site and others, and which is variously attributed to vitamin B deficiency or head trauma. It's the fact that she goes in and out of it that most confuses me, though. We started putting vitamin powder in their water yesterday. A short video of the seizure-like behavior that started tonight as she attempted to enter her coop can be found here: 1) What type of bird, age and weight (does the chicken seem or feel lighter or thinner than the others.) Welsummer, 4 1/2 years old. She's a large bird, and still seems to be, though I think she's eating less since this started. 2) What is the behavior, exactly. Seizure-like behavior in which she looks straight up and repeatedly rotates her head from side to side. I've seen it clear up after a few minutes, but tonight it seemed to go on for hours. It started 3 days ago, and each time it struck worst right as she was going in her coop at dusk. I only saw it strike during the day once, for just a few seconds. Otherwise, during the day, she walks around and pecks, though less energetically than usual, often just standing and staring. During the day her head is kept a bit closer to her body than usual, but otherwise moves normally and can extend fully to peck and eat. 3) How long has the bird been exhibiting symptoms? Tonight is the 3rd night. 4) Are other birds exhibiting the same symptoms? No. 5) Is there any bleeding, injury, broken bones or other sign of trauma. I've seen a bit of blood on her comb, but I've also seen other hens and the rooster peck at her head since she's started doing this, so it could be from that. No obvious injuries otherwise. 6) What happened, if anything that you know of, that may have caused the situation. I don't know of anything. 7) What has the bird been eating and drinking, if at all. I've seen her peck and eat, both foraging and at seed I give her, and there is food in her crop, but I think she's eating less than she did before this started. 8) How does the poop look? Normal? Bloody? Runny? etc. I haven't specifically noticed her poop yet, but will keep an eye out. 9) What has been the treatment you have administered so far? Putting vitamin powder (which includes several B vitamins as well as others, and electrolytes) in the water that all the chickens drink from, at the recommended dosage. 10 ) What is your intent as far as treatment? For example, do you want to treat completely yourself, or do you need help in stabilizing the bird til you can get to a vet? If this can be diagnosed and treated myself, I would like to. If no improvement pretty soon I will contact a vet. 11) If you have a picture of the wound or condition, please post it. It may help. A short video of the seizure-like behavior can be found here: 12) Describe the housing/bedding in use Enclosed coop with attached run, wood shavings for bedding. Thank you all for any information you can share! Hettie's a good bird and I'd be very sorry to lose her.