Curved neck after possible attack, not acting normal

My 1-year old Delaware was possibly attacked about 10 days ago. She was making quite a racket and when I looked outside, she was flapping her wings wildly and then fell to the ground like she was dying. We live in a residential area so the only daytime predators are cats and and maybe occasional hawk. There have also been some bold Blue Jays hanging around. I went out and held her and she seemed ok and about 30 minutes later, she was running around with our five other girls. Three days later, I noticed she wasn't acting normal. She isolated herself from the rest of the flock, usually hiding in the corner of the coop or under our bushes. She is still eating and drinking, but not a lot. She moves slowly and methodically. I have checked her for impacted/sour crop and egg binding. I haven't seen any abnormal stools. I do notice that her comb is flopped over and her neck is curved. Could this be from the attack or possible disease? I am new to raising chickens, so any advice would be appreciated.

She sounds like she has wry neck, which can be a symptom of many different things, such as an injury, Mareks disease, and anything that can cause brain inflammation. Give her vitamins in her water that contain vitamin E, vitamin B1 (thiamine,) and selenium. Selenium can be found in eggs, tuna, salmon, nuts, and sunflower seeds. Make sure she is getting plenty to eat and drink.

Thank you so much for the great advice Eggcessive! At the feed store I was told to isolate her, give her antibiotics in her water and crumbles rather than pellets. I have vitamins/probiotics in the water. Should I give her something different? Would it hurt to give her antibiotics too?

Antibiotics won't do much good if there is no type of infection. Some many things can cause wry neck or torticolis, and some people never know the real cause. Is her crop large or is it just looking that way because her neck is twisted? Check it in the morning to see if it is emptying overnight. Was she vaccinated for Mareks disease, and have you ever had a bird die from an unexplained reason?

Eggcessive said:

Antibiotics won't do much good if there is no type of infection. Some many things can cause wry neck or torticolis,  and some people never know the real cause. Is her crop large or is it just looking that way because her neck is twisted? Check it in the morning to see if it is emptying overnight. Was she vaccinated for Mareks disease, and have you ever had a bird die from an unexplained reason?

Click to expand...

Her crop has been empty in the morning. That is her neck bone.
She was not vaccinated for Mareks. I am new to raising chickens, so I'm not sure what that is. All my other chickens are healthy.