I have a 2 year old white giant hen that started keeping it's head down two weeks ago. Checked it's crop and it was hard. We massaged it for two/three days and now it is soft. We thought this was the reason for her weight loss. We gave our flock antibiotics for 5 days and she seemed to be better. She now is unstable on her legs and sits a lot. I noticed today that she has multiple knots in her upper joints of both legs and a little swelling between her toes. She continues to eat and drink but as I mentioned sits majority of the day. She will move quickly away from you if you try to pick her up.... so she has energy but not like the othe hens. Has anyone heard of deficiency that may cause her joint problems? The hens is fed layena pellets, crushed oyster shells and get grit. (We are located in North Carolina and the weather her has been mild 50's, 60's and low in the 30's. Except today COLD low 19 and high 40. Any ideas anyone? Her poop is normal and has no other signs.