Turkey sick-don't know what's wrong.

[nugget_night]

My six month old blue slate turkey seems to be sick. She has difficult standining up. She's not eating or drinking much, has lost weight, she cowers/ is off-balance, has lack of energy and is lurching now. We had to force feed and force water her. The chickens have been picking on her and she has no outward injuries.
We wish to treat her ourselves. We would like to know what we can do to help her.