What is supportive care for a goose?

We've had 2 geese for about 10 years. They live out by our pond and have free range of our property. About 2 months ago I made the mistake of keeping my dogs in the house overnight and one goose was attacked. She had a tear on her neck and we gave her corn, oatmeal and water close by and left her out to recover. She was doing well, but has stumbled sometimes while walking. Yesterday afternoon I noticed that she could not get up. This morning she is still alive, so my grandsons and I went out with a wagon and dog kennel to put her into a more safe situation. She has no injuries that are visible. Her legs and beak are a slightly different color than normal. I don't know much about geese. What can I do for her (or him). What would be the best food to put in there? I am hoping that maybe she'll be okay with supportive care. She is eating and drinking very well, just can't walk. I did notice that her eyelid is a little green and her poop is very light green and looser than normal.