I have a young swan who became sick over a weekend, It was guessed that she had bottulisum. she was drooping her head walking backwards and not eating, or unable to eat.

I took her to the vet and she could find nothing wrong with her bodily functions, heart, breathing eyes etc. All seemed fine except for her neck and head position. She walks around with her neck curled up on her back and her head resting on her back. She is eating well now and originally received four 1cc shots of penicillin for four days in a row. I hate to see her with her head and neck like that, but my wife thinks she will probably stay that way.

When I pick her up and feel of her neck, it feels really tight at the bottom next to her body, like her muscle is contracted.

Do you have any experience with something like this? Also there is no sign of any injury , her neck feels fine, with the exception of a few small bumps along the neck, but nothing irregular feeling.