I took on two, two week old ducklings 4 weeks ago after they had been injured by crows they were both doing reasonably well the little girl had a broken foot which has sorted itself out out on its own but recently I think something has happened to it she is pooing green instead of white not eating or drinking as she was & is not able to stand up up and she is now making a gasping sound and opening her mouth and isn't the duck that she was when I took her on and when she was rehabbing please can anybody give me some idea as to what happened :-(