Hi all, I have a pair of ducklings about 14 weeks old. One of the ducklings legs shake horribly while standing still. It seems the right leg is worse than the left... is there any ideas what this can be, is he just cold or nervous, or is he demonstrating some health problems. They are currently eating flock raiser, they get to swim in a large kiddie pool often. We just want to know if this is some health problem or nutrition deficiency how we can correct it. Thanks!