One of my ducks has what feels like an edge of a tiny bone poking agains skin,other leg does not match and feels normal has a limp can still move leg and walk.. the other duck has a swollen hock and leg goes behind her when laying down really affects her walking slays down more than she walk and both can still swim.. both had a niacinDeficientcy when I get them. Saved with Brewers yeast. Dunno why this keeps happening two ducks down in a months time.. also is it better for ducks to be in water or can they stay on land.