One of my female ducklings (a little over 1 month) is limping today. She has no noticeable injuries. No scratch. No infection. I don't believe it is niacin defincency because all my ducks are outside full time now where they have access to grass, bugs and an endless supply of worms from the compost pile (which I have seen them pulling worms out of). I attached some pictures so if anyone has an idea of what it might be please feel free to share.