Walmart or just about any pharmacy, ask for plain niacin not time released or flush free 250 mgs and give him 2 to start with mixed into 1 gallon of water. Duckling can have a Niacin deficiency which can cause leg problems and maybe it would be worth a try to see if it would help. I'd put him in water at least 1X a day even if he just stands, you never know when he may just start using the leg especially once you start the niacin. Put him in the deep part and let him get to the shallows by himself, but stay with him while he's in and make sure he can get in and out safely.He has gone swimming a couple times but,he does not seem to enjoy it as much as he used too... but i think he uses it when he swims.I noticed he likes to stand in the shallow parts and just stand on one leg.I have not given him any niacin.,where can I get some?