ok so this happened to my chicken and not a duck but maybe you will have the same results. One of my 3 day old chicks got out of the brooder and apparently my dog decided to "save" it. When I found the poor thing I thought it was dead for sure. It was laying on the floor totally wet, not moving at all, cold, and I thought was surely soon dead. I felt sorry for it cause it was still breathing but as I said soon dead. I put it under the heat lamp thinking that even though it is soon dead, at least it will be warm and not cold....soon dead. I came back a while later and checked on it and it was still breathing..not moving..soon dead. I cut out a small box with holes in it and put over the chick...darkness might calm it down...later I picked up the box and the chickie was sitting up but still not moving...I put the box back over it...came and back later and the chickie was sitting up. I took the box off so that it had access to it's water and food. It didn't eat right away but later it did. Three days later you would never know the poor dear was on it's death bed. You might try it. I worked for me.