I have a muscovy duck that has barely any (if any) oil on his feathers. He takes a bath every couple of day and then preens himself for at least one hour. When he takes a bath he gets completly soaked down the skin, feathers and down are drenched just from being in the pool less than a minute. Its takes him about 3 hours to be completly dry. Because it is starting to get down below freezing at night, I am worried that if it rains and he gets wet then he will freeze to death. What can I do to help him? Is there anything I can add to his diet that will help?