How old is he?
Do be careful, if the babies are young as drakes can do a lot of harm to ducklings and should be separate.
Dawn baths are sometimes used for severe cases of wet feather, or for birds that are involved in oil spills, as it will strip the oils from their feathers- however it...
What is the feed? And how much does he get, is he eating okay and showing a good appetite? Be careful not to overdo the veggies and fruits as these can water down the nutrients they're getting from their feed, it's okay as a treat, but treats ought to only make up about 10% of their diet. The...
What does their diet consist of? What amount of fresh veggies/fruits and what amount of feed, what type of feed?
Does he live with other drakes? They could be bullying him