MORE INFORMATION: in one of the above article there was a lady who mentioned that the Muscovy drakes are prone to this. The cure? Pen them and put in something big enough to dip their heads in. Clean water important. I did it.
I just went out and checked, and one hour later, white foam things gone. I don't know if it is permanent, but there is something to this. I am only mentioning as in the future someone else will be searching here for the same thing and trying to lay down information.
FYI: Two weeks ago they all discovered my pond. Good sized, full of bugs, duck heaven. He is beside himself he is so happy down there. He still comes to the house several times a day for his treats, the ladies in tow. Then back to the pond and is sleeping on a little island in it. He is happy. I don't have a predator problem and very difficult for a swooping hawk or something. I would rather he was penned up and safe, but he is so gleefully happy I let him live the life he wants.
That said, I am wondering if the amount of time in the pond has something to do with it. In fact, most definitely. He doesn't care about the clean water kiddie pool up top anymore and who could blame him.
Which brings up another question. This can't be a unique situation. Muscovies live all over the place in ponds and such. Any suggestions going forward?
And if the foam thing returns in the morning to the vet. At this point I am thinking of canceling the appointment?