I have not been on this site for years, married at chickenstock 2006 in TX at Allen Wranch's..., I was miss amara - official henbassador... LOL. anywho I had this issue with some duck babies I had and found little help here or anywhere. Hope I can give a head's up. If your ducklings are young and show distress with foam in the mouth and nose they are choking. First off if you run out of feed and water always rewater first before feed. That doesn't always work so if you still end up with chokers feel the neck. If unsure how it should feel grab a happy duck and feel his neck. Should feel smooth. The difference between him and the choking duck should be obvious. On the choker push the lump up. It is a jacked up Heimlich Maneuver. You will see the lump of feed come into the mouth and use a tooth pick or something to scrape out of the mouth. He will be all happy... and alive.