My Muscovy hen hatched out nine duckling.. That evening three got out from under momma and were close to death.. I put the three in my incubator and they warmed up and were thriving. That was Sunday morning. I had put two eggs that had not hatched yet in the bator and Monday morning they had hatched BUT the three ducklings were each dead... What could have caused this. Sunday night was suppose to be colder so I had kept them in the bator planning to return them back to mom this morning ... I have a cabinet incubator...