I've had a terrible time with eggs going rotten in the nest when I let the geese keep their eggs. I bought some eggs from another breeder and decided to wash and disinfect them prior to setting. Out of nine eggs, I have eight fertile eggs. After I checked a nest and discovered the prior three fertile eggs gone and the rest rotten, I decide to wash and disinfect any more collected. I raided two more nests and have them in the incubator. It's early days, so I don't know the results yet. (I set them on the 11th of May)