I have a small family goTs chickens ra bits. One day a black muscovy and white duck came into our yard they hang out with the chickens swim in a pool we have there and don't leave. So there part of the family. Picking up eggs on day I noticed eggs on the floor of the goat den in the corner...
They free range we give them layers and fruit. They get into the goat food that has molasses and corn that could be the problem. But they get a lot of exercise there is 1.5 acres.