When do eggs become fertile

[ProperPoultry]

Hi all , I recently bought a trio of Indian runner ducks (1 male 2 female) I got them yesterday from a local farm which had a lot of male and female ducks. This morning I walked into the coop to find two duck eggs. Which brings me to the question are theses eggs okay to incubate or not. Will they be fertile and maybe the father is another duck at the place where I bought them

 

[Amiga]

They are likely to be fertile, and you are right - no way to know which drake they came from.

 

[ProperPoultry]

Perfect thank you