Dark grey spots in duck eggs

[amerz08]

Hi, I'm hoping someone can help me. I keep getting these dark grey spots in my eggs. Sometimes they are small and look almost black and sometimes they are larger with a greyish color. There are also specks on the outer shell. They dont look like normal meat spots to me and was wondering if anyone could tell me what they are/how to avoid them? My ducks are 10 months old and eat purina duck food. Thanks

 

[GermanKennhuhn]

I don’t raise ducks, but it looks similar to meat spots in my chicken eggs. @Kiki

 

[Anime2lover]

Hi, I'm hoping someone can help me. I keep getting these dark grey spots in my eggs. Sometimes they are small and look almost black and sometimes they are larger with a greyish color. There are also specks on the outer shell. They dont look like normal meat spots to me and was wondering if anyone could tell me what they are/how to avoid them? My ducks are 10 months old and eat purina duck food. Thanks

I've seen them before. Their gross, but harmless meat spots)