Dark Spots in Eggs

[ecse129]

I tried posting this in ducks, but there isn't nearly as much traffic in that forum as here. I candled my indian runner duck eggs at around 21 days and found that they were developing nicely. However, a few of them have these small dark spots inside the egg. They are not visible on the outside, just when candling. They are still moving inside so I know they are still alive, but am worried about their health. Are these bacteria spots or normal? I haven't seen them before in previous batches.

 

[chasinglights27]

Interesting!!! I dont have an answer, but would like to know too. I have 16 Runner eggs in the incubator. Hopefully yours hatch out fine.