Black marks in duck eggs

[xx_li_xx]

Hello everyone

I am incubating duck eggs, we have 8 that are due to go into lock down on Wednesday, however yesterday I noticed one of them had a black mark inside and then tonight have found another with one. All are moving well , 2 look like they are trying to internally pip , but I am so worried about these black marks.

Any ideas anyone ?

I’ve been such a worry with these as they were shipped eggs and lots of messed up air cells all at the moment though are moving and wriggling.

 

[Amc29]

I am not 100% sur re, but I believe I have seen something similar in a post about chicken eggs and it ended up being little clots. I believe the chick(s) hatched okay, though. Perhaps this is something similar. Hopefully someonebwho is more experienced/knowledgable sees this and can give you some answers.

 

[Chickinie]

Maybe it's the babies waste, they might be going to pip at the wrong end..