Candling question. . .please ease my mind!

[cici_p]

Candled my duck eggs on day 7 and all but two have obvious development and veining!!

However, several of them only have veining on one side of the egg--so say on the "front" of the egg, they have beautiful development, a clear embryo, dark, compressed looking yolk, etc. . .but as I turn to the back there is. . .nothing. Just complete blank. . .until as I turn it starts again on the front side.
Is this at all normal?
Or is something wrong here?
I have my eggs in cartons (with the bottoms completely cut out) because so many had loose air cells. . .now I am worried if somehow the cartons could be cutting off the air supply, thus altering the development on one side? Or maybe this is just completely normal and I didn't notice it with my last egg??
Thanks for any help!

 

[mirecipes]

I know nothing about duck eggs, and it's late here so I'm tired

Are you turning these eggs?
From what I understand, you need to turn eggs to "exercise the embryo"

 

[cici_p]

Yes, turning the same way eggs are turned in a turner, by tipping the carton on one side then the other. Seems like a pretty significant tilt, but maybe it isn't enough?

 

[dancingbear]

It's enough. I've seen egg appear to develop off balance, then turn out just fine. I read your threads about the loose air cells, if these are like that too, you don't want to rattle them around too much. The embryo will be exercised fine with tilting, and won't stick to the shell.

Think of the way an embryo's body curls in the egg, sort of like the letter "C". There could be clear space on the front, where the gap is.

 

[cici_p]

So what I'm seeing is normal?
Schwew!

 

[dancingbear]

Without seeing yours myself, I can't swear they're normal, but I've had some that fit the description, and they were fine.
Sometimes it's hard to tell, you just have to wait and see. The dark areas should grow larger until they fill all but the air cell.