Darkness around air sac - duck eggs day 28

[Myavia]

Hello there!


I am on day 28 of incubating my ducks eggs. I have 7 eggs hatching in the next couple of days, due to a staggered hatch, but I had 2 eggs due today. Of the two, one hatched very very early this morning. The other one did not have a pip, and was not moving or peeping in response to me talking, like the other egg had been before it hatched. I took it out and candled it this morning, and saw that the duckling had internally pipped, and was moving around alive in there. It even responded to my tapping by tapping back.
Now, about 12 hours later, the egg is still in the incubator, but it has developed a dark line on the shell, outlining the air sac inside.
I left it for an hour or two, and the darkness seemed to grow, so I candled it again (after carefully inspecting for any pips). This time, I did not see a beak in the air sac, and I did not see any movement.
Does anybody know what could’ve happened?

 

[TwoCrows]

I moved your thread to our Ducks forums for more help. Let me tag a few members that might be able to help.

@Isaac 0
@Miss Lydia

 

[Isaac 0]

Just basing off your description, it's still hard to tell what exactly is going on. Could you open the incubator real quick, candle the egg, and take a photo of what you see?

 

[Trisseh]

Are you able to take a picture of it while candling in a darkened room? Sometimes it’s better to show as well as describe.
I had one that had internally pipped, shoved itself into the air cell end, and turned itself and was unable to externally pip. Sometimes they turn themselves the wrong way. If you want to investigate further, you can make a hole in the air cell end as you would for assisted hatching, and go from there. I’ve linked the guide below for your perusal if you want to go that route.

Guide to Assisted Hatching

but we’ll be able to help much more if we can see what’s going on

 

[Myavia]

I’m sorry, but I’ve been using my phone flashlight to candle the eggs, and I don’t have anything else to candle with or take a photo with.
I went ahead and made a small safety hole in the very top of the egg (air sac side).
Could the chick have become malpositioned when trying to pip?
i saw a very prominent break in the air sac earlier today, but now the air sac looks how it did a couple days ago (regular, unpipped air sac).

 

[Isaac 0]

I’m sorry, but I’ve been using my phone flashlight to candle the eggs, and I don’t have anything else to candle with or take a photo with.
I went ahead and made a small safety hole in the very top of the egg (air sac side).
Could the chick have become malpositioned when trying to pip?
i saw a very prominent break in the air sac earlier today, but now the air sac looks how it did a couple days ago (regular, unpipped air sac).

So just to clarify, you see no movement in the air sac, do you hear anything? Try checking the other end of the egg. Do you see any dark bruising? I think a safety hole was a good call.

 

[Myavia]

So just to clarify, you see no movement in the air sac, do you hear anything? Try checking the other end of the egg. Do you see any dark bruising? I think a safety hole was a good call.

I didn’t hear anything when I tried tapping on the egg, after the dark colouring appeared.
Is it safe to take the egg out and check? Or will it get shrink wrapped?

 

[Trisseh]

Is the dark colouring visible on the outside of the egg, without candling? As Isaac said, it’s possible your duckling is turned the wrong way in there and could be trying to pip on the wrong end of the egg.
it depends on how hands on you want to be. You could open the air cell end a little further so you can access the inside a bit, and use some coconut oil/olive oil/triple antibiotic ointment to moisten the membrane and see what end of the duck you can see and if there are veins still active.

 

[Myavia]

Yes, the dark colouring was decently visible from outside of the egg. I noticed it looking into the incubator.
So it wouldn’t shrink wrap the duck if I took the egg out to candle it again?
If I did expand the safety hole to look in, which part of the inside exactly would I be wetting with the oil?

 

[Trisseh]

When you look in there, there will be a space between your hole and the membrane, which is the air cell. The membrane usually looks white and opaque when you open the egg up. That membrane is what you want to carefully and gently moisten with your oil or ointment. I usually use a q-tip because they’re soft and easy to maneuver. If there’s an obvious hole in the membrane that you can see right away, avoid getting any oil near it in case the beak is hiding just around the corner.