Developing duck egg has air sac at wrong end

kiwichiks

In the Brooder
Dec 12, 2015
55
13
31
New Zealand
I recently purchased 4 fertile Magpie duck eggs for my teenage daughter, who has been DESPERATE to raise ducklings for a very long time. After much 'Googling' and researching, we built a home incubator and started incubating (we have never done anything like this before). We candled the eggs at Day 7 and again at Days 11 and 12 (after the temperature in the incubator became unstable).

At Day 13, we confirmed two very active embryos (and 2 yolkers) before transferring the developing eggs to my mother's hen, which fortuitously, had meantime become fervently broody!

My question is in regards to one of the two developing eggs - our 'special needs' egg. After candling on Day 7, we discovered that it had the air sac at the pointy end of the egg! The eggs were not shipped - I picked them up from a local supplier whose ducks live nearby. We weren't sure how we should place this egg in the incubator so just lay it on its side. We placed the other normal egg with the blunt (large) end slightly elevated. Both eggs were turned by hand 5 times a day.

We haven't candles the eggs since the hen took them on at Day 13, but if all has continued to go well, the ducklings will be due to hatch on the 27th of December (today is day 24).

I'm really nervous about our 'special needs' egg and wonder if it's safer to leave this egg under the hen for hatching, or whether we should take it back on Day 26 or so, to monitor it in the incubator, in case we need to assist it in hatching. Any advice would be very much appreciated!
 
I recently purchased 4 fertile Magpie duck eggs for my teenage daughter, who has been DESPERATE to raise ducklings for a very long time. After much 'Googling' and researching, we built a home incubator and started incubating (we have never done anything like this before). We candled the eggs at Day 7 and again at Days 11 and 12 (after the temperature in the incubator became unstable).

At Day 13, we confirmed two very active embryos (and 2 yolkers) before transferring the developing eggs to my mother's hen, which fortuitously, had meantime become fervently broody!

My question is in regards to one of the two developing eggs - our 'special needs' egg. After candling on Day 7, we discovered that it had the air sac at the pointy end of the egg! The eggs were not shipped - I picked them up from a local supplier whose ducks live nearby. We weren't sure how we should place this egg in the incubator so just lay it on its side. We placed the other normal egg with the blunt (large) end slightly elevated. Both eggs were turned by hand 5 times a day.

We haven't candles the eggs since the hen took them on at Day 13, but if all has continued to go well, the ducklings will be due to hatch on the 27th of December (today is day 24).

I'm really nervous about our 'special needs' egg and wonder if it's safer to leave this egg under the hen for hatching, or whether we should take it back on Day 26 or so, to monitor it in the incubator, in case we need to assist it in hatching. Any advice would be very much appreciated!
@kiwichicks Welcome to BYC

I am going to tag some members for you who have experience with hatching and problems
@WVduckchick

@caesargirl
 
If it was a good air sac on the small end, there is a good chance it will hatch as it would from the other end. It really depends on whether the duckling positions itself right when the time comes.
I've not had experience with this, so I'm only guessing.

Does the hen let you near her or does she keep you away? I'm wondering if you could candle again and see if you can tell the positioning now.
 
Wonderful - thanks for your help
smile.png
 
Yes, I was thinking about candling again - I just haven't yet as it's a bit of a drive out to my mother's place, where the duck eggs and hen are. The hen gets a little cross and pecks when we disturb her, but it's easy enough to get the eggs. I'll let you know what we see if we manage to get there before Christmas. Thanks!
 
Ok, I have now candled the eggs - on Day 25 and 27. Unfortunately things don't look good at all. The egg with the air sac at the pointy end looks particularly strange, with the chick appearing to take up only 1/3 to 1/2 of the egg along the long axis!! When looking at it yesterday, we had almost decided not to put it back under the hen when we saw movement at the very tip of the egg - possibly a beak moving? I've attached a picture that I drew to try and show what we saw:
I don't know if it's still alive, but will try and take another look today. The other egg, looked like the one below on Day 25. However yesterday (Day 27), the veining seemed to have disappeared, there was no movement and there was lots of fluid and 'floating bits and pieces' in the fluid. I'm guessing this chick has died for some reason and everything is disintegrating.
Is there anything we can or should do with the egg drawn above, if we still see movement today? It just looks so 'wrong' I can't imagine we have any hope...?
It's very upsetting as the embryos looked great when we transferred the eggs to the broody hen on Day 13 and she has 'sat tight' the whole time apart from leaving the nest for very short spells in order to eat, every couple of days or so.

Other 'good' egg:

 
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Not seeing veins at this point is not abnormal. Its time for them to start pipping and emerging, so that's not a bad sign.
I'm concerned about the odd shapen one, although it is possible that what you "think" you see may not be exactly what is really going on. I'm not trying to be mean, its just the denseness of everything in there can be deceiving.
At this point, my recommendation would be to leave them with the hen and hope for the best. Your concern is admirable, but I don't think you are risking anything by leaving them be. Just keep a watch, like it sounds like you have been doing.
 
If I had to take a guess, based on what ha happened to me in the past, that empty space is filled with sticky goo. It's like rubber cement only stickier and thicker. IF that's what it is, it has taken up space meant for the duckling and can cause the baby to not grow correctly.
And yes, it's not unusual for veins to disappear at this stage. If you look for movement in the half and half egg, try the float test. Using a deepish bowl filled with warm water, put the egg in it and look to see if the egg moves, it might be very slight movement. At this stage, there might be a few things you could try, but try the float test first. Let me know...
 
Thanks very much VWduckchick - I feel a bit better now. My biggest concern for the 'good' egg was the complete lack of movement and the fact that there is now a significant amount of fluid between the dark mass at the bottom and the air sac above - with lots of dark 'floaties' moving freely in the fluid when we turn the egg.

With regards to the odd shaped egg, what I probably didn't show or explain properly was that when candling, the light shines completely through the rest of the egg (the bit that I didn't shade in my diagram) - it is perfectly clear, as if it is a huge misshapen air sac. In fact there is no demarcation between the original air sac at the pointy end and the rest of the empty space in the egg - almost as if the two spaces have merged. After a bit of reading here, I wonder whether the chorioallantoic membrane didn't develop property and extend to line the inside of the entire shell, but instead was arrested in its development and effectively 'cut' the egg in half, leaving a very small space for the duckling to grow. Pure speculation of course, especially as I'm a complete novice!!.

If the duckling is indeed trying to pip internally, I can't see how it could manage this process normally. If things stay the same over the next day or so, do you think it's worth making a tiny breathing hole at the pointy end of the egg where the air sac is/was and where I saw the shadowing/movement?

I'm probably sounding completely paranoid (but we SO wanted to get at least one duckling!!).
 
Great, thanks Caesargirl - I'll definitely give it a try and let you know! As I mentioned to WVduckchick, it is the amount of fluid that is now showing along with lots of dark 'floating' material (bits and pieces) that is really worrying me. But the float test sounds really helpful - thanks! And the sticky goo that you talk about in the other egg makes sense with what I'm seeing. In this case, do you think there would be any benefit to helping this duckling out, or is it likely to die (or be malformed) no matter what?
 

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