air cell and humidity????

[Anonymous]

I am incubating a duck egg, and it is close to hatching (within 4-5 days). The air sac is about 1/2 the size it should be. Is this due to too high humidity or too low?? When I candled yesterday the egg is full and the air sac is all that can be seen. There is still movement. We are on day 31 and I don't know how to tell when I should stop turning the egg. What do I look for? How do I guage when it is 3 days until hatching when we are 3 days past due date now? Any help anyone could give me would be great. This is my first time incubating. Please help, what do I do??

Temp. is 101.5-102 (still air)
Rel. humidity is around 60-66%

Thanks, Lucky Ducky

 

[Tim]

Hi there,

Normally if they run over, the temperature is too low and they might not hatch correctly or be healthy if they make it.

If the air cell is small, it means there hasn't been enough evaporation of moisture from the egg and therefore the air outside the egg has been too humid.

I would also back this up from your measurement of 60 - 66% that this is too high. The text book humidity for duck eggs is 40 - 50% but some breeders do not add water at all. It depends on the porosity of the shell and some breeds (especially some Geese) don't seem to lose enough moisture when water is added / the air is more humid. There is always the natural outdoor air humidity that goes into the incubator.

Some will say they can only incubate certain exhibition Waterfowl eggs by a broody hen / goose and even they fail in wet summers...

Good luck, I hope you have some success although I hate to say that they are quite likely to die in the shell if they haven't pipped by now.

Please let us know how you get on. Tim

 

[Anonymous]

Thank you for response. I read that for ducks humidity should be 60-65%. I read just the opposite about keeping humidity, it was a must. Good to know. There was movement in egg yesterday, this whole thing has been such a long shot. It's whole development has been behind. I haven't given up hope just yet, but I understand the reality. Thank you so much for answering. I really appreciate it.

 

[Tim]

Yes, the advice varies dramatically from book to book. Some even advise spraying the eggs with tepid water from time to time.

Let us know how you get on, have they pipped? I have 7 eggs due on Sunday (Day 28) and 4 out of 7 have pipped now so they can breathe.

Tim

 

[Anonymous]

No they haven't pipped yet. Please help me with this question-when do I stop turning? Just before they internally pip, or when they do pip? I know they are overdue, but I'm acting as if. Please help with question. I will let you know how it all ends. Good luck with your ducklings.

 

[Anonymous]

My little dukling died without hatching. Thank you for all your help. I'm glad I found this forum and hope it will be here for future use.

 

[Tim]

Oh sorry. It's been a busy weekend and I missed your post.

Normally you would stop turning them for the last 3 days and raise the humidity. I run a separate hatcher here and from time to time, I forget an egg or two and find a few ducklings running about the incubator having been turned all the way to the end!

They should pip a little before hatching - sometimes up to 48 hours before but more often 24 hours or less before hatching.

I hope you have better luck on your next batch. It's a learning curve but once you get it right, it's really satisfying.

Good Luck. Tim