It’s probably an incubation/ humidity issue but if you know what this is or how to fix it please let me know I’m desperate!
Hi there, hope you are enjoying BYC!
I'm going to provide you with some excellent resources. But you will have to do the research to dial in YOUR conditions and discern exactly what you are seeing because many things can APPEAR similar but have very different causes or fixes.
What you describe is NOT relative to yolk sac.. and more likely on par with
sticky chick than mushy chick syndrome.. in MY experience.
Yes.. either temperature/humidity related from incubation.. but always pay attention to other things.. such as individual layer, egg storage conditions, etc..
My favorite incubation resource with cause for hatch failure starting around page 52..
Incubation guide
I found that resource and lots of other information in the following thread which has some outdated links but tons of valid information and continues to be updated..
Hatching Eggs 101
And another hatch analysis resource with GREAT information..
Hatchability Problem
*Possible* fixes.. move eggs around inside incubator daily.. to combat any temperature differences and spread them out.. resulting in tighter hatch frame.
Are these STICKY chicks.. hatching on day 21.. earlier or later? A different colored egg or breed than others? If others are hatching normal, and only one or two are not then
maybe the egg condition is more relative than the incubation'hatching parameters??
Although friendly lurkers, heart is in the right place.. I'm not sure their suggestion is valid.. or if it will help or make matters worse. I do solidly and
humbly disagree with their assessment having hatched hundreds of chicks.. but I could be way off as well! So with anything.. please use YOUR best judgement.
https://www.chickenwhisperermagazine.com/health-and-wellness/the-art-of-incubation
FWIW sticky chicks is caused by humidity already being too high.
Although the gunk left over and dried on looks yellowish.. it is NOT yolk. But it's easy to see how it could be mistaken for such.