Eggs fertile , fully developed but don't hatch

[PenrodHill]

So I've been incubating my own eggs for a number of years now . I have a sportsman cabinet style incubator which actually does a great job at maintaining a constant temperature etc .
My best hatches are probably close to 75% with more being in the 50 - 60% range . If I crack open my unhatched, unpipped eggs after everyone is done hatching most of them will contain a fully developed dead chick , who for whatever reason opted to not peck its way out of the shell . I would guess my fertile , developed chick rate to be close to 90% .
Is this something I have to accept as normal ? Or do I need to do some adjusting to the temp, the humidity or something else ?

 

[ChickenCanoe]

75% isn't terrible. Did they hatch early, late, on time or protracted?
If not on time, I'd look at calibrating.
Did you turn religiously from the day of collection?
If they were on time. I'd look at boosting breeder nutrition.
It could also be heredity,

 

[PenrodHill]

Yeah I got an automatic turner .
They have been early in the past and I cooled things down a bit which pushed them to 21 days and did seem to help my hatching rate . Still, it's painful to see all these expired chicks .

 

[ChickenCanoe]

The first rule of hatching is to guarantee the temperature is exactly 99.5 in a forced air and 100.5 at the top of the egg in a still air.

 

[wleigh1021]

if they're not pipping I'd think it could probably be shrink wrapping. What is your humidity like in lockdown? Do you use a separate hygrometer to double check that it is correct?

 

[Shamo Hybrid]

Out of around 2 dozen eggs, all of mine hatch minus one that pipped but just lost strength to continue further. But with yours, there is definitely something else at play. I would suggest dropping 2 degrees during lockdown or a day to 2 days before expected hatch date.

 

[Mosey2003]

From experience, I'd guess humidity is at 60% plus. Get it to stay between 50-55% with an independently verified hygrometer or wet bulb. Also, ensure your air flow is appropriate, your vents should be open about the width that you can fit a pencil in.

Of course, bump it to 65% at and through lockdown.

 

[PenrodHill]

I just learned how to calibrate or check a hygrometer ( I use digital ) , so I'll definitely being doing that . Here in Ohio it's often humid with a lot of ups and downs so regulating the humidity is a constant stress .
Something interesting I once read is that hens communicate with their chicks in shell and encourage them to pip and keep going and not give up ... could I find this recording on iTunes ...?
So for the hatch we want the humidity high but we also need oxygen for the hatching chicks . And the bigger the vents are open the lower the humidity drops... tips for managing this scenario ?

 

[Mosey2003]

I just learned how to calibrate or check a hygrometer ( I use digital ) , so I'll definitely being doing that . Here in Ohio it's often humid with a lot of ups and downs so regulating the humidity is a constant stress .
Something interesting I once read is that hens communicate with their chicks in shell and encourage them to pip and keep going and not give up ... could I find this recording on iTunes ...?
So for the hatch we want the humidity high but we also need oxygen for the hatching chicks . And the bigger the vents are open the lower the humidity drops... tips for managing this scenario ?

Managing the humidity in your hatching room can really help as well, if it's super dry or super humid, that will affect the humidity inside the incubator.

I don't think a recording is really necessary, but never know what you'll find on YouTube.

You're just gonna have to play with your incubator and environment to see what the humidity is with the vents open about 1/2". That will determine how much water you add, etc. If your hatching room stays over 55% humidity you may want to run a dehumidifier in there. But yes, the first step is to determine for sure just what the accurate temperature and humidity are.

 

[PenrodHill]

if they're not pipping I'd think it could probably be shrink wrapping. What is your humidity like in lockdown? Do you use a separate hygrometer to double check that it is correct?

What do you mean by shrink wrapping ?