huge failure to thrive ratio out of this last hatch, help!

[wildsequoia]

So I set guinea eggs last month and waited five days and set some chicken eggs. This is the third time to use this incubator this year and I have had little problems with hatch rate. I normally have one or two that never come out and die in the egg. But this time I had 9 out of 23! some chicken and some guinea. Of course I am devastated! Opening up the eggs to see full grown chicks dead in their eggs. can I get some advice as to what may be a reason to cause this? Maybe my incubator was not cleaned well enough? I kept the temp right at 99 and the humidity between 60-71 (depending on how many were drying off) for lockdown. Thank you for any advice!

 

[howfunkyisurchicken]

Just a suggestion, but maybe you should try dry hatching and see if your hatch rates improve. My Silkie eggs struggle if I incubate them at the 50% humidity recommended by my bators instructions, which is still quite a bit lower than your 60-70%. I'd have a ton of dead in shell. They pip through the membrane, into the air cell and then just die (I assume because they're drowning in moisture inside the air cell, caused by the high humidity).

I started keeping my humidity between 25-35%, or as low as I can possible get it, depending on how humid it is outside, for the first 18 days. I bump it up to around 60-65% during lockdown. My hatch rates have improved drastically!

Before, I was having one or two chicks hatch (out of 30 or 40 eggs). Pretty much all of them would die just before hatching, but after they made it into the air cell. My last hatch, I set 24 eggs. Just 2 didn't hatch, and they quit well before lockdown.
If you do a BYC search on dry hatching, there are several threads about it if you'd like to read up first.

Good luck!