Incubator has varying temps - now what?!

[Aussie Fluff]

We set 26 Australorp eggs 12 days ago in a forced air Janoel incubator. We have only done two hatches in it so far so we're still pretty new to this.
The temp was set at 37.5 and the humidity around 40-45%. Before setting the eggs we checked the temp using two different external thermometers and they were between 37.5 and 37.8 which was fine.

After candling them on days 7 and 10, I noticed that quite a lot of them seemed to have blood rings/had stopped developing, which I thought was a bit strange seeing as the eggs had been stored perfectly before setting and came from good breeding chooks etc.

I thought maybe something was wrong with the temp, and after checking six different areas inside the incubator I was definitely right! One part in the middle/front section was reading 37.5, while the rest of the incubator was reading between 38.9 and 40.1!!
Straight away I took the lid off to cool everything down a bit, and altered the temp on the incubator. Most areas are now reading around 37.3 and 38, which is the best I can get it for the remainder of this batch. We will obviously try and rectify it properly before the next batch.

The problem we now have is that some are ahead in development while a couple of the others are way behind how do we work around this when it comes to lockdown? Do we just start lockdown on day 18 as planned and give the others an extra few days to hatch, do we have to start lockdown earlier because of the ones that are further ahead? It has taken us months to finally find a decent Australorp breeder with fertile eggs and their hens are going broody and not laying much anymore, so we really don't want to lose this batch!

 

[als77]

I'm a noob, but a higher temperature (than 37.5C) means that they will hatch sooner, not later. So if you planned on lockdown on day 18, then you shouldn't do lockdown later than planned (if any change, then sooner).

Hopefully some of the veterans will chime in

 

[Aussie Fluff]

I'm a noob, but a higher temperature (than 37.5C) means that they will hatch sooner, not later. So if you planned on lockdown on day 18, then you shouldn't do lockdown later than planned (if any change, then sooner).

Hopefully some of the veterans will chime in

Yep some of them are ahead in development as they were sitting in the warmer spots in the incubator, but there were some that were sitting in the cooler part so they are behind n development compared to the others.

So I'm just asking how to work lockdown around the ones that are behind, as they won't be ready for the higher humidity level as early as the others

 

[jher77]

I'd say plan on doing lockdown on day 18 as you planned, but keep an eye out for any pips before then. If you do get a pip before lockdown, then lockdown right then and raise the humidity.

 

[Mellowmalt]

you can always swap the eggs around so the ones that are ahead will fall behind and the ones that are behind will catch up. Since you have gained space in the incubator try to see if you can rearrange the eggs to avoid any hot corners thogh. The ideal temperature is between 37 and 37.5 degrees C. Avoid anything over 37.6 for prolonged periods. A fraction of a degree lower is always better than a fraction higher.

PS: if you had problems with the temperature now you will always have problems in future but it could be that your room temperature was colder this time than previous times which on more basic incubators will have more of an effect.