Developing embryos and increasing bator temps.

[jmc]

Fact:

growing embryos generate (some) heat of themselves.

I have two Brinsea oct. eco bators with 20 and 21 eggs in each.......IOW, almost full.

I don't know if the eggs are acting as thermal mass or it is the developing embryos, but the fuller bator seems to run a bit warmer than one that has just a few eggs in it.

I recently did a run with 5 eggs in each bator, and it didn't seem that the eggs/embryos affected temps much..............

The development i am seeing now in the embryos in these NEARLY FULL bators seems much more advanced than the embryos i had at the same age in bators with only 5 eggs in them.

These embryos just seem to me to be a bit ahead of schedule. Both bators were calibrated by Brinsea Spot Check therm to 99.5 at mid egg level beneath bator fan.

Also even with RH at 40-45 %, at just day 7 the eggs seem to weigh too little

if you need me to explain myself more, i can.

 

[jmc]

i tend to ask rather 'rarified' and difficult questions!!!

 

[ChickenCanoe]

I'm a bit rarified myself - about everything.
In answer to your question, I imagine it's a little bit of both. A full bator will have smaller temperature swings, like a full freezer.
Chicks have a high body temp albeit small mass. I'm sure they don't begin to generate heat as 2 day olds but that it starts mid to late incubation.

 

[Ridgerunner]

I agree added thermal mass helps minimize temperature swings. I'd expect those Brinsea to be pretty good about keeping the heat right. I just don't see how more eggs would increase the temperature, especially early on. If they do generate any heat, I'd expect the Brinsea thermostat to just not turn on the heater as early.

Are you sure other conditions are the same for your comparison? Did you store them the same length of time and in the same conditions before you started them? Is the heat and especially humidity in the incubation room the same as your former time. The weight of the eggs doesn't mean a lot if there is a starting weight difference in the eggs. It is the percentage weight loss you need to look at. And the longer you store them in dry conditions the more that weight loss will be before you even start.

Incubation has a lot of different things involved. You can't really just look at one factor in isolation but need to look at all possible factors. Sometimes that can be challenging especially for someone not there looking at your process. I can only guess.

 

[ChickenCanoe]

Agreed. Ambient temperature has a lot to do with it.

 

[jmc]

thanks to you fellow rarified folks. I don't feel so alone!

conditions are almost identical, with the exception of the no. of eggs.

same ambient temp.
and overall the ambient RH has been basically the same/very similar.

Yes, i look at the percentage of weight loss in my practice, and the eggs are so far losing weight faster than they should be.

anyway, this may be much ado about nothing. i just wanted to air the thought out.

will be interesting to see how or IF the hatch goes on the 12th, or ...................earlier................

I ALSO HAVE TO ADD THAT I HAVE ONLY ONE INCUBATION EXPERIENCE UNDER MY BELT. SO AS I GET MORE EXPERIENCE MAYBE I'LL FIND OUT THAT WHAT IS HAPPENING IS 'NORMAL' FOR MY PARTICULAR SETTING.

thank you, gentlemen

 

[dulcelife]

Quote:
Chicken embryos shift from poikilotherm (temp regulated by environment), to homeotherm (generating their own heat), beginning within the
last 20% of incubation or around day 16 or so. This is assuming a steady temp of 38 C. So, I doubt the eggs are contributing heat of their own.

 

[cmom]

I don't think the eggs are contributing heat of their own either. I do agree that the more eggs in the incubator the more stable the temperature. When I incubate I try to pretty much fill it. If I don't have enough eggs, I put some bottles of water in to take up space. I have found I have less of a temperature swing then with fewer eggs. My incubator holds 324 eggs. I have a friend who contributes eggs too.