Dry incubation.

[LittleMoss]

Hi,
We're just incubating for the second time, the first time went badly, and now we're trying dry incubation. We'd read about 30-40% humidity for incubation and 60%+ for hatching. Our incubator is fan-operated, and we don't seem to be able to achieve 30-40% - if we put the smallest amount of water in it goes up to about 60% and then comes down after a while. Otherwise it's about 27%. Is this okay? I'm worried we're going to have another bad hatch, but with different problems from last time...
Thanks for any reassurance or advice!

 

[feedman77]

I don't worry about humidity unless it's below 20 percent.

You will be fine at 27 percent.

For hatching I try to jump my humidity to 70 plus.

Not sure what incubator you have but most humidity gauges are off in them.

I just did a hatch. Had 3 incubators running. All in same room. The readings ranged from 16 to 35. All were run dry.

They were a brinsea, a 1588 genesis and a 1502 sportsman. These are some better incubators but all varied.

 

[moving coops]

Yes, I don't know what to think with humidity, my sportsmans says 35% on digital display but my hydrometers in side say 25 and 27!

 

[Heron's Nest Farm]

I live in Oregon and although it's raining it's dry in winter.

That being said, I have the best luck with hatching here when I put 1/4 cup water in when I put the eggs in to incubate and 1/8 cup at 14 days. I do a completely dry hatch. There is plenty of humidity that happens when birds start hatching. I have had chicks drown in hatches with over 20 eggs when I had the humidity up because teh humidity would jump so high from hatching chicks!

Also, I am hatching in The 48 egg hatchers so I can't speak for large cabinet hatches.

 

[Bantu]

Here in Arkansas in winter mine is 20-22% with no water at all.
Right now it's running at 23 %.air cells right where they should be.

 

[LittleMoss]

I'm planning to candle the eggs this evening, because I set them on Saturday evening, so that should be five days. I've just been reading a different thread, and somebody was talking about checking where the air sac is before lockdown (I know that's not yet!) - is it best to check that the air sac is at the the top before lockdown?

 

[Bantu]

If the air cells are not in the large end of the eggs they most likely won't hatch at all.
I candle at 10 and lock down. The more you handle the greater the risk of killing the chicks in my opinion. I wear sterile gloves when I candle and I sanitize the flashlight I use to protect from bacteria.
I check air cells at day 10 and if too big I add humidity if too small I reduce humidity. (There is a air cell chart you can follow). I candle at lockdown to check for late death chicks, ( usually from bacteria when it happens, again my opinion).
If the egg shells are brown you might not see much until day 7 or so. So I say if you want to see what is going on in those eggs go ahead and candle at day 5 but I wouldn't candle again until day 14 and lock down.

My system is dry incubation humidity around 22%.
Candle at day 10 and lockdown
My hatches have gone from 0% the first two attempts
To 75% and 100% just hatched yesterday ( my own eggs, not shipped).

 

[Egghead_Jr]

Yes, I don't know what to think with humidity, my sportsmans says 35% on digital display but my hydrometers in side say 25 and 27!

Humidity gauges mean little unless they are calibrated. Rule of thumb is to never look at any gauge that comes with the incubator. I've seen readings 15% RH off from actual. You must calibrate a gauge then the readings they give mean something. Once you've a calibrated instrument it can be compared to what's attached to your incubator to calibrate that. Masking tape to write down how far off the reading is and afix to incubator as a reminder.

Salt Test to calibrate:

Fill a milk jug cap (any small container) with salt and add drops of water until saturated. I pour off any standing water.

Put hygrometer and salt cap in a sealed container. I use zip lock bag. Wait at least 4 hours and 6-8 is better- depends on how much salt used and size of container.

After time period, hygrometer is stable and not moved in some time, record the reading. A salt environment will is exactly 75% RH. However off your reading is is your calibration number.

Subtract your reading from 75 and write that number on tape to affix to incubator. Example, your reading is 84; 75-84= -9. You'll always -9 from your reading to be true RH.

 

[LittleMoss]

Thanks, that's really helpful, the salt test sounds like a great science experiment too. I think we won't bother with candling - we don't have a proper candler, and having tried looking through a different egg with our flashlight, are not confident we'd see a lot anyway. I think I'll leave the incubator eggs in peace.

 

[LittleMoss]

I've just tried candling (day 7). The room probably wasn't dark enough, and I was just using a flashlight. I really couldn't see a lot! We have some white and some brown eggs. In the white ones, I could see something dark and flat-looking at one side of each egg. In the brown ones I couldn't see anything. I've also weighed the eggs - I weighed them before incubating, because I have a book which gives a formula for the percentage weight loss per day, for good air sac development. They all seem to be a good weight - does anybody else ever weigh eggs? Can I take this as a good sign? Maybe I should try candling again on day 10, and do when it's darker.