Day 21 and no pips

[Tvan18]

What should the humidity have been at early in the hatch? I had read between 50-60% so that was where I tried to maintain it, usually with it sitting right in the middle at 55%. I’m wondering if I made a mistake there possibly and kept it too low then? I took notes and my temp held steady the whole 21 days between 99.5°f and 100.5°f. The humidity was a little more difficult to keep up at first and I had to try a couple methods, but it was never below 45% and I was able to bring it back up quickly that time.

 

[HollowOfWisps]

Exactly what @Ridgerunner said. It’s the humidity that is the issue not the temperature. Yes hens do get off of the nest all of the time, but the humidity under the hens is fairly similar to the outdoor humidity. I took several pre-calibrated hygrometers and put them under my broody hens last year to see just how much humidity difference there was. The answer was not much. The ambient outdoor humidity was almost that of the humidity under the hen. When using an incubator many people tend to run the humidity much higher than the ambient humidity of the room. When the eggs go from a higher humidity in the incubator to being exposed to low humidity in the room that is when the eggs are at the highest risk for shrink wrapping. With the right conditions it creates essentially a humidity vacuum. Think of it like being on plane. When you fly the air is very very dry compared to what you are exposed to on the ground. That is why many people feel like every ounce of moisture is being sucked out of their skin because it essentially is. When a hen is brooding outside that humidity difference between under her and outside is considerably less drastic. That is also why someone dry incubating would have a lower risk of shrink wrapping due to the humidity being similar if not the same to that of the room.

 

[Iluveggers]

@Tvan18 did you calibrate a separate thermometer and put it in your incubator? I am wondering if your incubator could be running a bit cold. Not cold enough to kill your chicks, but cold enough to cause them to grow a little slower…

 

[Tvan18]

I did. I had 2 separate thermometers and one also included a hygrometer as well. The thermometer was kept on top of the eggs and therm./hygro. Was kept on the tray next to the eggs. I took the thermometer on top the eggs as most accurate to what the eggs would be running.

 

[Tvan18]

The thermometer built into the incubator did seem to run lower than the 2 I put inside by quite a bit so I rarely paid that one much attention.

 

[BarnyardChaos]

What should the humidity have been at early in the hatch? I had read between 50-60% so that was where I tried to maintain it, usually with it sitting right in the middle at 55%. I’m wondering if I made a mistake there possibly and kept it too low then? I took notes and my temp held steady the whole 21 days between 99.5°f and 100.5°f. The humidity was a little more difficult to keep up at first and I had to try a couple methods, but it was never below 45% and I was able to bring it back up quickly that time.

Standard recommendations are humidity for Days 1-18 should be between 30-50%, and for Days 19-hatch between 70-80%.

It's not as critical during the first 18 days, as you WANT some of the fluid from the egg to evaporate, thereby creating a large enough air sac for the chick to breathe once it internally pips. Some folks even do a "dry hatch" with no additional moisture at all; just ambient levels. So lower humidity is FINE during this stage.

I believe that too high humidity throughout the incubation period leads to too small an air sac, and the possibility of chicks drowning or suffocating inside the shell before they hatch. If they can externally pip, I turn the egg so that the pip hole is turned upward until they begin to zip.

But during the last 3 days, higher humidity is warranted to prevent shrink-wrapping.

Please, experts, correct me if I'm wrong.

 

[Ridgerunner]

What should the humidity have been at early in the hatch?

I personally do not believe there is one perfect humidity for everyone incubating in the world. Incubators are different and that goes beyond forced air versus still air. The temperature and humidity of the air going into the incubator from the room can vary depending in where in the rood the incubator is located. Elevation above sea level due to air pressure can make a difference. Just so many variables.

The purpose of humidity during the incubation phase is to allow the right amount of moisture to evaporate through the porous shell so the air cell is the right size at hatch. Too high a humidity and the air cell will be too small. Humidity too low and the air cell is too big. Both situations can cause problems.

Something that makes this more challenging is that not all eggs are the same when they go in the incubator. Some have more porosity than others. Some have thicker or thinner egg whites. An egg that has been stored for a while in a low humidity environment can lose a lot of moisture before incubation even starts compared to a fresh egg. There are other differences. It all sounds pretty hopeless but it isn't. Naure was kind enough to give us a pretty wide window of moisture loss that will work. The closer you are to your perfect midpoint the better, but you can be a fair amount off and still get good hatches.

So what do I recommend? Pick a humidity and be as consistent as you can be. It's not always easy. If your incubator instructions have a recommendation I'd start there. Is that where you got your 55%? Then evaluate your results. I'll include a couple of links to troubleshooting guides to help with that but that is not always easy.

Incubation Troubleshooting - Incubation and Embryology - University of Illinois Extension

Trouble Shooting Failures with Egg Incubation | Mississippi State University Extension Service (msstate.edu)

My incubator recommended 45% so I tried that and got pretty good hatches. After a few hatches I determined my sweet spot was around 40%. I hatch about 20 chicks at a time. The difference in 45% to 40% humidity was an average of maybe 1 chick per hatch at most. Not a lot of difference but I'll take what I can get.

Some people do great at 55%, some do better around 30%. I'm convinced there is no one humidity that works best for all of us. Good luck on finding yours.

 

[Tvan18]

Thank you, this is very helpful. Yes I got the humidity range from the incubator instructions.

 

[Tvan18]

We started hearing chirps last night and tonight I have one external pip, and one that looks to be trying for sure. Then 2 that have “moved” Patiently waiting to see how things go! The Maran egg looking to be pipping is the one we sealed with wax when it had gotten dropped and accidentally cracked during candling day 16.

 

[Tvan18]

Since what looked to be the start of the external pip on my Maran egg it hasn’t progressed at all. The piece of shell are still just cracked/pushed up, but not actually open. How long do I wait before I should maybe at least use a tweezer to take those 2 small pieces off? Just nervous for that chick since it’s the cracked one I tried to seal. I don’t want it to fry out.