Hatching How To: Things I wish I had known
Hatching chicks is a fun and rewarding way to add to your flocks. I have been on the receiving and sending end of hatching eggs, and know that incubation is a skill that is very rewarding. Learning the ins and outs of incubating is something that is done through many sets of eggs. A great way to start learning to hatch is to get fertilized eggs from your own coop if you have a rooster, or from a local farm that has fertilized eggs that you can practice with. Fresh, non-shipped eggs are the easiest to hatch, because the eggs themselves do not go through the trauma from shipping and handling. This automatically increases hatch rate. Once your comfortable hatching, shipped eggs are an amazing way to add birds of different breeds and genetic lines to your flock! This article will be for chicken eggs, however, these same things can apply to other species of fowl.
Some general facts and terms about hatching that will be used throughout this article:
- Chicken eggs take 21 days to hatch
- Developmental stage is day 1-18
- Lockdown stage is day 18-21
- Internal pip- when the chick breaks through into the internal aircell of the egg
- External pip- when the chick breaks through into the external egg shell
I will go over some of the most integral portions of incubation. These next sections are all things I’ve learned from experience hatching thousands of eggs.
Humidity:
This is an extremely important part of hatching. Most of the issues that I see from people comes from fluctuations in humidity. There is a lot of suggestions on humidity for hatching, but in my personal experience, figuring out your humidity in your house/building where your incubator is essential. Steady humidity is the most important, and if the humidity around your incubator is steady at 35-45%, one option is to just allow that to be the setting for your eggs. If it is under 50% humidity, that is perfectly acceptable and easier to be consistent. The last 3 days (lock down: day 18-21) the humidity should be increased to at least 65% to make hatching easier on the chicks. A secondary hygrometer is strongly recommended to make sure that the reading is accurate.
What if the humidity is too high:
Eggs have aircells in the ‘big’ end of the egg that is responsible for allowing the chick to breath when it internally pips. In order to form the aircell, moisture/fluid has to leave the egg. If your humidity is too high throughout development, and not enough fluid has left the egg the aircell will be very small. If it is too small, the chick will not be able to breath during hatch and will drown.
When looking at what went wrong with a hatch high humidity will present as one of 3 main things: a perfectly developed chick that never hatched, very sticky/goopy covered chicks, and low hatch rates with weak chicks.
What if the humidity is too low:
Lower humidity is ok throughout the hatch and may not be the worst thing. However, if the aircell gets too big the chick can run out of room and may not develop properly. This can lead to lower hatch rate. I have found this to be more of an issue with light colored eggs, such as blue, white, and cream eggs. The dark eggs like the chocolate eggs the Black Copper Marans lay, do much better with low humidity because their shells are very thick and sometimes have trouble loosing moisture.
Low humidity during lock down, is where trouble arises mostly. If there is not enough humidity(65% and up) the chicks can get stuck in the shells. As the chick “zips”(chips away at the outside of the shell), the membrane inside is exposed. If that membrane drys out it becomes almost leathery. It is very hard for the chick to break through that. The area along the ‘zip’ can start sticking to the chicks feathers. There are 2 membranes, an internal and external. The internal membrane can shrink around the chick if the humidity is low. This is also know as “shrink wrapping”. The chick is essentially stuck in the egg and unable to rotate to hatch. Unless intervention is done, the chick has a slim chance of hatching. I will do another article on assisting a shrink wrapped chick.
Temperature:
Consistency is key again for temperature, which should be kept at 99.6-100.1. On the same note as humidity, a secondary thermometer is highly suggested! There are combination meters that do both temperature and humidity all in one. They are great and usually inexpensive. One thing to note is that the temperature reading on the digital incubators can be off, and even a degree or two can have major effects on your hatch.
If the temperature is too low:
When the temperature drops below 99.5, several things can happen. The biggest thing is that it slows development of the chicks. This can lead to deformations or early death of the chicks. Low hatch rates are very likely. If the temperature is too low during the first 18 days, the chicks can be delayed in hatching. This will lead to chicks possibly hatching on day 22 and above. When incubating a set of eggs, I highly recommend not taking any eggs out until day 24-26. This will give adequate time for the stragglers to hatch. If chicks hatch later than 21 days, they can be weak or malformed so keep that in mind.
If the temperature is too high:
A temperature above 100.1 can cause a whole other set of issues. Whereas low temperatures delay development, high temperatures can accelerate development. Making chicks faster doesn’t sound that bad right? Unfortunately that’s not the case. Some of the development issues that can arise are super weak chicks, yolk sacs that do not get fully absorbed before hatching(also exposed insides), splay legs, and other issues. If the temperature gets too high, some if not all of the embryos will not be viable.
Rotation:
An incubator with automatic rotation is a lifesaver! Seriously, the best feature you can have on an incubator. Eggs need to be turned multiple times a day. A mother hen that is sitting on eggs is consistently rolling and moving her eggs. Inside an incubator, this needs to be replicated. The purpose of rotating the eggs is actually very interesting. If an egg is not rotated or moved at all during the development phase (first 18 days) the chicks can get stuck on one side of the egg and not be able to turn to get into position to hatch. This will lead to low hatch rates. On the flipside, too much motion is not good either. There are tiny blood vessels that form inside the egg as the chick grow. Too much motion can rupture these vessels and cause losses. Eggs should be turned a minimum of 3 times a day, and up to 5 times a day.
Lockdown:
This is an affectionate term to describe the last 3 days of incubation, day 18-21. A lot of issues occur in this small amount of time. The number one tip I can give anybody on the lockdown time frame is:
DO NOT OPEN THE INCUBATOR!!!!!!!!!
Yes, that was me yelling a bit.. I apologize. However, this is where I see great hatches go bad really fast. For some context, a mother hen does not leave her nest the last 3 days of the hatch, or if she does it very rare. This is because constant temperature and humidity need to be maintained. Opening the incubator drops the temperature and the humidity rapidly. This is the number one cause of shrink wrapped chicks. During the last day the chick will absorb the yolk sac inside their eggs. This gives the chick enough nutrition for at least 72 hours after hatching. The first chick that hatches is perfectly fine staying inside the incubator until the last chick hatches. Yes, it will roll all the other eggs around and not be gentle about it. This is fine, great even, because it will stimulate the other chicks to hatch. 72 hours after the first chick is hatched, and no other eggs are pipped, it is safe to remove the chicks. A lot more chicks are lost by prematurely opening the incubator than delayed removal. If you learn nothing from this article, please at least listen to this paragraph. It is the biggest make or break time frame of your hatch. Baby chicks are adorable and fluffy, but I promise you, they are just fine staying in the incubator until their friends join them.
Conclusion:
There are so many factors that go into hatching eggs. These are just the biggest issues that I see affecting hatch rates. Keep in mind 100% hatch rates are not easy to get. I’ve only had that luck a few times. If you need a set amount of chicks I always recommend setting 10-20% extra eggs to make up for a few losses or eggs that are duds. Another thing to think about is eggs are not able to be sexed. You will end up with 50/50 rooster and pullet chicks.
Keep all these things in mind if you start the journey of incubation. Happy Hatching!