Learn how to hatch a chicken egg at home, the importance of incubator temperature and humidity for chicken eggs, and when to move to incubation.
Believe it or not, the nursery isn’t just an invention of the modern age. Historical records show that egg incubation was practiced in ancient Egypt. The mud-brick buildings were divided into rooms which were essentially large ovens, and heated by burning straw, dung or coal. Temperature and ventilation were regulated by opening doors and louvres to let smoke and light out. Moisture was provided by moistened jute placed near and on top of the eggs. There must have been a lot of guesswork and trial and error involved in successful shadowing, and hopefully the success rates are high enough to make the effort worth it.
Easy modern incubators
Fortunately, modern incubators take a lot of the guesswork out of the incubator, maintaining constant temperature and humidity effortlessly, with a little bit of good management. Even the simplest incubators have thermostats and water tanks. More sophisticated incubator systems have sensors that can record humidity levels and add water accordingly.
We all know that temperature and humidity are critical to successful incubation and hatching. But did you know that long before that egg you’re about to lay in your incubator becomes a fluffy, feathered chick, it’s still a living, breathing organism?
evaporation incubator
Pores in the shell allow gas exchange as the embryo grows, as well as moisture exchange between the embryo and the air in the incubator itself.
Evaporation is the process by which water changes from a liquid to a gas. Moisture moves from an area of ​​higher concentration, such as the contents of an egg, to an area of ​​lower concentration, the surrounding air. Higher temperatures increase the rate at which evaporation occurs. So the relatively high temperatures in the incubator are an ideal place for evaporation to occur. This is why maintaining humidity at the proper level during incubation is crucial, no matter what type of incubator you use.
The volume of water lost in the egg is replaced by evaporation with air. When the humidity is too high, the egg cannot leave enough water. This results in a small air cell (the air pocket at the large end of the egg). When the chick begins to hatch, it burrows, or “bursts internally” through the membranes surrounding it into that air cell, and takes its first real breath there. If the air cell is too small, the chick often cannot pass internally and cannot complete the hatching process. If the humidity is too low and the egg leaves too much moisture, an air cell that is too large may result, and the chicks are weak and attached to the shell. These chicks often do not survive hatching, and even if they do, they often die soon after.
Keep the eggs clean
When the egg is laid, a protective cuticle is formed around it. Immediately after application, the skin is damp, and if it comes into contact with dirt or other contaminants while it is still wet, these contaminants can be drawn into the egg. Therefore, keeping the nest box clean is extremely important when you know you are going to be incubating and hatching the eggs. Collect the eggs frequently to give less chances of damage to the egg, and to reduce exposure to bacteria and dirt.
Gently wipe the eggs if they are a bit dirty. Do not immerse it in water or soak it, but use a damp sponge or cloth. Remember that if you wash the eggs, you also wash their protective outer shell, which makes the shell more permeable. Use water that is warmer than the egg. If the egg is warmer, it tends to shrink because the water cools it which can cause contaminants to enter through the shell.
Use a solution designed specifically for washing eggs, and then be sure to follow the instructions exactly. Using a highly concentrated solution can infect embryos if the solution is drawn into the egg.
Forced air and constant air incubators
There are two basic types of incubators, forced air and still air. Either one can result in a successful hatch, as long as care is taken to ensure that the temperature and humidity are consistent. Both are very similar in function and design, except that the forced air incubator has a fan that circulates air over the eggs. For best success, set your forced-air incubator’s thermostat to 99.5°F and 60% RH. The fan will make sure that the temperature and humidity are consistent throughout the unit.
A still air incubator can be more difficult to manage temperature and humidity, but before the invention of electronic circuits and the small fans that come with a new incubator, countless eggs were successfully hatched in a still air incubator. Set the air incubator temperature to 100-101 degrees Fahrenheit at the peak of the eggs. It will apply air, or apply in a stationary air incubator, so where the reading is taken is important. Set humidity slightly higher, 60 to 65% relative humidity during incubation. Check the static air incubator often, the eggs can overheat more easily in the static air incubator. Fortunately, eggs can handle some variation from the ideal temperature, and tolerate a slight drop in temperature better than overheating for more than a few minutes, but the more constant environment you can provide, the better the hatching rate.
Hatching begins in the egg
The hatching process is considered one of the finest miracles in the animal world. During the last days of incubation, the chick grows to fill the entire egg, except for the air cell, which is the air pocket at the large end of the egg. At this time, the chick begins to orient itself in the shell and prepare for hatching. Their head and beak are folded under one wing, with their beak facing the air cell. Around day 19 of the 21-day incubation period, the chick’s head will turn forward, breaking the membrane separating it from the aircell, a process called “endotubing”. The chick takes its first real breath.
Clicking and pressing
By the 20th day, their lungs are working and the chicks have begun the dangerous part of the hatching process. Using an egg tooth, which is a small bump at the end of their beak, they will begin to tap the shell thousands of times. The shell becomes thinner at this stage, as the chick absorbs some of the calcium from the shell in forming its skeleton, and this “oozing” occurs fairly quickly.
Once the chick has pecked through the shell, it will rest for several hours, as its lungs adjust to breathing in the outside air. Proper humidity in the hatching is crucial at this stage; If the membranes dry out and stick to the chick’s body, it will be difficult for the young bird to leave its shell. During the second molting stage, the chick moves inside the egg, coils clockwise in a circle, and flicks away at the shell until a circumferential break in the shell, known as a “cloud”, is created. Then, the chick will emerge from the shell, only to fall disoriented and exhausted on the hatching floor.
You will see the newly born chicks sleeping deeply for several minutes, then moving around a bit, and then sleeping more as they gain strength and flexibility. But it doesn’t take long for them to start moving more as their muscles gain strength and coordination. In successful hatching, 95% of the eggs hatch within 24 hours. Wait to move the chicks to the brooder until they are dry and fluffy, otherwise they could get cold while moving.
Watch and wait
If you have multiple chicks that don’t hatch, the problem is likely to be caused by a moisture problem, either during incubation or hatching. The humidity should be around 50% during incubation and closer to 65-75% during the hatching process. Keep in mind that too much moisture is also not good. Pay attention to the manufacturer’s recommendations for their unit, and realize that you may have to do some gated to get a real feel for your incubator.
While it is tempting to try to help a chick that seems to be struggling during the hatching process, you can often do more harm than good. The entire process may take up to 24 hours. Attempting to speed things up by removing the shell and tearing the membranes can speed up the drying of the membranes, making it more difficult for the chick or damaging the feathers and delicate skin of the chick. Depending on the stage of hatching, the membranes may still be filled with blood that has not been drawn into the chick along with the yolk. Membrane rupture and rupture of the blood vessels will almost always result in the death or seriously weakened chick.
Non-slip incubator floors
The hatching ground is also important. Many newer incubators have hard plastic bases. These are great because they are able to clean and mop well between holes, but they are often too slippery for the chicks to get in. If the chicks have to struggle a lot to be able to stand on their feet, there is a good chance they will become legged. This means that their legs are spread out underneath and if left that way for too long you could permanently damage their legs. Cut a piece of cheap rubber shelf liner to fit the hatch floor. This material is readily available and can be washed and reused for many openings. Some Styrofoam brooders have thin wire floors, which will also serve to give the new chicks much needed traction.
Once the chicks are dry and fluffed up, it’s time to move them to a brooder. A good brooder should provide protection from drafts and be small enough so that the chicks do not stray too far from the heat source and become chilled, but not too small to prevent them from moving away from the heat source if they so choose.
Non-slip floors are also important in a brooder. Many people use sawdust with good results, but depending on the size of the brood, a rubber liner can work well, too. Whatever you choose, make sure it’s easy to clean. After the first three or four days, once the chicks start eating well, it’s amazing how much poop they can produce.
Move to the brooder
The brooder temperature should be near 95 degrees Fahrenheit for the first week, and can drop about five degrees each week thereafter, until the chicks are used to the room temperature, or are fully feathered enough to handle the outdoors.
Traditionally, the heat source for an incubator was limited to a heat lamp. These work well as a heat source, and can be raised or lowered to adjust the temperature in the brooder, but take care to prevent them from getting too hot for the chicks. It may take some trial and error to get the right temperature. The longer the heat lamp is lit on the brooder floor, the more heat it can build up. An important downside to heating lamp bulbs is the risk of fire. If the stand breaks and the bulb falls into the brood, it doesn’t take long for things to melt or catch fire.
A great alternative to heat lamps are chick brooder heat panels. This heat is radiated to the chicks and its height can be adjusted to adjust the temperature. The chicks will huddle at the bottom as if they were being brooded by a hen. They can cost a little more than a heat lamp, but properly cared for they can last for years, and they’re not likely to overheat or ignite something. These little mothers are available from many poultry supplying companies, and they come in a variety of sizes.
Watching newly hatched chicks grow and join your flock is one of the joys of raising poultry. These tips can help you get a great start in successfully hatching your chickens.