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Incubating eggs can be tricky for beginners. You need to maintain very specific conditions to ensure the highest hatch rates for your eggs, and the window of appropriate temperatures is fairly small.
A temperature that is too cold, or especially one that is too hot, can significantly affect the number of eggs that hatch. In this article, we’ll examine the perfect temperature to keep your eggs at, what can happen if the temperature gets too hot or too cold, and what you can do to ensure a high hatch rate.
Conditions for Incubating a Chicken Egg
The optimal conditions for incubating and hatching chicken eggs involve maintaining specific temperature and humidity levels. Here’s a summary of the optimal conditions:
- Incubation Temperature: The ideal temperature for incubating chicken eggs is around 37.5 to 37.8 degrees Celsius (99.5 to 100 degrees Fahrenheit). This temperature range is crucial for proper embryo development.
- Hatching Temperature: As the eggs approach the hatching stage (typically the last three days of incubation), some sources recommend slightly lowering the temperature to about 37.2 degrees Celsius (99 degrees Fahrenheit) to help with the hatching process. However, maintaining the initial temperature range is also common practice.
- Incubator Temperature for General Use: For a general-use incubator setting without specifying the stage of egg development, maintaining a temperature of around 37.5 degrees Celsius (99.5 degrees Fahrenheit) is advisable.
- Incubator Temperature and Humidity for Chicken Eggs: Alongside temperature, humidity plays a vital role in the incubation process. The recommended humidity levels are:
Maintaining these conditions is essential for achieving a high hatch rate. It’s also important to ensure that your incubator is well-ventilated and that the temperature and humidity are evenly distributed throughout the incubator. Regularly turning the eggs until the last three days before hatching is also crucial for proper development.
Condition | Temperature (Celsius) | Humidity | Stage of Development |
---|---|---|---|
Incubation Temperature | 37.5 to 37.8 | N/A | Day 1 to Day 18 |
Hatching Temperature (last 3 days) | 37.2 (optional adjustment) | N/A | Day 19 to Day 21 (Hatching) |
General Incubator Temperature | 37.5 | N/A | Throughout incubation |
Incubator Humidity | |||
First 18 Days | N/A | 40-50% RH | Day 1 to Day 18 |
Last 3 Days (Lockdown Period) | N/A | 65-70% RH | Day 19 to Day 21 (Hatching) |
RH: Relative Humidity.
Temperature Adjustments: Some sources suggest slightly lowering the temperature during the last three days to aid in hatching, but maintaining the initial range is also common.
Humidity Measurements: Humidity levels are critical, with increased humidity required during the “lockdown” period to facilitate the hatching process.
Ventilation and Egg Turning: Ensure the incubator is well-ventilated and turn the eggs regularly until 3 days before they are due to hatch.
Best Temperature and Humidity Levels for Chicken Egg Incubation
When hatching chicken eggs, there is a very small window for ideal temperature and humidity. That window changes slightly throughout the entire incubation period, which is generally about three weeks or 21 days.
Your incubator’s temperature should be about 99 degrees Fahrenheit to 102 degrees Fahrenheit or 37 degrees Celsius to 39 degrees Celsius.
Depending, of course, on the unit of temperature your thermometer uses. This temperature should be kept consistently, aiming for an average of 100 degrees Fahrenheit or 38 degrees Celsius for about 18 days.
After 18 days, the temperature should be slightly lowered to around 98.5 degrees Fahrenheit or just below 37 degrees Celsius.
The lowered temperature makes up for the increased heat that comes from the egg embryos before hatching.
Aiming for higher temperature levels is never a good idea to get your chicks to hatch faster. Patience is required, and you need to allow the natural cycle to do its thing. Otherwise, you’ll be in for a higher mortality rate when your eggs hatch.
Always aim for the middle of the road in the temperature window, and keep careful track of the temperature in case of any errors or fluctuations. Also, ensure your incubator is kept in an area without extreme temperature fluctuations. External temperature fluctuations can greatly affect the sustainability of the temperature in your incubator.
Direct sunlight is a no-go, so you should keep your incubator in a shady environment with a stable temperature.
For 18 days, you should generally aim to keep the humidity level between 50% and 55%. After 18 days, you’ll raise the humidity level to about 65% while slightly lowering the temperature. This increased humidity level keeps the chicks from getting stuck on the egg membrane as they’re beginning to hatch.
Humidity can be adjusted by simply placing a container of water below the egg tray and decreasing and increasing the ventilation until the desired humidity range is reached. Many incubators also include trays where water can be added to increase humidity.
How Do I Adjust The Temperature On My Incubator?
Your incubator’s temperature should be controlled by a thermostat, which often consists of a screw that will be turned either counter-clockwise to increase heat or clockwise to decrease heat. The incubator’s control mechanisms can vary, though, so be sure to check your instruction manual. Many more modern incubators will use digital controls that make temperature adjustment much easier.
It is important that you set up the incubator and set the temperature a few days before you are going to place your eggs. This will allow you to ensure that the temperature is stable and adjust for any fluctuations. Once you’ve got the eggs in, be sure to check the temperature and humidity levels several times a day to ensure that everything is as it should be.
However, allow a two-day window after first placing the eggs, during which you don’t increase the temperature. The eggs need to stabilize with the temperature of the incubator, and this can make temperature reading difficult in the first 48 hours. If you’ve properly stabilized the temperature beforehand, things should even out between the eggs and the incubator after a day or two.
Overcompensating and increasing the temperature immediately after placing the eggs can result in the temperature getting too high right out of the gate, which will kill your eggs on arrival.
Over time, the temperature can increase as the heat coming from the eggs increases due to the growing embryos, so you’ll need to keep a careful eye to ensure that it never goes above 102 degrees Fahrenheit or 39 degrees Celsius. Even just a few hours in a temperature that is too cold or too hot can affect the overall mortality rate of your eggs.
What Temperature Is Fatal for Chicken Eggs?
High temperatures are much more detrimental to the health of your eggs than cold temperatures, so you should be much more careful about keeping the temperature from getting high than you would be about keeping the temperature from getting cold.
A temperature of 103 degrees Fahrenheit or just over 39 degrees Celsius for just a few hours can drastically increase the mortality rate of your eggs. Likewise, a temperature even higher than that for even just a fraction of an hour may make it so that only one or two of your eggs hatch, if any.
How Hot Is Too Hot for Chicken Eggs?
If chicken eggs get too hot, it need to be immediately rectified. Otherwise, they likely won’t hatch. As we said in the prior section, a temperature just slightly higher than is allowed in the appropriate temperature window can result in serious problems after only an hour or two.
Temperatures that greatly exceed 102 degrees Fahrenheit can do even more damage in a shorter time. Be sure to keep a constant eye on the temperature of your incubator and never allow it to go over 102 degrees Fahrenheit or even really get that close to it.
If you’ve discovered that your eggs have been sitting at over 102 degrees Fahrenheit for any time, you should immediately attempt to cool them down by taking them out of the incubator and placing them in cool water. If you don’t have a container big enough, you can spray them with a hose. You’ll want to cool the eggs so the shells are about 80 degrees Fahrenheit or 27 degrees Celsius.
The shells will get cooler faster than the embryos, so aim low. Don’t worry about over-cooling, as lower temperatures are not nearly as detrimental as the higher ones.
While cooling off the eggs after they’ve been sitting in higher temperatures isn’t a miracle fix, it’s the best you can do given the situation. The hatch rate will likely have been affected slightly, but you’ll still have made it better than it would have been without cooling them down. If you are curious, you can candle your eggs to see if there is any movement inside and also to check for veins.
Candling eggs simply entails illuminating the inside by placing the egg on a powerful light source that makes the shell see-through. If the embryo has died, there will be no movement, and the veins will generally disintegrate.
Otherwise, put your eggs back in the incubator and hope for the best outcome during hatching time. Be sure to monitor the temperature multiple times a day!
Will Eggs Still Hatch If They Get Cold?
Eggs can typically hatch after being in colder temperatures for short periods, but it might still affect the hatch rate slightly. A few hours in colder, and sometimes even freezing, temperatures can often have little to no effect on the mortality rate so long as the problem is resolved soon enough.
Because of this, you shouldn’t be too worried if your incubator gets unplugged or turned off accidentally for only an hour or two. Just plug it back in or turn it back on; everything should stabilize.
Cold temperatures pose the biggest issue to your eggs if they crack from freezing. Your egg won’t hatch if it’s cracked. If your eggs have been in very cold temperatures, it is ideal to let them sit at room temperature for about a day before placing them back in the incubator, as you don’t want any extreme temperature fluctuations messing with the integrity of the egg.
How Long Can Incubated Eggs Be Cold?
Just a few hours is the safest bet for how long incubated eggs can be in colder temperatures, although the less time, the better. There can be situations where several more hours can be added to that window with little to no effect on the hatch rate; it all depends on how cold the temperature is and how far the eggs are.
As we said, finding out that your incubator has turned off for a few hours in not too extreme of a low temperature isn’t that big of a deal. A small period at a lower temperature likely won’t affect the hatch rate. However, it’s always best to play it safe and routinely check the incubator’s temperature.
Power outages can also be an issue, as in some cases, they can last for more than a couple of hours. Hooking up your incubator to a backup generator is a good solution for this.