Simple Chicken Egg Hatching Guide
This guide is based upon the use of a modern incubator using micro-computer technology, and one that can accurately achieve the settings you have entered. Using properly stored eggs from healthy stock you should be able to achieve a hatch rate average in excess of 80%.
Days 1 – 3
Set the incubator temperature to 38.00 C, and the humidity setting to 70%RH. If your incubator will allow it you can increase this further to as much as 75/78%RH. Allow several hours before loading with room temperature eggs. Check that the trays in the incubator are in turning mode and the water supply is connected
Days 4 – 7
Reduce the humidity setting to 67%RH. Leave the temperature at 38.00 C. Check the water level is OK
Days 8 - 11
Reduce the temperature setting to 37.70 C. Leave the humidity setting at 67%RH. If your incubator has a cooling facility, set it to operate for 45 minutes cooling per day. If it does not have a cooling facility, then once per day, turn the power to the machine off and open the incubator door slightly for a period of 20 minutes, then close door and turn power back on. (Set an Alarm to remind yourself) Again, check the water level.
Days 12 – 17
Reduce the temperature setting to 37.60 C. Leave the humidity setting at 67%RH. Again, be sure to check the water level. Continue cooling operation once per day. Open air vents slightly to increase oxygen and decrease carbon dioxide whilst maintaining humidity and temperature settings.
Days 18 – 19
Cease cooling operation.
Level the turning trays and switch off the turning mechanism. Remove the eggs from the egg trays and transfer them to the hatching baskets. Reduce the temperature setting to 37.50 C. Increase the humidity setting to 70%RH. Open air vents a little more to further increase oxygen and decrease carbon dioxide and maintain humidity and temperature settings.
Days 20 – 21
Increase the humidity setting to 72% RH. If your incubator will allow it you can increase this to as much as 75/82%RH.
Keep the temperature setting at 37.50 C. Air vents as open as possible but maintain humidity and temperature settings.
Do not open the door during the final 2 days, wait until all chicks have hatched, even if it takes longer than the 21 days.
If you are using a cycle system with different age batches of eggs at the same time, a constant temperature of 37.60 C and humidity 65/68% RH is the best compromise for chicken eggs.
© David Campbell Heka Incubators UK Ltd