Hatching Eggs in the Classroom:

Set Stage

The “set stage” refers to the first 19 days of incubation in chickens. Chicken eggs hatch in 21 days. Incubating different species in the same incubator at the same time is not recommended, because other species hatch at different times.

Birds in the wild frequently turn their eggs in the nest. Turning eggs during incubation prevents embryo death and unhealthy hatches.

Hand-turning eggs interests students and builds anticipation. Eggs must be turned at least three times every day; five times is even better. This turning schedule must be maintained even over the weekend. For this reason, an automatic turner is recommended, since many school districts restrict access to classrooms on weekends. If your incubator is equipped with an automatic turner, the eggs will be turned every hour.

To turn eggs by hand, rotate the egg 180 degrees so that the X and the O alternately face up at each turn. Emphasize that students should wash their hands before touching the eggs. Eggs can become contaminated with germs during incubation, and dirt and oils can block the pores of the egg. Remember that the large end of the egg should always be higher than the small end. Also, remember to quickly replace the incubator lid so that the temperature inside will remain constant.

Ventilation, Temperature, and Humidity of the Incubator

The chick embryo uses oxygen and gives off carbon dioxide. The impact of this gas exchange is small during the early period of incubation or when a small number of eggs are incubated. However, follow the recommendations of the incubator manufacturer to ensure that adequate oxygen is available to the developing chicks.

The temperature in the incubator should be 99.5o F.

If the temperature fluctuates more than 0.5o from 99.5o, a poor hatch is likely. Check the temperature at least twice a day.

Relative humidity should be set at 86o F wetbulb temperature. Humidity should not fluctuate more than 1 or 2 wet-bulb degrees.

Relative humidity, which measures the amount of moisture in the air, is extremely important in the process of egg incubation. To maintain humidity, every incubator must have a source of moisture. The easiest way to provide this moisture is to put a shallow pan of water in the bottom of the incubator. Add water to the water pan (or trough) every day to ensure proper maintenance of humidity.

It is easy to make an instrument to measure the humidity inside the incubator. To do this, you need a normal thermometer, a 6-inch piece of shoelace, and a short piece of dental floss. First, slip the bulb end of the thermometer about 1 inch into the open end of the shoelace. Next, tie the dental floss around both the shoelace and the thermometer directly above the bulb. This will keep the shoelace from sliding off. Then place the opposite end of the shoelace directly in the pan of water. The reading on the thermometer will now be your wetbulb temperature (see figure). The temperature reading of the wet bulb will be less than that of a dry thermometer because of evaporation. The wet-bulb reading is used as an index of relative humidity.

To increase the humidity, add a second pan of water. To decrease the humidity, use a smaller pan. If the incubator temperature is correct, the only factor governing humidity is the surface area of water inside the incubator.

A wet-bulb thermometer is easily made using a dry thermometer. The wet bulb registers a lower temperature than the dry bulb because evaporation cools the thermometer. The wet-bulb reading is an index of relative humidity.

Next Back

Hatching Eggs

Set Stage

Ventilation, Temperature, and Humidity of the Incubator

Egg Incubators and Egg Incubator Resources

Indian Ringneck Resources

Electus Parrot Resources

Sun Conure Resources

Finches Resources

A Teacher's Guide

Incubating Eggs

Helpful Resources