By KAREN McDOUGALL The incredible egg. An incubator filled with fertilized eggs was the star of a three-week stay in an elementary school classroom when I was the 4-H program assistant. Why? One of the school enrichment programs is the chick embryology program, Hatching Future Scientists. Along with the fertilized eggs, there were many questions and much learning. When going into the classrooms, the students always asked how long it would take for the eggs to hatch. It takes about 21 days. To make this real for the students, a hatching book was created. Starting with day one, this book gave a day-by-day look at the development of the chick inside the egg. We talked about why the chickens laid colored eggs: white, brown, blue or green. How? The color of the chickens earlobes determined the egg color. Chickens with white earlobes lay white eggs. Chickens with red earlobes, the students would say lay red, but these are the ones who lay the brown, blue or green eggs. Most of our eggs were brown eggs and were specific breeds. We could tell if they were male or female by their color after they hatched. Have you ever noticed the white spot or germ spot on the egg yolk? This is where the chick will start to develop if the eggs are fertilized. When a hen sits on her eggs, her body heat incubates the eggs. She turns them with her beak, which is part of her maternal instincts. The average clutch a hen hatches is 12 eggs. The students asked where the developing chick got its food. Nutrition comes from the yolk. It was quite interesting to process. Our incubator had a turner, which would turn the eggs every 30 minutes. If the humidity or temperature is off, the development and hatching of the eggs is affected. Fertile eggs are set in the incubator on the first day in the classroom. Humidity and temperature controls are carefully monitored. Between 38 and 60 hours after the eggs begin to incubate, many things start happening inside the eggs. The heart is beating. The upper part of the embryos body turns on its side. The eyes, ears and brain take shape. On days four and five, wings and legs are growing and the chick is moving inside the egg. On day nine, the eyelids form and on day thirteen the eye closes. One highlight for the students is candling the eggs. This is done around day 10. What is candling? Shine a small light into the large end of the egg, darken the room and we are able to see inside the egg. Seeing nothing means the egg is not fertile. One sign of a developing chick is the blood vessels growing around the embryo. Many times a black dot is visible, which is the chicks eye. If conditions are right, the students are able to see the chick move inside the egg. During my second visit, we did eggsperiments. Spinning eggs indicated if we had a raw or hard-cooked egg. Eggs that float indicate whether they are spoiled or good to eat. The answers? Hard-cooked eggs spin faster. If the egg floats, throw it out. On day 18, the egg turner is unplugged so the chicks can get themselves ready to hatch. The chick makes a small hole in the egg shell, then pecks its way around the egg. When completed, the chick makes its appearance in the classroom. Once the chicks are dry, the teachers put them in a special container with food and water. The students are able to hold them and feel how soft and delicate they are. By the time I stopped to pick up the chicks, they were starting to have feathers on their little wings. What an egg-citing time that was! Students named their little friends. Many of the students wanted to take them home, but I always shared that I was taking them to a neighbor who would take care of them. It takes about 26 weeks for the pullets to start laying; since they are young hens, they will be laying the smaller eggs. Have you ever found a double yolk? While the hens are getting their bodies in sync with laying, you may find an extra bonus. Laying hens typically lay an egg roughly every 24-27 hours and produce 200 to 300 eggs per year. As the hen gets older, her eggs will get larger. It was an egg-cellent time for these students to see a miracle in their classroom, from an egg to a chick. McDougall is the SNAP-Ed program assistant at the OSU Extension of Hancock County.

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Weekend: Elementary school classroom gets 'egg-cited' - The Courier