Extension’s embryology classes successful

By Tom Hintgen (Contact) | The Daily Journal

Published Saturday, June 7, 2008

One important mission of the University of Minnesota Extension in Otter Tail County is the educational outreach arm. A highly successful program the past six years has been the embryology program for area fourth-graders.

“As in prior years, students in this area gained an understanding of the egg, hatching of chicks, incubators and other areas of the poultry industry,” said Tammy Nordick, Extension educator, during a report to the Otter Tail County Board of Commissioners.

Nordick again worked with fourth-grade students and teachers in Fergus Falls, Underwood, Battle Lake, Pelican Rapids and Rothsay.

“We start the end of March and go until the end of May,” Nordick said. “I’m in each school four times (once a week for four weeks) and I go into

the fourth grade in all schools. The kids work on worksheets.”

The youngsters learn several things about the 21-day chick lifecycle. They also perform experiments such as combining calcium with eggs shells.

The fourth-graders learn that acid actually eats away at the shell.

“Candling eggs is something the kids also enjoy,” Nordick said. “We talk with the students a lot about the poultry industry, and that most of what we eat includes eggs.”

Students learn that chicks actually develop with their heads toward the large, flat end of the egg. An egg shell may have as many as 17,000 tiny pores over its surface. The average laying hen lays 257 eggs a year.

The chicken egg starts as an egg yolk inside a hen. A yolk (called an oocyte at this point) is produced by the hen's ovary in a process called ovulation. In fertilization, the yolk is released into the oviduct (a long, spiraling tube in the hen's reproductive system), where it can be fertilized internally (inside the hen) by a sperm.

The egg white is called the albumin. The eggshell is deposited around the egg in the lower part of the oviduct of the hen. The shell is made of calcite, a crystalline form of calcium carbonate.

The embryo develops inside the egg for 21 days (the incubation period), until a chick pecks its way out of its eggshell and is hatched.

The embryology program for area fourth graders is part of the Extension mission to involve people in improving the quality of life and enhancing the economy and the environment through education, applied research, and the resources of the University of Minnesota.

“This has been a very rewarding program the past six years,” Nordick told county commissioners.