Part of Lesson Plan: Expected Progeny Difference (EPD)

Activity Overview / Details

1.You pose the question "what is the most important trait used in selecting a herd bull?" How do you know that the first bull is really your sugar daddy? Are looks everything? Or is there more to selection that meets the eye?

2. Allow students to spend 3 minutes discussing in their group what they believe are the most important traits.

3. Ask for answers, and they will vary from size, muscle, soundness, and eventually lead them to birth weight (birth size).

4. Pose another question, "how can size, muscle, reproductive soundness, and birth weight be measured other than using your eyeball? How can we determine the history and traits of the bull's family, his dam and sire? How can we make sure the bull we buy fits our needs on our ranch?

5. Bring up a slide with the data from each bull on the screen and introduce the concept of Expected Progeny Difference. Include a hand out of the class of bull's EPD numbers so the students can refer to the numbers while reading the scenario to the students so they get familiar with the needs of a ranch for a group of cattle.