Part of Unit: Animal Inheritance and Selection Principles
Lesson Plan Overview / Details
The selection of the herd bull is one of the most important decisions the cattle breeder makes. A major advancement in the improvement of the beef industry has been the development of sire summaries. Sire summaries provide information on traits that are economically important to cattle producers. Each calf produced receives one-half of its genetic makeup from its sire, so we will learn how to use EPD's to select traits that are desirable and economically profitable based on real life ranch scenarios.
- One class period
- 55 Minutes
California Career and Technical Education Standards
- ANR.D.D5.1 Evaluate a group of animals for desired qualities and discern among them for bre...
- ANR.D.D5.2 Understand how to use animal performance data in the selection and management of...
- ANR.FS.11.0 Demonstration and Application
- ANR.FS.5.1 Apply appropriate problem-solving strategies and critical thinking skills to wor...
- ANR.FS.5.2 Understand the universal, systematic problem-solving model that incorporates inp...
- ANR.FS.5.3 Use critical thinking skills to make informed decisions and solve problems.
- ANR.FS.9.3 Understand how to organize and structure work individually and in teams for effe...
California Academic Content Standards (Reinforced)
- ELA.8.R.VCD.1.3 Use word meanings within the appropriate context and show ability to verify thos...5
- ELA.9-10.LS.C.1.1 Formulate judgments about the ideas under discussion and support those judgments...
- ELA.9-10.R.CAGT.2.5 Extend ideas presented in primary or secondary sources through original analysis...3
Objectives and Goals
- Be able to read and interpret a ranch scenario and understand how EPD's apply to terminal sire selection.
- Evaluate a group of animals for desired qualities and discern among them for breeding selection.
- Understand how to use animal performance data in the selection and management of production animals.
- Apply appropriate problem-solving strategies and critical thinking skills to work-related issues and tasks.
Activities in this Lesson
- Who's your sugar daddy? - Hooks / Set
1.Students enter the class room and are immediately given (written on the board or in handout form) a scenario making them the proud owners of 10 Angus cows.
2.The cows are all first calf heifers (build the ranch scenario to fit your area) and the new owners (students) are shopping for the best buy in semen (or a bull).
3.On the overhead are 4 bulls (first slide of the ppt for EPD's) they must visually appraise and place in order (rank) of preference.
4.In groups of 2-3 they then turn to each other and compare rankings and discuss why they agree or disagree with each other. (1 min)
5.You ask the question - which bull is your sugar daddy? Which bull will cross the best with your new cow herd? (the class of bulls will have an obvious winner and three other bulls that are fairly close in phenotype)
6. Most students will be anxious to offer the first bull as the winner and choice to purchase.
- bull class.ppt [ Download ] A slide with four bulls to judge in ppt
- What are EPD's? - Lecture
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.
- Data for Existing Class of 4 Bulls [ Download ]
Each bull the students observed on the overhead (screen) now have performance numbers and as a teacher - the time has come to review what each number means in relation to the actual value (review the vocabulary list).
After each set of data has been discussed go back to the slide with the pictures of the bulls and have the class decide which bull they absolutely could not use on first calf heifers.
The discussion should include the importance of having as high of calving percent as possible and the first and easiest way to accomplish that goal is to use bulls with low birth weights. Detail the importance of high numbers when evaluating cattle and their EPD numbers, except for birth weight. Using a bull with a heavy birth weight may correlate and help get to that bigger end point, yearling weight, but if the bull's calves are born dead, there will be no economic gain.
The answer should jump out at them that the bull they placed/ranked first as the best visually appraised (phenotype) bull is not the bull to be used on their first calf heifers.
The next part of understanding EPD's is to use the
- Assessment Types:
Based on the following data of Angus Performance Bulls, determine which bull you would select from the paper to use on the following scenerio : upon completion have the students turn in their results with a brief explanation as to which bull they would chose and why.
These bulls are being selected for use on yearling heifers. Female progeny will be retained as replacements and steer progeny marketed either at weaning or fed and sold at harvest at the end of the feeding phase.
No. Herd No. Birth Date BW WW YW Milk
No. 1 904 2-25-09 +0.5 +42 +74 +16
No. 2 907 2-28-09 +3.5 +43 +80 +16
No. 3 909 3-03-09 +1 +55 +97 +22
No. 4 911 3-03-09 +3.1 +45 +82 +21
Breed average EPD +2.1 +45 +82 +21