Sarah Yvon Russell, Finn Schaeffer, Katie Davis

TEACHER GUIDE

Why do cows burp so much?

This unit is an introduction to cattle digestion and offers a comparative view of human and cattle physiology with a focus on a topic middle schoolers find interesting. Cattle burps are related to microbial activity, which is a good foundation for cell activity and very basic microbiology. It is also a good integration of animal science material with ‘big picture’ issues, as it ties something students already know is important (global warming) to something they’ve likely never thought about (cattle and their digestion).

Grade Level:

Students should be in middle school, grades 6-8. Students should have a basic understanding of how food is used in digestion– simply, that food is turned into nutrients and processed by the body for energy.

Learning Objectives:

Students should learn that cows digest things differently than humans do, and that a big part of this is their unique foregut anatomy and the microbes that help them break down their food. They should also be aware that gas is a big byproduct of this digestion process, and that this digestive gas has a bigger impact on the world around them. They should be able to connect individual learning objectives to create a “big picture” diagram of a cow.

Lesson Format:

It is group work, where students will watch learning videos together and then brainstorm together in a way that helps them think through the learning objectives. They will then complete a final integrative learning activity where they trace the passage of food and gas through a cow’s foregut.

Lesson Assessment:

Students will trace food’s path as it goes through the cow’s stomachs, paying special attention to how gas is produced. In particular, they should include a depiction of how microbes are involved– a drawing of a microbe intaking food and sending out gas would be sufficient. Microbes should be depicted as existing in the rumen, not in any other compartment, and gas should be shown tracing a path back out the mouth.

Resources

Students will need access to a partner for discussing ideas during brainstorming, a copy of the above image, and potentially a whiteboard to note ideas.

Estimated Duration

This will be a lesson that ideally should be able to be completed in an average 45-55 minute class period but can be adjusted to fit longer or shorter lesson times by eliminating some of the discussion questions or expanding them to include the optional activities.

Outline

Instructors will first go over the basic anatomy of a cow, including a quick summary of the foregut (rumen, reticulum, omasum, and abomasum). The instructor will then discuss microbes and their function in cattle digestion plus how they contribute to gas production. Finally, these topics will be linked by explaining why cows expel gas from the mouth rather than anus and how cattle burping contributes to global warming.

Common Misconceptions and Challenge Points

• Students may have difficulty conceptualizing the way the rumen functions
• Students may not grasp the different quadrants of the foregut
• Small and large intestinal function are not the main point of this lesson, but may be mentioned in passing to help students gather where colonic gas comes from and why cows don’t produce it

Lesson Material:

Why Do Cows Burp So Much_

Knowledge Assessment:

https://create.kahoot.it/share/cow-questions/2b403079-09f8-47de-8c59-36a574cdd839