The Remarkable Ruminant
Author: Katy Wright, Arizona Beef Council
(Lesson shortened by TeachKyAg)
Grade Levels: 6 - 8
Purpose : In this lesson, students will follow the farm to fork process of producing beef, learn how cattle and other ruminants convert grass into nutrient-rich foods such as milk and meat, discover ways cattle recycle food waste, and identify careers in the beef cattle industry.
Estimated Time: 2 hours
Materials Needed
Interest Approach
Energy Chain image to display
Activity 1
Example rangeland images to display
A Cow's Digestive System video
Remarkable Ruminant handout, 1 per student
Activity 2
Food Waste Scenarios printout, 1 copy per class
Finding Value in Food Waste printout, 1 copy per class
Activity 3
Blank sheet of paper, 1 per student
Background Information
The Remarkable Ruminant (Printable for Student)
Cattle Digestion
Along with animals such as goats, sheep, buffalo, deer, elk, giraffes, and camels, cattle have a four compartment stomach. The function of these four compartments allow cattle to physically and chemically digest food that cannot be utilized by humans or animals that only have a simple stomach with one compartment (monogastrics).
The ruminant digestive system of cattle helps us use feed resources that would otherwise be discarded as waste. These waste products are known as byproducts or incidental products created by the manufacture of something else. An example is a potato peel. French fries are consumed regularly across our country. What happens to all the potato peels? The Ore-Ida French Fry processing plants in Oregon and Idaho send their potato peels to be consumed by cattle in feedlots. The cattle eat the potato peels and convert a waste product into beef, a food rich in zinc, iron, and protein. In summary, humans cannot digest most what cattle eat. They turn something of little value to humans (like grass) into highly nutritious beef.
When properly managed, cattle can also improve the quality and health of the rangelands where they live and graze. Typically, rangelands are located in areas that are too rocky, steep, or otherwise inefficient for growing human food crops. Keeping this land in grass prevents soil erosion. Cattle also provide natural fertilizer for the land in the form of manure.
Vocabulary Terms
byproduct: an incidental or secondary product made in the manufacture or synthesis of something else
calf: the name for baby cattle
feedlot: a type of farm operation where cattle are fed balanced feed rations in preparation for harvesting
forage: bulky food such as grass or hay typically consumed by livestock
heifer: female bovine that has not produced a calf
rangeland: open country used for grazing or hunting animals
ruminant: an animal with a four-compartment stomach
steer: male bovine that has been castrated
Education Content Standards
Career & Technical Education Animal Systems Career Pathway
AS.01.02 Assess and select animal production methods for use in animal systems based upon their effectiveness and impacts.
AS.01.03 Analyze and apply laws and sustainable practices to animal agriculture from a global perspective.
AS.02.01 Demonstrate management techniques that ensure animal welfare.
AS.08.02 Evaluate the effects of environmental conditions on animals and create plans to ensure favorable environments for animals.
NGGS Standards
MS-ESS3: Earth and Human Activity
MS-ESS3-3 Apply scientific principles to design a method for monitoring and minimizing a human impact on the environment.
MS-LS2 Ecosystems: Interactions, Energy, and Dynamics
MS-LS2-1 Analyze and interpret data to provide evidence for the effects of resource availability on organisms and populations of organisms in an ecosystem.
MS-LS2-2 Construct an explanation that predicts patterns of interactions among organisms across multiple ecosystems.
Companion Resources
Interest Approach - Engagement
Ask students, "Can you name something that can convert grass into nutrient-rich foods that we eat?"
After students have time to think and offer answers, display the following image and add sunlight to the equation. "Energy comes from the sun and produces grass. Humans cannot digest and gain essential nutrition from grass. What can convert grass into foods like meat, milk, and other dairy products?"
The answer is livestock. Specifically, animals like sheep, goats, and cattle that have a unique digestive system allowing them to break down the cellulose in plants. Today they will be learning about the digestive system of cattle and other ways cattle recycle and conserve resources while producing nutrient-rich food.
Procedures
Activity 1: The Remarkable Ruminant
Ask students, "How many people currently live on the earth?" Accept an answer of approximately 7 billion or go to the World Population Clock for a more precise answer. Follow up by asking students if the world population is expected to increase or decrease in coming years. (increase)
Conclude with students that it is, and will become, increasingly important to use our land wisely to provide homes, food, space, and resources for a growing population.
Ask, "Can we use ALL of our open space to grow crops for food?" Display the following images for illustration.
4. Ask students:
Is some land too dry or too wet for crop growth?
Is some soil too rocky or sandy to grow crops?
Could steep inclines or cold climates prohibit a farmer from growing crops successfully?
5. Ask students to think back to what they have learned so far. Could the land that is unsuitable for crop farming be used by cattle (or sheep) to produce food? (Yes!) Tell students that this is possible due to a unique digestive system. Show the video clip, A Cow's Digestive System (1:35 mins).
6. Distribute the Remarkable Ruminant handout to students. Instruct students to read the article on page 1 and highlight each example they find of ways cattle convert otherwise unusable resources into useable resources. Students will then complete pages 2 and 3 of the worksheet.
Activity 2: How Cattle Recycle
Preparation: Prior to class, print 1 copy of the attached Food Waste Scenarios. Cut scenarios into individual strips and save until you reach step three. Print 1 copy of the attached Finding Value in Food Waste and cut into eight individual strips. Distribute the slips around the room before students arrive. You can leave them visible or hide under chairs, tape to the walls, etc.
Ask students to brainstorm all of the places where food goes to waste. Students will likely think of uneaten food at their home, school cafeteria, or restaurants. Once students have exhausted their own ideas, provide a prompt. Ask, "When you are preparing food at home is there any portion of the food that you throw away?" Provide examples such as:
Do you ever peel a fruit or vegetable and throw away the peel?
Do you ever throw away the core of an apple or the rind of a watermelon?
Do you always eat the heel/crust of a loaf of bread?
Point out that on a house-by-house basis, the amount of food waste may be relatively small (though potentially impactful). Ask students to think about the waste from a large food processing facility. Ask, "Are there food processing facilities that could produce truckloads of waste?"
Divide the class into eight groups. Give each group one Food Waste Scenario slip. Allow groups to read and discuss their assigned scenario and come up with a potential solution.
Next, introduce the concept of cattle being able to digest food and receive nutritional value from foods that humans either do not choose to eat or cannot eat because it provides little/no nutritional value to our bodies.
Inform students that they will find strips of paper around the room that contain the nutritional value of the food product represented in their scenarios. Instruct students to search for the papers to find the information they need to determine if the food waste from their scenario could be used in another way.
Once students have found the slip of paper to match their scenario, have them come up with another solution for the food waste based upon what they learn. Have each group share their scenario and solution with the class.
After each group has shared with the class, use the following questions for reflection:
What is the definition of a byproduct?
An incidental or secondary product made in the manufacture of something else. To learn about additional feeds from byproducts, see the Enriching Activity below titled, "Digging Deeper into Byproduct Feeds."What limitations can farmers/ranchers face in feeding their cattle byproduct feeds?"
Some byproduct feeds have geographic limitations. For example, citrus fruits are only grown in a few states. To further discuss the geography of these byproducts, see the Enriching Activity below titled, "Mapping Out Commodities and Byproducts."What makes cattle different from humans and allows them to digest food waste products like the ones we discussed today?
Cattle are ruminants which means they have for compartments in their “stomach” allowing them to break down and digest plant products that other animals and humans cannot.So what? Why does this matter or why is this important?
The world population is growing exponentially which places a greater demand than ever before for food. Using alternative food sources that would otherwise go to waste, and feeding them to ruminants like cattle, allows farmers to efficiently and economically produce food for this growing population.
Concept Elaboration and Evaluation
After conducting these activities, review and summarize the following key concepts:
Cattle have a unique ruminant digestive system allowing them to gain energy from food such as grass, hay, and other forages that are of no nutritional value to humans.
Cattle provide beef (hamburger, steak, roasts) and dairy products to our diet as well as many byproducts such as leather, medicines, etc.
Cattle can utilize land that is too dry, rocky, wet, or steep for crop production. Well managed grazing practices promote healthy rangelands.
Cattle can eat food processing byproducts rather than sending the waste to landfills.
Enriching Activities
Have students watch the TedTalk, How to Fight Desertification and Reverse Climate Change
Digging Deeper into Byproduct Cattle Feeds: In Activity 2, students learned about eight byproducts that can be fed to cattle. There are many more examples. Assign students to research other common cattle feeds that are otherwise waste if not used as livestock feed. Possible feeds include:
barley or hops hulls
cereal by-products
citrus pulp
culled vegetables
cotton seed husks
grasses
molasses
soy hulls
sugar beet pulp
Grape Peels
Corn Gluten
Corn Stalks
Have students read the Huffington Post article, Farm Animals Actually Eat People's Leftovers - And It's Good For the Planet. If desired, use a KWL chart to increase engagement. Discuss student findings.
Mapping Out Commodities and ByProducts: To help students understand the geographic limitations of using byproducts for feed, distribute the attached Mapping Out Commodities and Byproducts activity sheet to each student. Have students research where the list of food products are commonly grown in the United States. The U.S. Department of Agriculture National Agricultural Statistics Service and the Interactive Map Project are two helpful websites that can be used or students may conduct their own internet search. Students may research products individually, work in groups, or do a special report on just one product.
If time allows, encourage students to explore the maps to find out what food products or waste products are local to your state and may be fed to cattle.
Note that bakery waste will likely not be listed. Instruct students to think of a local grocery story or bakery and have them think about what the store does with bakery items that are not sold. This is considered bakery waste and stores either need to dispose of it in the trash or have farmers pick it up.
If students research the entire list, they will need to use both websites to find the food commodities.
For a useful handout comparing the monogastric and ruminant digestive systems, see pages 6-7 of A Stomach At Work, created by Michigan State University Extension. For a lab activity demonstrating how the monogastric stomach works, see pages 1-4.