Cattle's Role in Feeding a
Hungry World
An Ag/Beef education program for use in elementary and middle school
classrooms. Brought to you by the Sandhills Cattle Association in
conjunction with area high school youth.
Written by Nancy Peterson, DVM
Sandhills Cattle Association
PO Box 786 • 130 South Hall Street • Valentine, Nebraska 69201-0786
Phone: 402-376-2310 • 1-800-658-0551 • Fax: 402-376-1881
E-mail: [email protected] • www.sandhillscattle.com
Cattle's Role in Feeding a Hungry World
Supplies Needed
 Paper doll chain (provided)
 Apple and knife to cut it
 Book "The Romance and Reality of Ranching" (provided)
 Samples of grass, hay, silage, shrubs, weeds and straw
 Copy the 11x17 diagram of the bovine digestive system included or use Slide #19 from "My Cheeseburger Came from
a Farm" Power Point presentation (provided)
 List of by-products cattle can eat (get from CD - "Wastes are Food Too" Word document)
 Dried cow pie
LESSON 1: Cattle play an important role in feeding a hungry world.
Object: A chain of paper dolls touching by outspread hands
In 1990, the world population was 3.4 billion people
In 2025 there will be 8.5 billion people in the world
How many people is that? (Move to a globe if there is one in the room)
If every person in the world made a chain by touching hands like these dolls, they would make a chain that was 4.8 million
miles long! That chain would go around the world 192 times.
How can the world feed that many people???
Object: Start with a whole apple and think of it as representing the earth.
1. Slice the apple into quarters and set three quarters aside. Three quarters of the world is covered by oceans.
Only one fourth of the world is land.
2. Slice the remaining quarter in half. Set one half aside. One eighth of the world is inhospitable to people
(polar ice caps, deserts, swamps, high mountainous areas) People can live in only one-eighth of the world
3. Slice the remaining section in four pieces and set three pieces aside.
Those three pieces represent land that is either too rocky, too wet, too cold, too steep or have too poor a soil to grow crops.
They also include land that could produce food but can't because it is buried under cities, highways, shopping centers and
other structures that people have built.
.
4. That leaves only 1/32nd slice of the world available to feed those 8.5 billion people.
A. Only 11% of that land can grow crops that people can eat!
B. The remaining agricultural land can only produce food by being harvested by grazing animals who can live on
the land that is unsuitable for growing crops.
Object: Book "The Romance and Reality of Ranching" Section: The Land p. 8-27
Show the students pictures of different environments and talk about how cows can live in different areas.
Did you know that 85% of all the plants that grow in the world can not be digested by humans?
Object: Pass out samples of grass, hay, silage, shrubs, weeds or straw Ask the children if they would like to eat them.
Many plants are very fibrous, containing lignin and cellulose that we can not digest. We would starve if that is all we had to
eat. Ruminants are animals that have four stomachs which allow them to break down plant materials into building blocks
that their bodies can use.
Cattle's Role in Feeding a Hungry World
LESSON 2: A Journey Through a Cow's Digestive System
Object: Copy the 11x17 diagram of the bovine digestive system included or use Slide #19 from "My Cheeseburger Came
from a Farm" Power Point presentation
1. Cattle have long tongues that help them to pull grass and hay into their mouths.
2. They have powerful molars in the sides of their jaws to begin crushing the leaves and stems. They produce gallons of saliva (spit)
that works to soften the forage.
3. When they swallow their food, it travels down their esophagus to the first stomach, called the reticulum, which acts like a
plumber's trap under the kitchen sink because it catches things a cow accidentally eats that are not digestible, like rocks, or wire or
metal.
4. Cows are recycling bits of food constantly because they swallow a mouthful of grass or hay and continuously belch up bits of
their food, which they rechew and mix with more saliva to make it softer and more broken down. This is called "chewing their
cud".
5. The second stomach is called the rumen and it is a much larger part of the same compartment as the reticulum. The rumen is
what makes ruminants able to digest plants that people can't eat.
A. The rumen is a huge compartment full of partially broken down forages, water, and saliva. A full
rumen can weigh up to 400 pounds in an adult cow.
B. What makes a rumen special is that it is actually home to millions of good bacteria and microorganisms
that have the ability to break down cellulose and lignin into substances that the animal can absorb in
the rest of its digestive tract. When we feed a cow hay, we are really feeding the "bugs" in her rumen.
The bugs then feed the cow. This is an example of symbiosis, a relationship between different
organisms that is beneficial to both.
6. Once food is ready to leave the rumen, it passes into the omasum, an organ about the size of a basketball. It is full of muscular
folds, like the pages in a book, which serve to squeeze excess water out of the food.
7. The food then passes into the last stomach called the abomasum, or true stomach, which works exactly like our own stomach,
where proteins are broken down into amino acids and carbohydrates into simple sugars.
8. These materials then pass into the small intestine to be absorbed into the blood stream.
9. The left-overs then go into the large intestine which absorbs much of the water. What is left passes out through the colon and
rectum to be deposited on the ground as a juicy cow pie. Cow manure is a rich fertilizer which plants can recycle and use again
(Have a dried cow pie in a baggie in the basket)
.
Cattle's Role in Feeding a Hungry World
LESSON 3: A Cow Is Like a Walking Recycling Center
Reference materials include: "Wastes are Food Too" and "Ruminants Recycle" Word documents on CD and "The Romance and
Reality of Ranching" book section The Ultimate Recycler p. 106-107. The trainers can choose which and how much to talk about
it.
1. Cattle eat 50% of all the by-products left over from processing fruits, vegetables and grains that would otherwise go to waste
and then have to be disposed of in over crowded dumps.
Show samples such as: stale bread, potato peels, apple peels, cornstalks, culled vegetables, rice, etc. (See list in "Wastes
are Food Too")
2. Cattle are part of a system of renewable resources.
A. Through photosynthesis, Plants convert energy from the sun into proteins, carbohydrates, vitamins, cellulose, and
lignin. They absorb minerals and nutrients from the soil and make them available for grazing animals.
B. Grazing animals harvest the plants and turn the indigestible plant parts into protein, energy, and minerals, like iron
and zinc, to feed a hungry world.
C. Animals pass the leftovers as manure, which is a rich fertilizer that makes the soil able to produce more plants.
D. Every season the plants grow again to start the cycle all over.
Show pictures from book that show the benefits of grazing p. 100-101.
Conclusion:
1. Grazing ruminants play an important role in feeding a hungry world. Without their help, much of the world's land would be
unable to feed our growing population.
2. Grazing ruminants play an important role in utilizing our renewable resources.
Thoughts.
This may be more involved than we want, but hopefully, it will be a resource that our trainers
can use as little of or as much of as they wish.
I think it would be possible to use it as a hand out. We could make a cross-word puzzle out of
the words found in bold (At least, I think I can make one!!!) as an activity to leave behind.
I have received a picture from Hawaii, but none from any other state organization that I emailed. Today, I e-mailed Beef Magazine, asking them if they had appropriate pictures in their
archives that they would
be willing to share with us.
Except for the two picture blocks, the "show and tell" items ought to be easy for the kids to
come up with. We would probably want to include a pattern for the paper dolls for the kids to
cut out.
As incredible as my "people chain" seems, I am pretty sure the math is right. I figured a 5 foot
arm span per person, multiplied that by 8.5 billion and divided that by 5,280 feet. The
circumference