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Animal Feed Lesson Plan: See, Touch and Do
Animal Feed: See, Touch, and Do
A Hands-On Lesson Plan on the Basics of
Animal Feed and Animal Nutrition
1. To describe the role of an animal nutritionist.
2. To discuss why it’s important to feed animals a balanced and nutritious diet.
3. To discuss and describe the feed milling process.
1. To recognize animal nutritionist as a possible career path for an individual interested in animals.
2. To describe the importance of animal feed processing and mixing.
3. To explain feed/ingredient sorting and the effects of particle size and shape on feed mixing.
1. Items needed to complete activities (make sure to have enough supplies for all students to participate either in small groups or as individuals):
- Cereal (several kinds, but a minimum of three)
- Fine sand, rocks, and marbles
- Containers with lids that hold more than 4 cups (one per group)
- Plastic cups (two per group)
- Plastic sandwich bags
2. Consider asking students to bring an assortment of animal feed, such as samples they may have at home (cat, dog, horse, bird, or rabbit food). All of these create wonderful starting points for discussions about animal feed and feed manufacturing.
3. Additional items nice to have on hand for the activities:
- Whole corn kernels
- Ground corn (several sizes if possible)*
- Whole soybeans
- Soybean meal*
- Animal nutritionist, formulating diets for pets, livestock, zoo animals and exotic pets, or fish
- Laboratory personnel, making sure the feed ingredients and finished feed are properly manufactured
- Feed mill operator/manager
- Nutrition salesperson, selling everything from specific feed ingredients to finished feed
- Animal nutrition consultant, as a private consultant or for a large feed company
- Researcher in animal nutrition or animal science
- Teacher (agriculture, animal nutrition, or animal science)
- A career at a drug company, in either sales or research*
- A career in a regulatory agency, such as the Food and Drug Administration (FDA)**
- Pure and wholesome;
- Produced under clean conditions;
- Free of harmful substances; and
- Labeled appropriately and truthfully.
This lesson explores the basic principles of preparing feed for pigs and chickens, although the concepts can be applied to many animals and expanded to include discussions around other animals and/or feed manufacturing topics. Both pigs and chickens are monogastric species and consume similar diets. The basic ingredients in pig and chicken diets are corn and soybeans (soybean meal). These ingredients are processed and manufactured to be similar in size (although not perfect).
- The nutrition within the corn kernel is better utilized (digested) by the animal if the kernel is ground.
- When whole ingredients are fed, pigs and chickens will pick out the ingredients they like best and eat those first (much like people picking out the M&Ms or chocolate chips in trail mix). Chickens have color preferences and will sort out the yellow whole corn to eat first. Pigs also sort out their favorite ingredients. Mixing appropriately-sized ground corn into the feed prevents this “feed sorting” and ensures that the pigs and chickens eat the correct amount of all ingredients in their feed.
- Ground corn helps produce high quality pellets. Whole corn or even course grinding of the corn does not produce high quality pelleted feed.
Activity 1: Particle Size
- Have the students break into groups of 3 or 4. Have several cereal varieties available. One way to get cereal variety is to ask each student to bring 1 cup of cereal from home. Make sure each student in the group has a different kind of cereal.
- Give the students a container to be the mixer. The container needs to have a lid and be able to hold more than 4 cups of cereal. Large yogurt containers with lids and jars with lids work well.
- Have each student in the group add 1 cup of cereal to the mixing container, for a total of 3 to 4 cups. Have one student act as the mixer by physically picking up and shaking the container for about 15 seconds.
- Once the cereals are mixed, have the students sort the cereals back into the original separate cereals, emphasizing that this is what animals do if allowed to pick and choose what they want to eat. The cereals are fairly easy to sort.
- Have the students take the same cereal and smash it into fine particles (easily done in a plastic sandwich bag with a fist or book). Once the cereal is smashed, have the students mix the cereals together again.
- Ask the students to again sort the cereals back into the original separate cereals. This sorting process is increasingly difficult when the cereals are of similar size. There still may be a few large pieces that the students can pick out, but overall, the cereals mix better and are more difficult to sort.
Fat or another liquid product is added to the feed. Added fat, which increases the moisture content, causes the feed to pack together. The packed feed has a hard time moving through the feeding system. When feed packs together, it stops flowing through the feeding system. The feed lines or feeders may need to be agitated to restart the flow.
Feed Handling Problems Typical Causes Feed ingredients are ground too fine (small).
What Happens When the ingredients are very small, the feed tends to pack together and has a hard time moving through the feeding system. End Result Possible “out of feed” occurrence. Example Think of an hourglass minute timer filled with sand that comes with some board games. When the timer is turned upside down, the sand runs from the top to the bottom of the hourglass in 1 minute. Sometimes, the sand packs together and gets stuck. The timer has to be shaken to restart the flow.
Fat or another liquid product is added to the feed.
Added fat, which increases the moisture content, causes the feed to pack together. The packed feed has a hard time moving through the feeding system.
When feed packs together, it stops flowing through the feeding system. The feed lines or feeders may need to be agitated to restart the flow.
Activity 2: Particle Size and Shape
- Have the students break into groups of 3 or 4. Provide each group with two plastic cups and enough fine sand and rocks (or marbles) to fill the cups. It doesn’t matter if you use sand and rocks or sand and marbles, as both combinations show that smaller sized ingredients (sand) are more likely to pack together, creating a feed handling issue.
- Have each group build a cup-shaped castle with the dry (as is) sand and another castle with the rocks or marbles. Discuss how the sandcastle holds shape better than the rock or marble castle.
- If the groups want to explore the effect of particle shape, have them make castles with rocks and also with marbles. The rocks and marbles should be similar in size. The rocks stack together better than the marbles, due to the irregularity in their shapes (not all rocks are the same shape). Because of the uniformly round shape of the marbles, they don’t pack together. Instead, they roll off each other.
The same principle applies to animal feed. The more uniform and round the ingredients, the less likely the feed will pack together. This decreases the chance of feed handling problems.
When making a feed that is fine (small) in particle size, it’s better for the feed to have a more uniform, round shape. The tendency of the small particles to pack together (like sand) is offset by their uniform, round shape which causes the particles to not pack together and roll off each other (like marbles). This balance between size and shape reduces feed handling problems.
- Have the students add a small amount of water to the cup of sand and the cup of rocks or marbles and then make castles again. The water makes the sandcastle hold together even better, while the rocks or marbles still roll off each other. The sand with water is a perfect example of what really fine grinding and added fat (moisture) will do in feed lines and feeders.
- Maximize animal health and performance;
- Prevent feed sorting; and
- Prevent feed handling problems.
- FDA 101: Animal Feed
- FDA’s Role in Animal Health – Yes! No! Maybe So! – What FDA Does and Does Not Regulate, FDA Veterinarian Newsletter, Issue 3, 2010
- Animal Food & Feeds
- Animal Feed Regulations