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The Mystery Ration (Grades 9-12)

Rickreall Dairy is located just 15 minutes from Oregon’s state capitol, Salem. Our tour guide is the farm’s owner, Louie Kazemier. Rickreall Dairy is home to 3,500 Holstein cows. The cows are milked three times a day and produce an average of 10 gallons of milk per cow per day. Rickreall Dairy is inspected once a month, and works with 18 different government agencies. Milk is filtered and chilled before being tested to be sure it’s always free of antibiotics. You can find Rickreall Dairy’s milk in the Willamette Valley under the Darigold and Fred Meyer brands.

The Mystery Ration

Discover the nutrient requirements of dairy cows! Students will collaborate in teams to unlock feed examples through a series of escape boxes. As students work to unlock each escape box, they will be tasked with calculating rations using the Pearson Square method to provide a balanced meal for dairy cows to enjoy!

Activity 1: Watch the Rickreall Dairy Virtual Farm Field Trip
Watch the virtual field trip on our website called Rickreall Dairy – The Scoop on Cow Nutrition. This tour will provide students with background knowledge of a dairy cow’s diet and how this relates directly to their production of milk and capability of producing a wholesome nutritious product that we can enjoy!


Activity 2: Introduction to Pearson Squares
Explain to students that today we will be acting as a dairy farmer and determining the amount of different feeds to include in our cow’s ration based on the desired rate of nutrients. Using the example provided on the worksheet show students how to calculate rations using the Pearson Square method.

Activity 3: The Escape Box Ration Challenge!

Students will work through a series of escape boxes unlocking locks by calculating different feed rations as described on cards in each box.

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