Instructor Callie Unruh and her bovine assistant Tiny visited Hillsboro Elementary School Monday morning with their mobile dairy classroom to show students where milk comes from and demonstrate how milk travels from a cow’s udder to a milk jug.
“Tiny is just over 2 years old; that’s 24 years old in human years,” Unruh told students. “That means she ages the equivalent of one human year every month. At the age of 2, she had her very first calf. Mammals like Tiny have to have a baby first before they can start producing milk.”
Tiny is a 550-lb. jersey cow, which according to Unruh is currently the second most popular breed of dairy cow on the market. The most popular breed are 2,000 lb. Holsteins that are generally much too big to fit in the mobile dairy classroom Unruh and Tiny travel from school to school in.
“Tiny makes six times the amount of milk her baby calf needs in a day,” Unruh said. “We feed her calf two bottles a day so she doesn’t overeat.”
To make milk, cows like Tiny eat food like hay, grass, silage, and cottonseed, as well as other items like peanut shells, potato chips, and candy bars that people don’t normally think about as cow feed, Unruh said.
“Some farmers that live near candy factories buy the castoff candy bars and mix them with the herd’s food to help add protein to what they consume,” she said. “Tiny eats about 60 lbs. of food a day and drinks the equivalent of a bathtub full of water.”
Milk is generally 87 percent water, Unruh said.
However, Tiny stays thin because her body burns a massive amount of calories as she produces milk.
Milk production is largely dependent upon a cow’s size, Unruh said. Tiny produces about 6 to 8 gallons a day.
In order for Tiny to produce milk successfully, she not only needs to be fed and watered adequately but she also needs to be in a secure and accommodating environment.
Dairy farmers supply cows with shelter from the elements to help increase milk production.
“The better we take care of them, the better they take care of us,” Unruh said. “Forty degrees is the ideal weather for a jersey cow to produce milk.”
Unruh said cows have one udder that is split into four-quarter sections.
She demonstrated the standard milking process by which the udder is sterilized with iodine before connecting a “milking claw”.
The milking claw is a suction device that mechanically removes milk from a cow’s udder.
“The milk you drink never touches human hands,” she said. “The milking claw is cleaner and more efficient than milking by hand. Milk isn’t wasted from kicked over buckets and germs cannot contaminate the milk as easily.”
As the milk passed from Tiny’s udder to a tank in the mobile classroom, Unruh told students that its temperature was about 101.5 degrees, the same as Tiny’s normal body temperature.
On the farm, cows are milked in “milking parlors” in after which the equipment, structure, and cows are all cleaned.
“The milk is then cooled to about 38 degrees until it is sent to the processing plant,” she said. “Milk straight from the udder only lasts about three days, but it can last up to two weeks after it is homogenized and pasteurized.”
Unruh told students that raw milk normally has about 4 percent fat content. To create 1 percent, 2 percent, and skim milk, the according percent is removed.
“Milk straight from the cow generally has a sweeter and richer taste than homogenized milk,” she told students.
Students also learned that they are supposed to consume about three servings of dairy a day because milk has nine vitamins and minerals, including calcium, that benefits a growing body.