About 25 children from the Onondaga Nation School got a taste of how milk goes from cow to carton in a tour of Cornell's Dairy Plant, July 24. The experience was both hands-on and hands-in, as students were encouraged to stick their arms into Cornell's fistulated Holstein, Rose, to investigate the cow's fiber digestion.

The students, ranging from third to seventh grades, spent the day on campus as part of a summer program at the Onondaga Nation School in LaFayette, N.Y.

"About seven years ago, we decided to start a [weekly] after-school science program [at the Onondaga Nation School]," said Carl Batt, Cornell professor of food science, who organized the event. "Because it's an after-school environment, we're trying to get the kids engaged and interested and try not to make it too much of a content-driven experience. They are there mainly to have fun."

Batt has been visiting the Onondaga Nation School and community for about seven years, ever since he met them at the New York State Fair, where they perform cultural dances.

During an interactive lesson on ruminant digestion and how it differs from other mammals, Debbie Cherney, associate professor of food science, explained how the opening in the cow's side goes into the animal's rumen, the largest of four compartments in a cow's stomach. The rumen digests hearty grass material through a fermentation process and is home to an assorted microbe population, Cherney said.

"When you put your arm in there, it squeezes. So when you move around, it lets go, and when you pull it out, it squeezes again," said Shane Daniels, a rising seventh-grader at the Onondaga Nation School. Cherney explained that the muscles of the rumen contract in a circular motion to move the ingested grasses as they are broken down.

Meranda Pierce, also a seventh-grader, was apprehensive at first to stick her arm inside Rose, but learned that the environment was warm and soft, not "gross."

At the Cornell Dairy Plant, the students learned where Cornell receives its milk, how the milk is pasteurized and homogenized, and how the milk is packaged and shipped. The program ended on a sweet note with free Cornell Dairy Bar ice cream for all.

Laura Janka '09 is a writer intern at the Cornell Chronicle.