The fitness and nutrition coach also played "Tequila" by The Champs with some help from a neighbor.
Collectively, the videos have been viewed more than 12 million times on Twitter.
Herrmann told KGW he's played the sax for his family and his dog, but got the idea to perform for the cows when he spoke to his wife.
“I was telling her I saw this video of people playing with animals and I wonder if it’ll work,” he said. “She said let’s do it.”
Herrmann, his daughter and wife traveled to a field where cows were grazing and Rick Herrmann started his performance.
"I thought they might be curious," he told KGW. "I guess I didn't expect them to crowd the fence so much."
"It just seemed to resonate with so many people, so many people said they had a hard day and they watched it and it put a smile on their face," Rick Herrmann told KPTV.