He was born on a 120-acre Jersey dairy farm in Cleveland in southern Manitowoc County and obtained a Bachelors degree in Dairy Science from UW-Madison in 1970. Between two stints with the Peace Corps in Kenya and Paraguay, Otto worked for his father on the farm and did odd jobs off the farm. In the 1980s, after obtaining a Masters in African Studies from Ohio University, he operated the farm for six years, expanding from 28 to 45 cows.

In 1988, Otto left the farm to work on a Masters and PhD in Dairy Science Nutrition at UW-Madison, finishing in 1995. He did his field work in Ethiopia where he fed tree leaves to sheep. He then worked for Agri-Management, a dairy placement company in Madison, the African Development Bank in Ivory Coast, and New Age Computers in his hometown before his five years at Dairy Strategies in Madison with part-time teaching at Northeast Technical College in Green Bay. Otto also did short-term international work with Dairy Strategies in Costa Rica and Holland, and with the Babcock Institute in Cyprus.