The CEO of Minneapolis-based Techne Corp. has resigned from the bio-tech company after disagreeing with the company's choice to succeed him.

Thomas Oland, 71, told the Techne board in a letter disclosed Monday that he's decided to retire after 27 years with the company. Oland is resigning effective Nov. 30. He also had been board chairman, but resigned from that post and from the board itself on Nov. 1.

Gregory Melsen, the chief financial officer, was named interim CEO pending a search for a permanent replacement.

Oland leaves while disagreeing with the board on the future leadership of the company. While the board of directors named Melsen as interim CEO, Oland made it known to the board via e-mail he would like Melsen to have the job full-time and objects to a search outside the company for a new CEO.

"I disagree with the board's decision to recruit an individual from outside our company as its new CEO," Oland wrote. "In my opinion, a much better choice is to promote from within. Specifically, I recommend Greg Melsen as your new CEO."

Oland added, "Since I do not agree with your decision to hire someone from outside as CEO, I will not participate in the recruiting process and I cannot endorse or support your position with either our employees or shareholders."

Robert Baumgartner, a nine-year board member, was named board chairman.

In its most recent fiscal year, the life sciences company earned $112.3 million on revenue of $314.6 million.

Staff writer Patrick Kennedy contributed this story.

Steve Alexander • 612-673-4553