Two top executives of General Mills — Chief Financial Officer Don Mulligan and Blue Buffalo chief Billy Bishop — are leaving, the company announced Tuesday.

Kofi Bruce, the company’s corporate controller, will be promoted to chief financial officer to succeed Mulligan, who will retire in June, ending 21 years with General Mills.

Bishop — who joined the company as president of pet foods when General Mills acquired Blue Buffalo last year — will step down from the role on Oct. 1. He will remain with the company through the end of the year before stepping into an advisory role, providing input on branding, marketing and innovation for Blue Buffalo. Bishop, his brother and father, who started Blue Buffalo together, will work from the pet-food brand’s Wilton, Conn., main office.

The two moves will have a cascading effect on other executive roles at Golden Valley-based company. Bethany Quam, who has been with the company since 1993 and is currently president of General Mills’ Europe and Australia segment, has been appointed president of the pet segment, effective Oct. 1. She will lead Blue Buffalo from its Connecticut office.

Dana McNabb, president of U.S. cereal and a 20-year General Mills veteran, has been appointed head of Europe and Australia, beginning Jan. 1.

“I’m proud of the depth and diversity of General Mills’ leadership talent, which is reflected in the quality of the people transitioning to and from our senior leadership team,” Jeff Harmening, General Mills chief executive, said in a statement.

He said the changes were carefully planned. In the financial post, for instance, the handover will happen in stages.

Bruce will become vice president of financial operations on Sept. 1 and then take over CFO responsibilities next February. At that time, Mulligan will move into an advisory role until retirement. Mulligan has led the company’s financial operations for the past 12 years.

“Don has been an incredible asset to General Mills for more than 20 years. During his tenure as CFO, General Mills generated a 185% increase in value to our shareholders,” Harmening said. “Don was instrumental in this performance by helping craft plans that balanced long-term growth and profitability and initiatives that actively transformed our portfolio.”

Bruce, 49, joined General Mills a decade ago following financial-leadership roles at Ford Motor Co. and Ecolab. At General Mills, he has served as treasurer, vice president of finance for U.S. yogurt, vice president of finance for food service and global revenue development. He saved operating costs, lowered financing costs and grew profits in food service, the company said.