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  • Cornell Atkinson
  • Animal Science
  • Animals
  • Climate Change

Michael L. Thonney, professor in the Department of Animal Science and director of graduate studies in the field of animal science, died April 23 in Ithaca. He was 71.

Over a Cornell career that spanned more than 45 years, Thonney made numerous contributions to animal science and agriculture through research that enhanced year-round sheep production systems and nutrition of highly productive sheep.

He combined these efforts with innovative extension and teaching programs, most recently creating a new course focused on dairy sheep management.

“Mike was incredibly dedicated to his students and a popular teacher – he was often approached for help by struggling students, and he supported them greatly,” said Tom Overton, chair and professor of animal science.

A headshot of Michael Thonney
Michael L. Thonney

Thonney was born on June 2, 1949 in eastern Washington state, where he was raised on a farm with a small flock of Hampshire sheep. He earned his bachelor’s degree in animal science in 1971 from Washington State University, and completed a master’s degree in 1973 and a Ph.D. in 1975 – both in nutrition from the University of Minnesota.

Thonney joined the College of Agriculture and Life Sciences in 1975 as an assistant professor of animal science. He was promoted to associate professor in 1981 and to full professor 1988. In 1998, he became the director of the Cornell Sheep Program, and he served as the director of graduate studies in the field of animal science since 2013.

One of his early research interests was quantifying the skeletal and muscular body composition of sheep and cattle as they grew and matured. Later work included investigating which genes and DNA markers play a key role in aseasonal breeding and milk production. He also looked at the role of vaccinating ewes in protecting their lambs from enterotoxemia type D, or overeating disease – common in livestock production systems with high-grain diets.

His most recent research and extension projects involved optimizing feeding and management practices for both milking sheep and grazing sheep. In overseeing the Cornell flock, Thonney developed research, extension and teaching programs that promoted better nutrition, health, selection, management and marketing strategies for highly productive sheep systems. He was deeply committed to the viability of small livestock farms.

“He reinvented the Cornell Sheep Program by establishing a sheep dairy and by creating many cross-disciplinary research and management projects – with wide-ranging impact for animal health, land management and sustainability.”

With funding from the Cornell Atkinson Center for Sustainability in 2018, Thonney launched a novel project at the university’s Musgrave Research Farm solar site in Aurora, New York, to determine the efficacy of using sheep to control vegetation growth and protect the panels from shading. Through collaboration with Johannes Lehmann, the Liberty Hyde Bailey Professor of Soil Biogeochemistry, and Scott McArt, assistant professor of entomology, the ongoing experiment – now being conducted at Cornell’s Cascadilla Solar Farm – will also evaluate how sheep grazing on solar sites influences pollinator habitat and the sequestration of soil carbon.

Thonney was deeply committed to graduate students in the field of animal science and was recently re-elected to a third term as director of graduate studies.

“Mike was a strong advocate for nontraditional applicants to the graduate field of animal science, taking the time to listen to their motivation and willing to go beyond the usual metrics most of us consider,” said Yves Boisclair, professor of animal science.

The Department of Animal Science will host a memorial event for students, staff and faculty on a date to be determined and in accordance with Cornell COVID-19 guidelines.

Thonney is survived by his daughter Elizabeth Thonney and son Benjamin Thonney. Arrangements are being made by Bangs Funeral Home in Ithaca. Memorial contributions to support the development of a scholarship in Thonney’s name can be made online here; please note that the gift is in memory of Mike Thonney.

Jana Wiegand is the editorial content manager for the College of Agriculture and Life Sciences.

This article also appeared in the Cornell Chronicle.

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