Sheep Industry News August 2025

Our journey with Sheep GEMS is nearing its end

Dr Ron Lewis Emeritus Professor, Univer sity of Nebraska-Lincoln T ime flies. Over nearly four years I have had the pleasure of working with talented

sheep scientists and students, and with nearly forty Katahdin, Polypay, Rambouillet, and Suffolk producers engaged in the National Sheep Improve

ment Program (NSIP)—our so-called Innovation Flocks—in Sheep GEMS. With this project nearing its finish this December, it seemed timely to share what we have learned so far. In this article, I summa rize team members’ insights into the project based on questions that I posed to them.

“Historically, we think of genetics as being the way to identify parentage or carriers of various problems that have plagued the industry. While these have value for our industry, the power comes from identifying individual and flock genetic diversity.” Tom believes as we become more and more accurate in the predic tion of various genetic traits in our breeding programs, we will con tinue to see greater productivity and profitability through improved breeding and selection decisions every generation. When asked if he found anything surprising, Tom responded, “It is valuable to stand back and see the changes in crop production, and other livestock species from genetics. The only thing surprising to me is that we have not moved faster to identify and adopt the new technology that will bring the quantum leaps in productivity in the U.S. sheep industry. Some ‘What if’ questions are helpful. What if our entire flock had the productivity of our very best ewe? What if we could wean a 175% lamb crop of 120 or even 130 lb. lambs on grass? What if every ewe had a great udder with ideal teat placement that did not require having jeans with manure-stained knees from kneeling to start lambs nursing? What if every ram could increase loin eye size, improve lamb eating experience, while producing replacement ewes that can raise a set of twins. What if we could ‘stack traits?’ Such ques tions are all within reach through the power of genetics!” Dr Luiz Brito is an Associate Professor of Animal Science at Purdue University, specializing in quantitative genetics and genomics. I spoke with Luiz about one of the traits we are considering, ewe longevity. Figure 2. Measurements collected in Sheep GEMS either in all flocks (*) or only in flocks located at USDA Agricultural Research Service facilities

Figure 1

As a reminder, the “GEMS” in Sheep GEMS stands for Genetics, Environment, Management, and Society. Our aim was to consider how these four key facets of a sheep production system collectively im pact robustness and resilience to weather conditions or, more general ly, fitness of your flocks. We measured a lot of fitness traits, such as ewe longevity, gastrointestinal parasitism, udder health, and lamb survival, in both Innovation and USDA Agricultural Research Service (ARS) flocks. Such measures help us describe Genetics. The flocks engaged in Sheep GEMS are spread across the U.S., with unique geographies and weather conditions, or Environments. We also conducted a national survey to gather information about on-farm practices, learning about your Management and, to a smaller extent, Society. Tom Boyer, a third-generation rancher and a Board Member of Sheep Genetics USA, serves as the Chair of our project’s industry advisory board. I asked Tom what aspects of the project stood out as most key to him. “The broad array of production traits encompassed in the study has been interesting to learn about and see the deep dives that become ap parent as we wrap our minds around the power of genetics.”

“Ewe productive longevity basically means how long a ewe stays

28 • Sheep Industry News • sheepusa.org