“Is it worthwhile to try and match your genetics to the environment?” asked Dr. Jared Decker, Wurdack Chair of Animal Genomics, University of Missouri, to launch his presentation during the Beef Improvement Federation (BIF) Symposium in Knoxville, Tennessee, on June 11.
According to Decker environmental stressors, like fescue toxicosis, cost the beef industry approximately $1 billion a year. Decker shared information regarding a study conducted in the 1960s that moved cows from the Brookfield Research Station in Florida to the research station in Miles City, Montana, and cows from Montana to the station in Florida. Pregnancy rates for the cows in Florida from Montana were 55%. In comparison, to the Hereford cows native to Florida, this was 28% lower making a strong case for genetics by environment (G x E) interactions. Reproduction is one of the most impacted traits by G x E interactions. Body condition and metabolism are the other two most impacted traits.
Decker went on to introduce BIF Symposium participants to three USDA-funded projects that are underway to study the impact of, and best ways to, address G x E interactions. In multiple studies from the first project, genes tagged by G x E interactions and local adaptation selection had functions affecting blood vessel constriction/dilation. This is an important indicator of fescue toxicity, altitude stress, and thermotolerance. Additional genes associated with G x E effects were involved in immune response and metabolism. These functions affect the animal’s ability to adapt to their environment and deal with multiple stressors.
“Adaptability is defined as an animal’s ability to appropriately sense and respond to the environment,” Decker said. “If you are describing your cattle as ‘adaptable’ without actually measuring their ability to sense and respond to environmental stressors you’re just telling us stories.”
The latter two projects that Decker described are designed to develop tools to help producers measure and match genetics to their environment more effectively than just buying animals from similar environments. EPDs and crossbreeding are both approaches that Decker recommends to address G x E interactions.
“We have the technology now to measure traits that are greatly impacted by environment and generate genetic evaluations for these traits,” he said.
Some examples that Decker talked about include genetic evaluations for fertility (defined more robustly than heifer pregnancy as a binary trait), pulmonary arterial pressure (PAP), which occurs in environments of high altitude, and hair shedding which can address thermoregulation and sensing changing seasons.
“Hair shedding is an economically relevant trait, and I challenge anyone who doesn’t think so to come mend fence with me while wearing their winter parka,” Decker explained.
He tied addressing G x E interactions with biological rules like Bergmann’s rule and Surface law. He suggested leveraging new technologies like 3D imaging to measure surface area for truer genetic evaluations of metabolism than body weight. To watch Decker’s full presentation, visit https://youtu.be/I5-6tR-XzJg. For more information about this year’s Symposium and the Beef Improvement Federation, including additional presentations and award winners, visit BIFSymposium.com.
