Overview of CSU AgNext Research Using GreenFeed to Assess Gas Flux from Beef Cattle


Dr. Sara Place

Associate Professor of Feedlot Systems - AgNext

Colorado State University

Building the evidence base for low-methane cattle isn’t about one breakthrough measurement — it’s about 2,100 animals, sixteen experiments, and the methodological discipline to know exactly what each number means.

Presentation Overview

What Three Years and 2,100 Animals Reveal About Measuring Methane Correctly.

Dr. Place gave the symposium a detailed account of what CSU AgNext has built since standing up its climate-smart research facility in late 2022: six identically configured pens, each with five SmartFeed units and a GreenFeed, running up to 300 animals at a time. In just over three years the program has run sixteen experiments and accumulated records on more than 2,100 individual cattle — plus two trailer-mounted GreenFeed units measuring grazing animals out on Wyoming rangeland. It’s one of the most controlled, highest-throughput gas-flux operations anywhere, purpose-built to answer the methodological questions the rest of the field is still asking.

Chief among those: how many visits does it take to get a trustworthy methane phenotype? Pooling animals with 100+ visits as a gold standard and walking the correlations backward, her team landed on a working answer of about 55 visits to hit a 0.95 correlation — a number they’ve since reproduced across multiple datasets. They also found that traits like CO₂ converge even faster, opening the door to using gas flux to predict feed intake in grazing or group-housed cattle where measuring intake directly is nearly impossible.

“Good science requires good data – and good data requires careful, consistent, real world measurement”

Two findings landed hardest. First, the variation is real and large: within a single contemporary group — same ranch, same diet, same management — animals consistently differ by 30% or more in methane output, confirming there is genuine signal to select on. Second, that signal is environment-dependent. Following animals from forage to finishing, her team saw 35% to 83% of cattle re-rank depending on how methane was expressed and whether they were implanted — a caution that a single measurement in one production phase may not predict the next. And when Dr. Vargas tested 448 finishing steers against 72 published prediction equations, even the best model tracked observed emissions only loosely — a direct argument for why this measurement work has to continue.

Reference Material

View Slide Deck

place-clock-symposium-2026.pdf

CSU AgNext: Using GreenFeed to Assess Gas Flux from Beef Cattle

Exclusive Interview

Dr. Sara Place On Why Real-World Measurements Are Better Measurements.

In this exclusive interview recorded after her sessions, Dr. Place discusses what large-scale, commercially relevant measurement has taught CSU AgNext, why methane ranking shift across production phases, and how gas-flux data could one day estimate feed intake in animals that cant be individually fed. 

SM

Interviewed by Sarah Mikesell

Senior Editor · The Cattle Site

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