Sustainability & efficiency

Validation study for methane breeding values with GreenFeed methane recordings on commercial Dutch dairy farms

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Abstract

Methane (CH4) emissions have been identified as a major contributor to global warming. Reducing enteric CH4 emissions through genetic selection is a promising long-term strategy. In line with this, CRV publishes CH­4 breeding values (BV) for Holstein dairy cattle in the Netherlands since April 2025. These BV are derived from large-scale sniffer measurements and on a smaller scale also GreenFeed (C-lock inc.) measurements. For a good adoption of the CH4 BV by farmers, it is important to prove that cows with high BV for CH4 really emit less CH4. Therefore, a validation study is currently being carried out to evaluate the relationship between published BV and actual CH4 emissions measured under commercial conditions (September 2025-June 2026). The study will be conducted on, in total, 15 commercial farms, each equipped with a GreenFeed system for six weeks. The protocol includes one week for installation, two weeks for cow adaptation, two weeks for actual data collection, and one week for deinstallation and cleaning. These 15 farms were previously equipped with a sniffer in their milking robot, so the cows have own performance records for CH4 emissions. Currently, preliminary data on six farms were collected, this data had not yet been finalized by C-Lock. For three of the six farms, at least 10% to 33% of measurements within the data collection period require post-processing adjustments due to insufficient airflow. These farms were therefore excluded from the present analysis, resulting in a final dataset comprising three farms (54 cows). On each farm, a maximum of 50 cows were identified based on (1) reliability of their CH4 BV (ranging from 32% to 51%), and (2) availability during the measurement period. Data was filtered to include only cows with at least 20 valid CH4 measurements, each lasting at least two minutes, which were averaged per cow over the two-week period. Correlations between the two-week averages and the published CH4 BV were calculated per farm. The average CH4 BV of the included cows was 99 (92-106), and the two-week average CH4 emission was 387 (214-533) g/d. The Pearson correlations between the average CH4 emissions and the published CH4 BV ranged from -0.27 to -0.45. This shows that on a farm cows with a high CH4 BV indeed emit less CH4 than cows with a low CH4 BV. These results will hopefully improve the acceptance and adoption of the CH4 BV (and the mitigation index) by farmers. When farmers actively select cows based on the CH4 BV, genetic selection becomes an effective mitigation strategy to reduce the environmental footprint of livestock, as it is cost-effective, permanent and cumulative over generations. Until June 2026 data on more farms will be collected and analyzed.

Keywords: 2026

How to Cite:

de Haas, Y., Gredler-Grandl, B., Koning, L., Snijder, J., Van Gemert, C. & Veerkamp, R., (2026) “Validation study for methane breeding values with GreenFeed methane recordings on commercial Dutch dairy farms”, World Congress on Genetics Applied to Livestock Production Digital Archive 2026(1): 2285425. doi: https://doi.org/10.31274/wcgalp.23697

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