Net reductions in greenhouse gas emissions from feed additive use in California dairy cattle

PLoS One. 2020 Sep 18;15(9):e0234289. doi: 10.1371/journal.pone.0234289. eCollection 2020.


The livestock industry is one of the main contributors to greenhouse gas emissions and there is an increasing demand for the industry to reduce its carbon footprint. Several studies have shown that feed additives 3-nitroxypropanol and nitrate to be effective in reducing enteric methane emissions. The objective of this study was to estimate the net mitigating effect of using 3-nitroxypropanol and nitrate on total greenhouse gas emissions in California dairy industry. A life cycle assessment approach was used to conduct a cradle-to-farm gate environmental impact analysis based on dairy production system in California. Emissions associated with crop production, feed additive production, enteric methane, farm management, and manure storage were calculated and expressed as kg CO2 equivalents (CO2e) per kg of energy corrected milk. The total greenhouse gas emissions from baseline, 3-nitroxypropanol and nitrate offered during lactation were 1.12, 0.993, and 1.08 kg CO2e/kg energy corrected milk, respectively. The average net reduction rates for 3-nitroxypropanol and nitrate were 11.7% and 3.95%, respectively. In both cases, using the feed additives on the whole herd slightly improved overall carbon footprint reduction compared to limiting its use during lactation phase. Although both 3-nitroxypropanol and nitrate had effects on decreasing the total greenhouse gas emission, the former was much more effective with no known safety issues in reducing the carbon footprint of dairy production in California.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animal Feed*
  • Animals
  • California
  • Carbon Dioxide / metabolism
  • Carbon Footprint / statistics & numerical data
  • Cattle / metabolism
  • Dairying / methods*
  • Dairying / statistics & numerical data
  • Female
  • Food Additives / administration & dosage*
  • Food Additives / adverse effects
  • Greenhouse Effect / prevention & control*
  • Greenhouse Effect / statistics & numerical data
  • Greenhouse Gases / adverse effects
  • Greenhouse Gases / metabolism*
  • Lactation / metabolism
  • Nitrates / administration & dosage
  • Nitrates / adverse effects
  • Propanols / administration & dosage
  • Propanols / adverse effects


  • 3-nitrooxypropanol
  • Food Additives
  • Greenhouse Gases
  • Nitrates
  • Propanols
  • Carbon Dioxide

Grants and funding

EK and XF received award from California Air Resources Board ( under award number 17RD018 and USDA NIFA ( under award number NC2040. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.