Use of feed additives to reduce enteric methane emissions in dairy cattle: meta-analysis of data retrieved through a systematic review
Abstract
We conducted a meta-analysis of quantitative data extracted from selected peer-reviewed papers describing
in vivo
studies on enteric methane emissions from dairy cattle treated with feed additives, compared with a control group. The aim was to identify feed additives that significantly reduce enteric methane emissions, expressed as g/day, g/kg dry matter intake, g/kg milk produced, and g/kg energy-corrected milk. The feed additives considered were polyunsaturated fatty acids (PUFAs), 3-nitrooxypropanol (3-NOP), essential oils (EO), and monensin. Four electronic databases (PubMed, CAB Abstracts, Web of Science, and Scopus; 2001–2024) were used to retrieve papers, following the PRISMA 2020 statement.
Effect sizes were calculated as log response ratio percentages and analyzed using three-level random-effects models. Heterogeneity, cluster-robust variance estimation, and leave-one-out diagnostics were applied. A total of 34 studies met the inclusion criteria.
Of these, 19 investigated the impact of PUFAs, yielding 45 data points; seven investigated the impact of 3-NOP, yielding 23 data points; eight investigated the impact of essential oils on enteric methane emissions, yielding 12 data points; and three investigated the impact of monensin, yielding four data points. PUFAs significantly reduced enteric methane emissions across all metrics, although high heterogeneity remained (I² ≈ 86%–95%). 3-NOP exhibited the most substantial average reductions in enteric methane emissions;…
How strong is the evidence?
Evidence Hub reads this as a meta-analysis, done in animal, not in people. Its evidence level is 5 of 5 (Very low · case / narrative / animal / in vitro / in silico). Case reports, narrative reviews, and animal, cell or computer-model studies give the weakest evidence for human health.
Read the paper
Related studies
- Chaos and quantum thermalization
- The Dalton quantum chemistry program system
- Cord Blood Leptin and Adiponectin as Predictors of Adiposity in Children at 3 Years of Age: A Prospective Cohort Study
- Quantitative metabolomics by H-NMR and LC-MS/MS confirms altered metabolic pathways in diabetes
- Stable adiabatic quantum batteries
- A novel self-lipid antigen targets human T cells against CD1c(+) leukemias
Go deeper in Evidence Hub
Evidence Hub adds a study data sheet (design, sample size, evidence level, key numbers), an AI summary and a chat grounded in the paper's text.