Sustainability & efficiency

From Productivity to Climate Action: Harnessing Community-Based Breeding to Lower Methane Emissions in Ethiopian Smallholder Sheep Systems

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Abstract

The global focus on ways of mitigating methane (CH₄) emissions from livestock has intensified as climate change has become a global challenge threatening agricultural food systems and the livelihoods of smallholder farmers in particular. Although Africa contributes approximately 8% of global methane emissions, efforts to translate mitigation and adaptation strategies into national policies and on-farm actions remain limited. Community-Based Breeding Programs (CBBPs), which have demonstrated strong potential to improve productivity and income among smallholder farmers, may also serve as an entry point for integrating low-emitting animals into genetic improvement schemes. This study aimed at evaluating the impact of a decade of selection for productivity within CBBPs on methane emissions in Bonga sheep. A total of 400 sheep of various ages and physiological categories were selected for the study in the Bonga region, Ethiopia, including CBBP animals that have been selectively bred for body weight and litter size and non-CBBP animals representing unselected, traditionally managed animals in village flocks. Methane concentration was recorded using a Laser Methane Detector (LMD) positioned one meter from the animal for 30 minutes daily during three consecutive days. Raw data were cleaned and processed to derive multiple CH₄ phenotypes, including the overall mean (muGlob), sum of peaks (SoP), and area under the curve (AUC). Results revealed a significant reduction in methane emissions among CBBP animals compared to non-selected flocks. After accounting for fixed effects such as physiological category, feeding time, day of measurement, diurnal period, sex, and year, CBBP animals emitted on average 4.35% less methane for muGlob, 4.20% less for AUC, and 14.27% less for SoP (P = 0.017, P = 0.135, and P = 0.007, respectively). This indicates that selection for productivity has indirectly contributed to reduced methane output. Heritability estimates (h²) based on pedigree data ranged from 0.08 for AUC to 0.22 for muGlob and 0.13 for SoP, suggesting low to moderate additive genetic effects. Corresponding repeatability estimates (r) were 0.099 for AUC, 0.126 for SoP, and 0.802 for muGlob, indicating variable consistency across repeated measurements. These results indicate that LMD-based methane phenotypes are heritable and repeatable and could therefore be considered for selection toward lower CH₄ emission. Furthermore, we anticipate that increasing sample size, incorporating genomic relatedness, and accounting for additional variation factors such as feeding time, time of measurement during the day, and animal age will improve the precision of genetic parameter estimates for methane phenotypes. Simulating expected genetic progress under breeding objectives that jointly consider productivity and methane emission would further support the design of climate-smart breeding strategies.

Keywords: 2026

How to Cite:

Getachew, T., Haile, A., Rekik, E., Rischkowsky, B., Sölkner, J., Solomon, D. & Wurzinger, M., (2026) “From Productivity to Climate Action: Harnessing Community-Based Breeding to Lower Methane Emissions in Ethiopian Smallholder Sheep Systems”, World Congress on Genetics Applied to Livestock Production Digital Archive 2026(1): 2283092. doi: https://doi.org/10.31274/wcgalp.23480

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