Exploring tropical forage options that optimize animal production and reduce methane emissions in mixed crop–livestock systems in Ethiopia

Shimelis Gizachew Raji; Bimrew Asmare; Yohannes Ewunetu; Tesema Dangura; Marit Jørgensen; Yonas Berhanu

doi:10.1071/CP25085

RESEARCH ARTICLE (Open Access)

Exploring tropical forage options that optimize animal production and reduce methane emissions in mixed crop–livestock systems in Ethiopia

Shimelis Gizachew Raji ^A , Bimrew Asmare ^B , Yohannes Ewunetu ^B , Tesema Dangura ^C , Marit Jørgensen ^D and Yonas Berhanu

^C ^*

+ Author Affiliations

- Author Affiliations

^A School of Plant and Horticultural Sciences, Hawassa University, Hawassa, Ethiopia.

^B Department of Animal Sciences, Bahir Dar University, Bahir Dar, Ethiopia.

^C School of Animal and Range Sciences, Hawassa University, Hawassa, Ethiopia.

^D Department of Grassland and Livestock, Norwegian Institute of Bioeconomy Research (NIBIO), Ås, Norway.

^* Correspondence to: yonasb@hu.edu.et

Handling Editor: Christian Huyghe

Crop & Pasture Science 76, CP25085 https://doi.org/10.1071/CP25085

Submitted: 9 April 2025 Accepted: 27 July 2025 Published: 27 August 2025

© 2025 The Author(s) (or their employer(s)). Published by CSIRO Publishing. This is an open access article distributed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License (CC BY-NC-ND)

Abstract

Context

Tropical forages can improve livestock productivity while reducing methane emissions in smallholder crop–livestock systems.

Aims

This study evaluated forage mass, forage quality, methane mitigation potential of 12 tropical species at two contrasting sites in the Ethiopian highlands: Hawassa in the south and Bahir Dar in the north.

Methods

Field experiments were conducted from 2021 to 2023, with two to four cuts per year by using a randomized complete block design. Plant samples were also evaluated for chemical composition and in vitro methane production.

Key results

Results showed significant site-specific variations, with desho grass (Pennisetum pedicellatum) demonstrating consistently high forage mass production (27.3 Mg ha⁻¹ at Hawassa; 17.58 Mg ha⁻¹ at Bahir Dar) across these environments. Legumes, particularly sunnhemp (Crotalaria juncea L.) and lablab (Lablab purpureus L.), exhibited the highest crude protein yield (590–1300 kg ha⁻¹ year⁻¹) but lower forage production, highlighting their role as supplemental feed sources. Methane mitigation potential also exhibited variations, with lablab, Mombasa (Megathyrsus maximus) and desho producing the lowest emissions (<16%), whereas high-emission species such as Greenleaf desmodium (Desmodium intortum) (>27%) warrant further evaluation.

Conclusions

The study identified desho and Mombasa as promising options for site-specific forage development because of their dual benefits of productivity and in vitro methane mitigation. Legumes such as sunnhemp and lablab are recommended as high-quality supplements to existing feeding strategies.

Implications

These findings have provided actionable insights for extension officers, policy makers and researchers seeking to balance livestock productivity with environmental sustainability in Ethiopian highlands. Future research should focus on validating methane mitigation potential under in vivo conditions and addressing challenges in legume establishment.

Keywords: Ethiopian highlands, forage mass, forage quality, grasses, legume establishment, legumes, methane mitigation, protein yield.

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