Kenyan smallholder dairy farmers could reduce methane emissions and improve feed efficiency by incorporating familiar fodder shrubs into cattle diets, according to new research from the International Livestock Research Institute’s (ILRI) Mazingira Centre.
The study, published in JDS Communications, identified Calliandra calothyrsus and Leucaena leucocephala as promising additions to conventional dairy cattle feed. Laboratory experiments found that the shrubs reduced methane emissions by approximately 10–13 per cent per unit of feed, without compromising digestibility or the estimated energy supplied by the diet.
Researchers replaced about 12 per cent of a standard dairy ration, measured on a dry-matter basis, with different fodder species to evaluate their effects. Calliandra and Leucaena delivered the most promising results, suggesting that locally available plants could offer a practical approach to reducing the environmental impact of dairy production.
However, the findings remain preliminary. The experiments were conducted under laboratory conditions designed to simulate digestion, meaning further research involving live cattle is needed before recommendations can be made to farmers.
“These results are an important first step, but they now need to be validated in live animals under practical feeding conditions before recommendations can be made to farmers,” said Dr Edward H. Cabezas Garcia, who led the study.
“The goal is to identify feeding strategies that help farmers produce more milk with a smaller environmental footprint, using resources that are already available locally.”
Fodder Shrubs Offer Potential Climate Benefits
Methane is produced when microbes break down fibrous feed in a cow’s rumen, a specialised compartment of its stomach. The gas is released mainly through belching and contributes significantly to global warming. It also represents energy that could otherwise be used by the animal for production.
The research is particularly relevant to Kenya’s smallholder dairy sector, where high feed costs and seasonal shortages continue to limit productivity. During dry periods, farmers often rely on Napier grass, maize stover, crop residues and natural pastures. These feeds can limit milk production and contribute to higher methane emissions per litre of milk when diets are less efficient.
Introducing carefully managed quantities of shrub leaves could improve dietary quality, potentially helping farmers produce more milk while reducing emissions per litre. Improved feed efficiency could also reduce dependence on expensive commercial concentrates.
“Many smallholder farmers are already familiar with these shrubs because they have long been used as livestock fodder and for soil conservation,” said Dr Cabezas Garcia.
“What this research shows is that integrating them as targeted ‘methane-smart’ feeds represents an enhancement of existing systems rather than the introduction of entirely new technologies.”
Benefits Beyond Livestock Feeding
Beyond their potential role in reducing methane emissions, the shrubs offer additional agricultural benefits. They can be planted along farm boundaries, on terraces or in dedicated fodder banks, helping minimise competition with food crops.
Their ability to produce green biomass during dry periods could also provide farmers with an additional source of feed when other resources become scarce.
As legumes, both species can fix atmospheric nitrogen, contributing to soil fertility. Their leaves and prunings can also be used as mulch, while their woody stems may provide fuelwood.
These characteristics could make the shrubs valuable components of integrated farming systems that support livestock productivity, soil management and climate resilience.
Further Trials Needed Before Wider Adoption
The next phase of research will involve feeding trials with live cattle to determine whether the methane reductions observed in laboratory experiments can be replicated under practical farming conditions without compromising milk yields.
If the results are confirmed, wider adoption will depend on reliable supplies of quality seeds and seedlings, as well as practical guidance on planting, pruning and appropriate feeding rates.
The findings highlight the potential of familiar, locally grown fodder shrubs to contribute to more productive, affordable and environmentally sustainable dairy farming in Kenya. However, their effectiveness under real-world conditions must be established before farmers can be advised to adopt them specifically as a methane-reduction strategy.
