An opportunity to reduce emissions by improving livestock feeding is investigated in Nicaragua
Livestock is frequently associated with negative environmental impacts such as deforestation for cattle grazing, soil degradation, loss of biodiversity, and greenhouse gas (GHG) emissions released into the atmosphere such as nitrous oxide (N2O), carbon dioxide (CO2), and methane (CH4), which result in rising global temperatures and melting of glaciers, water scarcity, and extinction of up to 30% of animal species, among other effects.
Methane is especially particular, since it is a greenhouse gas 23 times more polluting than CO2, and the largest source of methane emissions does not come from soil or crops (e.g, rice) but from the digestive process of livestock, known as enteric fermentation.
What is enteric fermentation?
The microbial flora in one of a cow’s four stomachs digests the carbohydrates present in the plants (fodder) ingested by the animal to obtain energy. A residue of this process is methane, and the quantity of this GHG emitted from this process is directly related to the quality of the fodder that cows eat. That is, the lower the amount of protein and the higher the structural carbohydrates of the forage consumed by a cow, the greater the amount of methane that will be emitted as a residual effect.
This usually happens with animals that graze in paddocks with aged forages, which are difficult to digest for the animal. Furthermore, a high fiber content affects the potential consumption of forage by the animal, by increasing its retention time in the rumen, thus decreasing the voluntary consumption of food, which becomes a limiting factor to meat and milk production.
In Nicaragua, cattle ranching is an important part of the economy, as well as the main component of livelihoods in municipalities such as Camoapa (Boaco) and Matiguás (Matagalpa), where 78% of farming families derive their livelihoods from it. Both zones are located in the Central Region of Nicaragua, and their predominant livestock production system is dual purpose (meat and milk). However, these systems have deficiencies in livestock feeding, due to the low availability of forage during the dry season of the year and the degradation of grazing areas due to inadequate management. As mentioned above, poor livestock nutrition indirectly increases the environmental footprint of livestock in those territories.
After the signing of the Paris Agreement, the Nicaraguan Government committed to seeking and implementing strategies to reduce GHG emissions. By improving livestock feeding and livestock productivity, this becomes a triple-win scenario for the country, their farmers, and environment.
During 2017, a group of researchers from the International Center for Tropical Agriculture (CIAT), seeking to contribute to countries’ commitments to reducing emissions without compromising productivity, evaluated GHG production of typical legumes (trees, perennial herbs, and shrubs) and grasses used as cattle feed in the two Nicaraguan municipalities. To this end, in vitro procedures were carried out in the laboratories of CIAT’s headquarters with forage grasses collected in these two places.
The samples included the grasses Brachiaria brizantha cv. Marandu, Brachiaria hybrid cv. Mulato II, and the legume Cratylia argentea. The results showed that the legume evaluated provided high protein content (22.6%) and low fiber content (57%, compared to 70% observed in grasses).
These parameters positively affect animal productivity by producing more milk or gaining more weight in less time and by releasing less methane into the atmosphere. This was corroborated by measuring the gas production, which was 1.35 times higher in the Brachiaria grasses than in C. argentea (see graph below).
The results of this work raise the real possibility of reducing methane emissions from the agricultural sector in Nicaragua and contributing to reducing global temperature caused by GHG emissions, by improving cattle feed. In addition, it is a climate-smart practice, which improves the productivity of the livestock sector, while contributing to climate change mitigation and adaptation. The joint work of CIAT and partners in Nicaragua will help boost the research on and, most importantly, the adoption of these measures in the field to increase livestock productivity and reduce GHG emissions.
This study was carried out within the framework of the CGIAR Research Program (CRP for its acronym in English) Livestock, and its thematic axis ‘Livestock and environment’. Similar studies are conducted in Colombia and Costa Rica under the LivestockPlus Project, supported by the CGIAR Research Program on Climate Change, Agriculture and Food Security (CCAFS). Authors of the blog: Isabel Molina, Johanna Mazabel, Stiven Quintero, Martin Mena and Jacobo Arango, from the CIAT Tropical Forages Program.
This study was carried out within the framework of the CGIAR Research Program (CRP) Livestock, in the Livestock and environment flagship. Similar studies are conducted in Colombia and Costa Rica under the LivestockPlus Project, supported by the CGIAR Research Program on Climate Change, Agriculture and Food Security (CCAFS). Authors of the blog: Isabel Molina, Johanna Mazabel, Stiven Quintero, Martin Mena and Jacobo Arango, from the CIAT Tropical Forages Program.
 IPCC (Intergovernmental Panel on Climate Change). 2007. Climate Change 2007: Synthesis Report. (C. W. Team, R. K. Pachauri, & A. Reisinger, Edits.) Retrieved on 22 December 2017, from www.ipcc.ch/publications_and_data/publications_ipcc_fourth_assessm
 CENAGRO. 2013. Base de Datos. IV CENAGRO 2011. Instituto Nacional de Información de Desarrollo INIDE. Managua, Nicaragua.