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The inclusion of Tithonia diversifolia in pasture-based diets is a promising alternative to increase bovine productivity, due to its chemical composition and wide adaptation, but there are few in vivo studies to determine its effect on methane yield and animal production in grazing systems. The objective of this study was to determine the effects of the T. diversifolia inclusion in a basal diet of Brachiaria humidicola on methane (CH4) emissions by enteric fermentation, and on milk yield and quality in dual-purpose cows. The polytunnel technique was used for the determination of methane yield and two diets were evaluated (Diet 1: Brachiaria humidicola 100%; Diet 2: T. diversifolia 15% + B. humidicola 85% dry matter basis) in the moderate rainy and rainy seasons using a cross-over experimental design; milk production was measured by daily milk weighing, and milk quality was determined using a LACTOSCAN analyzer. The inclusion of T. diversifolia did not increase the dry matter intake (P = 0.369), but increased the intake of crude protein and minerals, and reduced fiber intake, resulting in the increased yield of milk and its components in the moderate rainy season (P = 0.012). The inclusion of T. diversifolia reduced the absolute CH4 emissions (P = 0.016), Ym and emission intensity (per unit of fat, protein and kilogram fat and protein corrected milk yields) both in the moderate rainy and rainy seasons (P

Tithonia diversifolia is a shrub with excellent forage characteristics that has shown a wide genetic and phenotypic diversity. The objective of this study was to determine the biomass production and nutritional quality of seven genotypes of T. diversifolia with outstanding characteristics for ruminant nutrition, to analyze the Genotype x Environment (GxE) interaction of biomass production and to compare the performance of these genotypes with grasses offered normally in tropical conditions. For the GxE interaction the AMMI and SREG models were used, and evaluations were made in three environments. In the GxE analysis, the interaction was significant and effects of the environment on biomass productivity were observed with differences between genotypes (p

Tithonia diversifolia (Mexican sunflower) is a shrub used for animal feed that has outstanding agronomic and chemical characteristics. Its potential to modify the dynamics of fermentation and improve the supply of nutrients to ruminants has received considerable attention. This study was designed to determine the effect of different genotypes of T. diversifolia on ruminal fermentation and degradation of dry matter (DM), concentration of volatile fatty acids, and production of methane (CH4) when mixed with a low-quality tropical grass, Urochloa brizantha (palisade grass). In a randomised complete block design, mixtures of seven genotypes of T. diversifolia with U. brizantha cv. Marandú were evaluated by using the in vitro gas production technique. The effect of fertilisation was also evaluated for each genotype. Inclusion of T. diversifolia significantly (P < 0.05) increased the supply of nutrients and modified fermentation parameters. DM degradation of biomass after 72 h was greater in the presence of T. diversifolia than for feeds based only on U. brizantha (68.0% vs 63.4%; P < 0.01). CH4 production was lower (P < 0.05) during fermentation with some T. diversifolia genotypes (25.3 vs 27.7 mg CH4 g–1 incubated DM), and the acetic:propionic acid ratio was also lower. Fertilisation of T. diversifolia genotypes increased DM degradation, increased the content of certain nutrients (e.g. crude protein) and modified CH4 production. Therefore, inclusion of T. diversifolia in mixtures based on low-quality tropical grasses such as U. brizantha increases the supply of nutrients (crude protein, minerals, energy) and can modify the products of enteric fermentation, with some genotypes decreasing enteric CH4 emissions.

The inclusion of

Plenary paper presented at the International Leucaena Conference, 1‒3 November 2018, Brisbane, Queensland, Australia.Leucaena leucocephala has played a key role in the development of sustainable cattle ranching in Latin America. This species is the backbone of the so-called Intensive Silvopastoral Systems (ISPS) that combine high-density cultivation of leucaena as fodder shrubs (4,000–40,000 plants/ha) with grasses and trees. The layers of vegetation added by shrubs and trees increase the system’s capacity for transforming solar energy into biomass and enhance habitat complexity. Although part of the biomass is transformed into livestock products, a significant amount is deposited as litter on the soil and, along with the nitrogen fixed by leucaena and other trees, has positive effects on soil properties and grass production. The increased complexity of the system has measurable effects on biodiversity. ISPS with leucaena support more species of birds, ants, dung beetles and woody plants than conventional pasture monocultures, contribute to landscape-scale connectivity and provide environmental services. They also enhance animal welfare through reduced heat stress and improved availability and quality of fodder resources. ISPS contribute to climate change mitigation by improving above- and below-ground carbon sequestration and by cutting down greenhouse gas emissions per units of dry matter consumed and cattle product. Although these systems have been successfully implemented in Colombia, Mexico and other countries, their adoption is still limited in relation to the area suitable for their introduction.

The production of beef and milk has a significant impact on climate change, as these activities are responsible for a large proportion of the greenhouse gases emitted in agriculture. We used the static closed chamber technique to measure the rate of CH4-C, N2O-N and CO2-C emissions from pastures (102 days) and bovine excretions (27 days) in an intensive pasture monoculture (PM) and an intensive silvopastoral system (ISS) in the Cauca Valley of Colombia. Mean soil CO2-C (mg m2 h−1), CH4-C and N2O-N emissions (μg m−2 h−1) were 236.7 versus 113.4; 46.7 versus 1.01 and 344.7 versus 40.1 for the PM and ISS, respectively. The accumulated flows for PM and ISS during the evaluation period were 751.6 and 424.3; 4.39 and − 0.41; and 12.75 and 1.55 (kg ha−1) for CO2-C, CH4-C and N2O-N, respectively. Regarding manure, the PM had lower CO2-C and CH4-C emissions (498.6 vs. 981.2 mg m−2 h−1, and 1.9 vs. 4.7 μg m2 h−1; p > 0.05), and higher N2O-N emissions (2967.3 vs. 1179.8 μg m−2 h−1; p = 0.02) than the ISS, respectively. For the urine patches, the ISS emitted only 47.9, 2.2 and 11.6% of the CO2-C, CH4-C and N2O-N emissions observed in the PM, respectively. Moreover, comparing both systems with a forest, CH4-C and N2O-N emissions from the ISS were not different (p > 0.05), but the PM presented higher emissions for the three gases (p

Intensive Silvopastoral Systems (ISPS) are agroforestry arrangements that combine high-density cultivation of fodder shrubs (4000–40,000 plants ha−1) with improved tropical grasses, and trees or palms at densities of 100–600 individuals ha−1. The ISPS were initially developed in Colombia and have expanded to Mexico and Brazil, among other countries. The main fodder shrubs currently used are Leucaena leucocephala and Tithonia diversifolia due to their fast growth, tolerance to heavy grazing by cattle, and reduction in the emissions of greenhouse gases. Among their advantages, ISPS produce more edible dry matter and nutrients per hectare; increase milk or meat production while reducing the need of chemical fertilizers and concentrate feeds, thus improving farm profitability; increase carbon sequestration and reduce methane emissions from enteric fermentation; and improve animal welfare and biodiversity. The present chapter is a review of recent experiences and research findings in ISPS in Latin America and their effect on production efficiency, greenhouse gas emissions, and economic performance. It also reviews the need of public policy and research to improve access to capital, incentives, and extension services in cattle ranching areas to promote ISPS. ISPS are an important tool in supplying beef and dairy products for local and global markets, while also providing environmental services and increasing resilience to climate change.