Review: Strategies for enteric methane mitigation in cattle fed tropical forages

Methane (CH4) is a greenhouse gas (GHG) produced and released by eructation to the atmosphere in large volumes by ruminants. Enteric CH4 contributes significantly to global GHG emissions arising from animal agriculture. It has been contended that tropical grasses produce higher emissions of enteric CH4 than temperate grasses, when they are fed to ruminants. A number of experiments have been performed in respiration chambers and head-boxes to assess the enteric CH4 mitigation potential of foliage and pods of tropical plants, as well as nitrates (NO3−) and vegetable oils in practical rations for cattle. On the basis of individual determinations of enteric CH4 carried out in respiration chambers, the average CH4 yield for cattle fed low-quality tropical grasses (>70% ration DM) was 17.0 g CH4/kg DM intake. Results showed that when foliage and ground pods of tropical trees and shrubs were incorporated in cattle rations, methane yield (g CH4/kg DM intake) was decreased by 10% to 25%, depending on plant species and level of intake of the ration. Incorporation of nitrates and vegetable oils in the ration decreased enteric CH4 yield by ∼6% to ∼20%, respectively. Condensed tannins, saponins and starch contained in foliages, pods and seeds of tropical trees and shrubs, as well as nitrates and vegetable oils, can be fed to cattle to mitigate enteric CH4 emissions under smallholder conditions. Strategies for enteric CH4 mitigation in cattle grazing low-quality tropical forages can effectively increase productivity while decreasing enteric CH4 emissions in absolute terms and per unit of product (e.g. meat, milk), thus reducing the contribution of ruminants to GHG emissions and therefore to climate change

A Decision Support System for smallholder campesino maize-cattle production systems of the Toluca Valley in Central Mexico. Part II—Emulating the farming system

LivestockFuturesThis paper describes the functioning and validation of the Decision Support Systems described in the first part of the paper. The DSS ran three case studies with different farm sizes that represent the range of farmers found in the Valley. The DSS results were validated against survey data for the same cases. Traditional technologies for maize and milk production were reproduced by the DSS including land use and cattle feeding systems. The generic nature of the DSS was demonstrated as well as its capacity to deal with the system's socio-economic and biological aspects. The results suggest that the DSS was successful in reproducing the functioning of the farming system's main components. More importantly it simulated the complex interactions observed between the farmers and their crops and cattle. Finally, it is acknowledged that despite the size and complexity of the DSS, it only was able to emulate the functioning of the main components of the farming system

A Decision Support System for smallholder campesino maize-cattle production systems of the Toluca Valley in Central Mexico. Part I—Integrating biological and socio-economic models into a holistic system

The objective of this work was to develop a Decision-Support System (DSS) in order to support the decision making process by campesino farmers of Central Mexico. Two biological models, one socio-economic model and a survey database form the DSS. The CERES-Maize model simulated the yield response of three local land-races of maize to different management systems. The second biological model, a cow model (dynamic hybrid model), was used to simulate alternative feeding systems. A multi-period mathematical programming model integrated the outputs of the previous models with the survey database. This model was used to find the optimal combination of resources and technologies that maximised farmers’ income. This model consists of 15,698 structural columns and 612 rows. The DSS successfully reproduced the functioning of the farming system's main components. More importantly, it simulated the complex interactions observed between the farmers and their crops and cattle, including traditional maize management practices

ESTIMACIÓN DEL CONSUMO DE PASTO ESTRELLA (Cynodon plectostachyus K. Schum.) POR VACAS LECHERAS EN PASTOREO MEDIANTE LAS TÉCNICAS DE N-ALCANOS, DIFERENCIA EN MASA FORRAJERA Y COMPORTAMIENTO AL PASTOREO

El objetivo de este trabajo fue comparar tres técnicas para estimar el consumo de materia seca (CMS) de pasto estrella por vacas lecheras en pastoreo: n alcanos, diferencia en masa forrajera y comportamiento al pastoreo. Para ello, se realizaron dos experimen tos con un diseño experimental de cuadrado latino 4 x 4 . En ambos experimentos se proporcionó 6 kg de un concentrado constituido de 8 1 % de maíz molido, 10 % de canola, 7 % de melaza y 2 % de urea más 0, 600, 900 y 1200 g de pulpa de café para cada tratamiento , respectivamente . En el experimento uno no existieron diferencias en el CMS de pasto estrella (P>0.05) entre n alcanos y diferen cia en masa forrajera con 2.9 y 3.3 kg de materia seca (MS) vaca 1 día 1 . En el segundo experimento no existieron diferencias (P>0.05) entre n alcanos y comportamiento al pastoreo en la estimación del CMS del pasto estrella con 6.7 y 6.3 kg de MS vaca 1 dí a 1 . Los n alcanos y diferencia en masa forrajera se relacionaron bien en el primer experimento (r 2 =0.80) y en el segundo experimento, los n alcanos y comportamiento al pastoreo presentaron una relación baja con un r 2 de 0.42. Se concluyó que la técnica de n alcanos , fue la más precisa para conocer el consumo de pasto estrella, de vacas en pastoreo , y que las técnicas de comportamiento al pastoreo y por diferencia en masa forrajera resultaron menos precisas . L a adición de pulpa de café entre 15 y 20% no a fect ó el consumo de pasto estrella en vacas lecheras , por lo que el empleo de este subproducto es recomendable para reducir los costos de alimentación del ganado lechero

Rendimiento total de materia seca y calidad nutritiva de hojas y tallos jóvenes de cuatro accesiones de Cratylia argentea en el trópico húmedo de Veracruz, México

Se evaluaron cuatro accesiones de la leguminosa forrajera Cratylia argentea Ciat 18516, 18666, 18668 y 18676, durante un periodo de crecimiento ininterrumpido de 12 meses, para rendimiento de forraje de hojas (HO), tallos comestibles (TC), tallos no comestibles (TN) y calidad nutritiva de HO y TC, en el estado de Veracruz, México. Los rendimientos de forraje por componente de la planta fueron similares entre accesiones: 2580±212, 33±5 y 2444±233 kg MS/ha, para HO, TC y TN, respectivamente. Las accesiones fueron similares en proteína cruda (19.10%), fibra en detergente neutro (61.10%), fibra en detergente ácido (42.20%) y lignina (14.20%). La HO presentó más proteína cruda que TC, pero fue menor con respecto a ndf, adf, y mayor en lig. Para la desaparición in situ de la MS, las accesiones difirieron en la proporción del componente altamente soluble (a) de la materia seca, pero todos tuvieron tasas de degradación fraccional (c) y materia seca lentamente degradable (b), estadísticamente similares. La producción de gas in vitro del componente hoja fue la misma para todas las accesiones. Se concluyó que, en esta evaluación, las accesiones fueron similares entre ellas

CHEMICAL COMPOSITION OF LEGUMINOUS TREE FOLIAGE AND EFFECT OF POLYETHYLENE GLYCOL ON GAS PRODUCTION AND IN VITRO DIGESTION PARAMETERS

The objective was to determine the chemical composition, digestibility and in vitro digestion parameters in ten legume tree foliage using the in vitro gas-production method with and without polyethylene glycol (PEG). The foliages with higher protein content (P<0.001) (167.1 to 180.3 g/kg DM) were A. cochliacantha, L. esculenta, E. cyclocarpum and A. farnesiana; from the total phenols (P<0.001) (365.9 to 680.6 g/kg DM) L. divaricata, H. brasiletto and C. coriaria and condensed tannins (P<0.001) (35.4 to 88.0 g/kg DM) E. cyclocarpum, A. farnesiana, P. dulce, P. acatlense and G. sepium. The in vitro dry matter digestibility was different (P<0.001) among the foliages. The in vitro gas production (IVGP), in vitro organic matter digestibility, metabolizable energy (ME), gas yield (GY24h), short chain fatty acids (SCFA) and microbial mass production (PMM), were different (P<0.0001) among the foliage as a result of the species. The use of PEG increased (P<0.0001) IVGP, ME, GY24h and SCFA in H brasiletto, C. coriaria, L. esculenta and A. cochliacantha, but affect (P<0.0001) the partition factor and the PMM. The nutritional composition and fermentation parameters in vitro between foliages differ by effect of tree and use of PEG. It is concluded that chemical composition in the foliages affect the digestibility and fermentation parameters and use of PEG increased fermentation parameters in the foliages high in secondary compounds

Enteric methane mitigation strategies for ruminant livestock systems in the Latin America and Caribbean region: a meta-analysis.

Abstract: Latin America and Caribbean (LAC) is a developing region characterized for its importance for global food security,producing 23 and 11% of the global beef and milk production, respectively. The region?s ruminant livestock sector however, is under scrutiny on environmental grounds due to its large contribution to enteric methane (CH4) emissions and influence on global climate change. Thus, the identification of effective CH4 mitigation strategies which do not compromise animal performance is urgently needed, especially in context of the Sustainable Development Goals (SDG) defined in the Paris Agreement of the United Nations. Therefore, the objectives of the current study were to: 1) collate a database of individual sheep, beef and dairy cattle records from enteric CH4 emission studies conducted in the LAC region, and 2) perform a meta-analysis to identify feasible enteric CH4 mitigation strategies, which do not compromise animal performance. After outlier?s removal, 2745 animal records (65% of the original data) from 103 studies were retained (from 2011 to 2021) in the LAC database. Potential mitigation strategies were classified into three main categories (i.e., animal breeding, dietary, and rumen manipulation) and up to three subcategories, totaling 34 evaluated strategies. A random effects model weighted by inverse variance was used (Comprehensive Meta-Analysis V3.3.070). Six strategies decreased at least one enteric CH4 metric and simultaneously increased milk yield (MY; dairy cattle) or average daily gain (ADG; beef cattle and sheep). The breed composition F1 Holstein ×Gyr decreased CH4 emission per MY (CH4IMilk) while increasing MY by 99%. Adequate strategies of grazing management under continuous and rotational stocking decreased CH4 emission per ADG (CH4IGain) by 22 and 35%, while increasing ADG by 22 and 71%, respectively. Increased dietary protein concentration, and increased concentrate level through cottonseed meal inclusion, decreased CH4IMilk and CH4IGain by 10 and 20% and increased MY and ADG by 12 and 31%, respectively. Lastly, increased feeding level decreased CH4IGain by 37%, while increasing ADG by 171%. The identified effective mitigation strategies can be adopted by livestock producers according to their specific needs and aid LAC countries in achieving SDG as defined in the Paris Agreement