EVALUATION OF IN VITRO FERMETATION PATTERNS AND METHANE PRODUCTION OF MESQUITE PODS (Prosopis spp.)

Abstract

Background. Mesquite is a shrubby legume that dominates the vegetation of arid regions with multiple benefits in controlling erosive process, improving micrometeorology, and as feed source for livestock species. In addition, mesquite pods contain secondary components that could represent an option to mitigate emissions of enteric methane in ruminants. Objective. To evaluate in vitro fermentation patterns and methane production of mesquite pods (Prosopis spp.) in the arid ecoregion of the State of Hidalgo. Methodology. Mesquite pod samples were obtained from four municipalities in the arid ecoregion of the state of Hidalgo: Actopan (ACT), Tula de Allende (TUL), San Salvador (SAL) and Zimapán (ZIM). In vitro fermentation of the mesquite pods was carried out during 72 h to 39 °C in a culture medium with ruminal bacteria and mineral solutions. The fractional gas volume (Vf), cumulated gas volume (Va), maximum volume (V), gas production rate (S) and lag time (L) were calculated. The volume of methane was quantified by displacement of a NaOH 2N solution. Results. Some chemical composition characteristics of the mesquite pods were different between municipalities. V showed significant differences between localities (p≤0.05), with mesquite pods collected in SAL showing the highest values (163.2 mL g-1 MS). A municipality x time interaction was observed for Vf (p≤0.05) and differences between municipalities were observed. The values of volume partial of CH4 observed at 24 hours were different between collection sites (p≤0.05), with higher emission values observed in mesquite pods collected in SAL (16.3 mL/g MS) and ACT (17.3 mL/g MS). Conclusion. The results of the current study provide evidence of differences of in vitro fermentation patterns and methane emissions from the mesquite pods regarding to origin place. Implications. These results should be considered in the design and implementation of future nutritional and greenhouse gas mitigation strategies.