Prediction of enteric methane emission from beef cattle in Southeast Asia.

Abstract

We conducted a meta-data analysis to develop prediction equations to estimate enteric methane (CH4 ) emission from beef cattle in Southeast Asia. The dataset was obtained from 25 studies, which included 332 individual observations on nutrient intakes, digestibilities, and CH4 emissions. Cattle were provided tropical forage or rice straw, with or without concentrates in individual pens equipped with indirect open-circuit head hood apparatus. The simplest and best equationto predict daily CH4 emission was CH4 (g/day)=22.71 (±1.008)×dry matter intake (DMI, kg/day)+8.91 (±10.896) [R2 =0.77; root mean square error (RMSE)=19.363g/day]. The best equationto predict CH4 energy as a proportion of gross energy intake (CH4 -E/GEI, J/100J) was obtained using DMI per body weight (DMIBW, kg/100kg), content (g/100g DM) of ether extract (EE) and crude protein (CP), and DM digestibility (DMD, g/100g); CH4 -E/GEI=-0.782 (±0.2526) DMIBW-0.436 (±0.0548) EE-0.073 (±0.0218) CP+0.049 (±0.0097) DMD+8.654 (±0.6517) (R2 =0.39; RMSE=1.3479J/100J GEI). It was indicated that CH4 emissions from beef cattle in Southeast Asia are predictable using present developed models including simple indices.