This paper reviewed uncertainties and discrepancies in CH4 inventories as related to livestock emissions, enteric CH4 measurement methods, and DMI and CH4 prediction models. Enteric CH4 prediction models were based on various animal or feed characteristic inputs but were dominated by DMI in one form or another. As a result, accurate prediction of DMI is essential for accurate prediction of livestock CH4 emissions. Analysis of a large data set of individual dairy cattle data showed that simplified enteric CH4 prediction models based on DMI alone or DMI and limited feed- or animal-related inputs can predict average CH4 emission with a similar accuracy to more complex empirical models. These simplified models can be reliably used for emission inventory purposes.
Hristov A, Kebreab E, Niu M, Oh J, Bannnk A, Bayat A, Boland T, Brito A, Casper D, Crompton L, Dijkstra J, Eugène M, Garnsworthy P, Haque N, Hellwing A, Huhtanen P, Kreuzer M, Kuhla B, Lund P, Madsen J, Martin C, Moate P, Muetzel S, Muñoz C, Peiren N, Powell J, Reynolds C, Schwarm A, Shingfield K, Storlein T, Weisbjerg M, Yáñez-Ruiz D, Yu Z
Journal of dairy sciences