Prediction of enteric methane production from dairy cows

The main objective of this study was to elucidate the potential for prediction of enteric methane (CH4) emissions from dairy cows by using predicted rumen plus hindgut digested (fermented nutrients) and total tract digested nutrients (by using NorFor) as input variables. Twenty-one experiments (78 dietary treatments) were collected. The data-set was used to develop prediction models and to test their and extant models ability to predict enteric CH4 emissions. Models were compared based on mean squared prediction error and concordance correlation coefficient (CCC) analysis. Fermented nutrients did not predict enteric CH4 emissions adequately (CCC < 0.420). Including total digested (td) nutrients in the model [CH4 (MJ/d) = -2.13 + 1.64 tdOM (kg/d) -9.74 tdFat (kg/d) + 1.64 tdNDF (kg/d)] predicted enteric CH4 emissions more precisely (CCC = 0.733), and showed an improvement in the prediction of enteric CH4 emissions over the extant models tested.