EvaluatingCattleEmissionSamplingSchemes

This study evaluated the accuracy of daily enteric H2 and CH4 production from dairy cattle using various sampling schemes for collection of emitted gases. Gas emission data from climate respiration chambers were available from 2 experiments covering both restricted and ad libitum feeding. Generalized additive models were fitted to the data for predicting diurnal H2 and CH4 emission rates. Sampling based on 9 predetermined sampling schemes had a major impact on estimated daily H2 production, in particular with restricted feeding, whereas daily CH4 production was moderately affected by sampling scheme with restricted feeding and not with ad libitum feeding.