Modelling methane emissions in Mexican dairy cattle using lactation curve models

Anthropogenic methane (CH4) production is one of the most important drivers of climate change, among its main sources, dairy cattle is responsible for about 30% of all CH4 emissions in the agricultural sector. CH4 production is correlated with dry matter intake, which has been successfully modelled by lactation curve models. Directly measured CH4 production has not yet been described by these models. The objective of this study was to evaluate the following nonlinear lactation curve models: Wood, Wilmink, Ali-Shaeffer, Guo & Swalve and Pollott, to determine which model better described the CH4 production along the lactation curve in dairy cattle. CH4 measurements from 185 Holstein dairy cows, in different parities (1, 2, ≥3), were used to fit the five models. Wood’s and Guo & Swalve’s models were the only ones that fitted all individual lactations as well as the total; being Wood’s model the one that rendered the best results for modelling CH4 production along the lactation curve.