Greenhouse Gas (GHG) Emission Estimation for Cattle: Assessing the Potential Role of Real-Time Feed Intake Monitoring

Abstract

This study investigated the impact of feeding systems on the determination of enteric methane (CH4) emissions factor in cattle. Real-time feed intake data, a crucial CH4 conversion rate (Ym value) parameter, were obtained using a roughage intake control (RIC) unit within a smart farm system. Greenhouse gas (GHG) emissions, including CH4 and carbon dioxide (CO2), from Holstein steers were monitored using a GreenFeed (GF) 344 unit. The results revealed satisfactory body weight (383 ± 57.19 kg) and daily weight gain (2.00 ± 0.83 kg), which are crucial factors. CO2 production exhibited positive correlations with the initial body weight (r = 0.72, p = 0.027), feed intake (r = 0.71, p = 0.029), and feed conversion ratio (r = 0.69, p = 0.036). Five different emission factors (EFs), EFA (New Equation 10.21A) and Equation 10.21 (EFB, EFC, EFD, and EFE), were used for GHG calculations following the Intergovernmental Panel on Climate Change (IPCC) Tier 2 approach. The estimated CH4 EFs using these equations were 69.91, 69.91, 91.79, 67.26, and 42.60 kg CH4/head/year. These findings highlight the potential for further exploration and adoption of smart farming technology, which has the potential to enhance prediction accuracy and reduce the uncertainty in Ym values tailored to specific countries or regions.