PSIII-1 Impact of low Levels of Tannin Supplementation on Enteric Methane Emissions and Performance in Organic Dairy Heifers

Abstract Condensed tannins are theorized to reduce enteric methane emissions by enhancing protein efficiency and decreasing ruminal fiber fermentation in ruminant animals. The objective of this study was assess the viability supplemented condensed fed at increasing levels: 0% (CON), 0.075% (LOW), 0.15% (MED), 0.30% (HIG) dry matter intake (DMI). acclimation utilized 24 organic Holstein heifers, one GreenFeed emission measurement system, two SmartFeed Pro systems (C-Lock Inc., Rapid City, SD), individual animal feeding stanchions. Twenty heifers (BW = 218.75 ± 16.78 kg) were selected based on stratified into treatment groups initial body weight status. A 7-d covariate gas analysis performed prior account for differences. Daily, offered 1 kg starter calf feed tannin stanchions 45-d a basal TMR diet through systems. Statistical conducted R with fixed effect pre-trial rate as covariate. Daily production ranged from 141 152 g (CH4)/day between treatments. No significant difference observed treatments daily (P=0.53), yield (g CH4/ DMI; P=0.82), or intensity CH4/kg gain; P=0.62). Similarly, not DMI (P=0.95), average gain (ADG) (P=0.50), (P=0.36). However, ADG continued increase throughout study, suggesting that supplemental did negatively impact performance. results would indicate low levels supplementation alter CH4 heifers.