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\hypersetup{pdftitle={Effects of Yucca Schidigera Extract on Ruminal Fermentation and Methane Emission in Vitro},pdfauthor={Hongrong Wang, Guoxiang Li},pdfsubject={Tropentag 2016: Abstract},pdfkeywords={Methane emission, Protozoa biomass, Ruminal fermentation, yucca schidigera extract},pdfpagemode=None,colorlinks=true}
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\parbox[b]{13.4cm}{\centering \large{\textbf{Tropentag, September 18-21, 2016, Vienna, Austria}}\\[1ex] \Large{``Solidarity in a competing world ---\\fair use of resources''\\[2ex]}}
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\Large{\textbf{Effects of Yucca Schidigera Extract on Ruminal Fermentation and Methane Emission in Vitro\footnote{\textbf{Contact Address:} Hongrong Wang, Yangzhou University, College of Animal Science and Technology, No.48 Wenhui Estern Road, 225009~Yangzhou, China, \mbox{e-mail}: \email{hrwang@yzu.edu.cn}}\\[0.8ex]}}
\normalsize{\textsc{Hongrong Wang$^{1}$, Guoxiang Li$^{2}$}}
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\begin{itemize*}
\item[]{\small{\textit{$^{1}$Yangzhou University, College of Animal Science and Technology, China}}}
\item[]{\small{\textit{$^{2}$Yangzhou University, College of Animal Science and Technology, }}}
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\index[author]{Wang, Hongrong}
\index[author]{Li, Guoxiang}
\begin{center}
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\textbf{Abstract}
\begin{abstract}
\normalsize{
Generation of methane from ruminants, represents 2---\mbox{12\,\%} of gross energy intake and contributes approximately \mbox{16\,\%} of global methane emissions. In addition, production from ruminants contributes to total global methane production, which is an important contributor to global warming methane production by ruminants. Therefore, extensive research interests have been focused on methods of reducing methane production in the rumen. In this paper, \textit{in~vitro} experiments were conducted to determine the effects of different additional doses of yucca schidigera extract (YSE) on ruminal fermentation and methane production, by 3 goats fitted with rumen cannula. The mixture of rice straw, corn and soybean meal were used as substrate for \textit{in~vitro} fermentation, and the YSE was set as 0, 2, 4, 6, 8 mg per 1 g substrate respectively. The experimental results were described as follow: except the group containing \unitfrac[8]{mg}{g} YSE, the pH value increased with YSE increasing ($p < 0.05$), and higher in the group containing 6 mg YSE. Quite the reverse, except the highest dose of \unitfrac[8]{mg}{g} YSE, NH$_{3}^{}$-N concentration, CH$_{4}^{}$ production, accumulated gas production, and protozoa density tended to decrease in general, according with the increase of YSE level. The concentration of acetate, propionate, butyrate and total VFA was also suppressed by YSE. Further observed that, the ratios of acetate: propionate (A: P) varied with treatments, and lowest in the group containing \unitfrac[6]{mg}{g} YSE ($p < 0.05$). These results suggest that, as a rumen manipulating agent, YSE could be useful in limiting methane production, and stabilising ruminal fermentation environment. Based on this work, \unitfrac[6]{mg}{g} in substrate was appropriate dose for rumen fermentation. }

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\noindent \textbf{Keywords:} Methane emission, Protozoa biomass, Ruminal fermentation, yucca schidigera extract
\index[key]{Methane emission}
\index[key]{Protozoa biomass}
\index[key]{Ruminal fermentation}
\index[key]{Yucca schidigera extract}
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