17 H. Jahani-Azizabadi2 Z. Durmic J. Vadhanabhuti P. E Vercoe Journal of Animal and Plant Sciences JAPS 20192019/02/01 29 1 8-15 1018-7081 N/A <p>The aim of the present study was to investigate the dose-response effect of selected Australian EOs on in vitro rumen<br>fermentation characteristics in order to find a combination of EO and dose that may be effective against methane and<br>ammonia-N, while maintaining rumen fermentation. Selected EO treatments significantly (P&lt;0.05) reduced methane<br>(between 25% and 97% reduction) and ammonia-N (between 19% to 70% reduction) concentrations when compared to<br>control, and change occurred in a dose-dependent manner. However, other fermentation parameters were also reduced in<br>all of these, but in Santalum spicatum EO treatment the effect on methane (50% reduction) and ammonia-N (59%reduction) were greater than the effect on overall fermentation (i.e. VFA reduced only up to 20%). Results of the present<br>study demonstrated that at doses tested, it was not possible to dissociate the effects of EOs on in vitro fermentation,<br>except in S. spicatum EO, where selected doses may reduce methane and ammonia N with less negative effect on overall<br>fermentation by rumen microbes.</p> essential oils, methane, ammonia-N, rumen fermentation, in vitro. Pakistan Agricultural Scientists Forum https://thejaps.org.pk/AbstractView.aspx?mid=AS-17-0118