Effect of Some Plant Essential Oils on In vitro Ruminal Methane Production and on Fermentation Characteristics of a Mid-forage Diet

The objective of the present study was to investigate the effect of different doses of some ۷ natural semi-arid medicinal plants’ essential oils on in vitro ruminal digestion and fermentation patterns of a mid-forage (alfalfa hay: concentrates, ۱:۱) diet. Treatments consisted of either basal diet alone (control) or added with ۳۵, ۷۰, ۱۴۰ or ۲۸۰ µl L-۱ of coriander, oregano, caraway, cumin, cinnamon, pistachio hull and thyme essential oils, incubated for ۲۴ hours at ۳۸.۷ºC. The essential oils of cinnamon and pistachio applied as ۲۸۰ µl L-۱ and thyme applied at ۱۴۰ and ۲۸۰ µl L-۱ caused a decrease in DM disappearance as compared with control. Thyme and pistachio essential oils (used at ۲۸۰ µl L-۱) resulted in a decrease of NDF disappearance, while caraway (۷۰ µl L-۱) and cumin (۱۴۰ µl L-۱) resulted in an increase in it (۱۴.۸% and +۱۸.۲%, respectively). Relative to control, the essential oils applied, did not significantly affect the medium N-NH۳ concentration (except thyme at ۱۴۰ and ۲۸۰ µl L-۱), pH (except thyme and cumin essential oils, ۶.۴۱ and ۶.۲۲ vs. ۶.۳, respectively), gas produced (except thyme at ۲۸۰ µl L-۱) and Feed Fermentation Efficiency (FFE). Relative to control, addition of all the essential oils resulted in a decrease of CP disappearance and CH۴ (except for cumin) production as Mm-۱ incubated. Findings revealed that these essential oils may allow manipulation of rumen microbial fermentation.

کلیدواژه ها:

Essential oil ، In vitro ، Methane ، Rumen