Combination effect of clove and cinnamon oil on in vitro rumen gas and methane production

Clove and cinnamon oils were used for rumen manipulation in ruminant animal production. Their major component, eugenol and cinnamadehyde were proved to optimize rumen metabolism and microbial composition. The objective of this study was to evaluate combination effect of clove and cinnamon oil on rumen gas and methane production by using an in vitro rumen fermentation system. Three ruminal cannulated cows were used as donors of ruminal fluid and were individually penned indoors. The cattle were fed daily total mix ratio (tmr – 60% concentrate 40% alfalfa hay) and had free access to water at all time. Ruminal fluid for in vitro rumen fermentation system was prepared as in vitro hohenheim gas test method. The treatments were 1) control, 2) cinnamon oil 300 ppm, 3) clove oil 300 ppm and 4) combination of clove and cinnamon oil which were assigned in order to factorial design. The results indicated that insoluble gas fraction (b; 40.8, 46.91, 40.36 and 47.46 ml respectively) and potential of extent of gas production (׀a׀ +b; 43.01, 51.03, 42.96 and 50.45 ml respectively) were significantly different (p < 0.01) between treatments. Soluble gas fraction (a) and rate of gas production (c) were not different between treatments. Clove oil, cinnamon oil and their combinations affected methane production and both essential oil decreased methane production (18.15 ml/ g dm vs 11.80 ml/ g dm and 11.55 ml/g dm, p<0.05). However there were no additive or synergistic effect when they were used together (11.80 ml/g dm vs 11.55 ml/g dm). These results explained that some essential oils were used together as blend oil may not give additional beneficial effect.