TY - SER AU - Sallam,Sobhy M. TI - Effect of different levels of citrus essential oil and its active component on rumen microbial fermentation and methane emission in vitro KW - Citrus oils KW - Analysis KW - Limonene KW - Protozoa KW - Evolution KW - Methane KW - Combustion KW - Metabolism KW - Gas production KW - Essences and essential oils KW - Microbiology KW - Physiological effect KW - Methane industry KW - Egypt KW - Rumen Microbiology KW - Rumen fermentation N1 - Includes references N2 - The fermentation characteristics of adding different levels (0, 25, 50 and 75 µ1/75ml buffered rumen fluid) of citrus essential oil or its bioactive component (limonene, 0, 30, 45 and 60 jllJ75mJ buffered rumen fluid) to a basal substrate (50% roughage: 500-10 concentrates) were evaluated in vitro by semi automatic gas production (GP) technique. The investigated essential oil was Citrus reticulata (CR25, CR50, CR7S), and Limonene (L30, L45, L60). The analyses of the citrus essential oils by GC/MS showed that the main components were dl-Limonene (83.9%) and ¥- Terpinene (JO.7.5%).There were significant differences (P < 0.05) in cumulative OP after subtracting the blank gas volume for different levels of citrus essential oil or limonene. All levels of citrus essential oil and limonene significantly (P