Document Type : Research Paper
Department of Animal Science, Faculty of Agriculture, Gonbad Kavous University, Gonbad, Iran
Department of Agriculture, Payame Noor University, Tehran, Iran
This experiment was conducted to study the effects of aqueous and alcoholic extracts of Camellia sinensis (L.) Kuntze leaves (green tea), Punica granatum (pomegranate-peel), and Quercus persica Jaub. & Spach (oak) at different concentrations on ruminal fermentation, dry matter and organic matter digestibility, methane production and protozoa population using gas production method. Experimental treatments were: control, 50, 100, and 200 μg/ ml aqueous and methanolic extract of Camellia sinensis, Punica granatum, and Q. persica (19 treatments in total). Cumulative gas production was recorded at 2, 4, 6, 8, 12, 24, 36, 48, 72, and 96 h after incubation. Dry matter digestibility (DMD), organic matter digestibility (OMD), metabolizable energy (ME), pH, and short-chain fatty acids (SCFA) were calculated after 24 h incubation. Gas production at different times, methane production, and protozoa population were also measured. DMD, OMD, and pH were decreased by adding extracts. Microbial mass production (MCP) and microbial mass production efficiency (EMCP) significantly increased at a low level (50 μg/ ml) and significantly decreased at high levels of extracts containing tannins (100 and 200 μg/ ml) (P< 0.01). The treatments also increased short-chain fatty acids (SCFA), reduced methane concentration, and reduced PF and protozoa populations only at the highest levels of extracts (P<0.05).