In vitro evaluation of Napier grass-oil palm frond combination as ruminant feed

The effects of different combinations of Napier grass (Pennisetum purpureum) and oil palm (Elaeis guineensis Jacq) fronds on ruminal fermentation patterns in vitro in goats were investigated. Rumen liquor from three 2-year-old Kacang-crossbred goats was mixed with buffer and substrates. Four dietary treatments were compared namely 100% concentrates (CON), 50% OPF with 50% concentrates (OPF 50), 50% Napier grass with 50% concentrates (NP 50), and 25% Napier grass, 25% OPF and 50% concentrates (NP-OPF)). Incubation of the mixture was carried out at 39°C for 24 h. Total gas production (GP) was recorded after 2, 4, 6, 8, 10, 12 and 24 h of incubation. Rumen fluid pH, methane gas, total volatile fatty acids and in vitro dry matter digestibility (IVDMD) were determined at the end of incubation. Long chain fatty acid (LCFA) profiles were obtained in separate runs to determine the apparent biohydrogenation (BH) of linoleic (C18:2n-6) and α-linolenic acids (C18:3n-3). Cumulative gas production was significantly higher for the CON group (P<0.05) but not significantly different in the other groups. The NP 50 diet produced significantly higher methane (P