The effect of physical and biological pre-treatments of oil palm fronds on in vitro ruminal degradability

Physical pre-treatment of the oil palm frond (OPF) is known to loosen the lignocellulose while the biological pre-treatment is capable in degrading the lignin, making the substrates more accessible for rumen microbes. This study aimed at assessing the efficacy of physical, biological and combination of both pre-treatments of OPF on the in vitro ruminal degradability. Five different samples of OPF pre-treatments were used in this study; OPF was subjected to the physical pre-treatment (POPF), OPF to the biological pre-treatments using an enzyme extract of each Ganoderma lucidum (BGL) and Lentinula edodes (BLE), respectively. Another two samples were subjected to a combination of physical and biological pre-treatments of G. lucidum (CGL) and L. edodes (CLE) respectively. The control was non-treated OPF. Two fistulated Katjang goats consuming 440 g/kg OPF and 897 g/ kg commercial pellet daily on dry matter basis were used as rumen fluid donors. In vitro incubation was carried out at 39°C for 24 hours. Proportions of volatile fatty acid were measured at the end of incubation by gas chromatography. Results showed that concentrations of lignin following all pre-treatment methods were significantly lower (p