In vitro gas production parameters of <i>Ficus vogelli</i> diets in the dry and wet seasons of Nigeria

Abstract

The nutritive value of Ficus vogelli (FV) in mixtures with Panicum maximum (PM) at four different treatment levels were assessed through the determination of the proximate composition and in vitro fermentation of diets in two seasons (dry and wet). Nutrient composition and qualitative analysis of secondary metabolites (saponin and tannins) of FV were determined. In vitro gas production (IVGP, ml/200 mg DM), Organic matter digestibility (OMD %), Metabolizable energy (ME, MJkg-1 DM), Short chain fatty acids (SCFA, ml), and Methane production (ml/200 mg DM) were also estimated. Crude Protein (CP), Crude Fibre (CF), Ether Extract (EE), Ash, and Neutral Detergent Fibre (NDF) for FV in the dry and wet seasons were: 16.66 and 12.11, 30.25 and 35.00, 18.90 and 20.50, 11.00 and 12.95, 74.50 and 63.50 g/100g DM respectively. FV contained saponin and tannins in both dry and wet seasons. ME, OMD and SCFA for diets of FV were not significantly (P>0.05) affected by levels of inclusion of Ficus in the wet season. However, in the dry season, OMD (69.83) was highest (P<0.05) in the (T2) FV diet. Gas production characteristics for FV diets were similar among treatments in the wet season. Soluble fraction (a) ranged from 1.33(T4) to 3.33 (T2) in the wet season and from 4.50 (T4) to 5.33 (T3) in the dry season. Potential gas production (b) and the potentially degradable fraction (a+b) of the sole PM diet (T1) was significantly (P<0.05) higher than the sole FV diet (T4) in the dry season. Rate of gas production (c) was similar among treatments in both seasons. Methane (ml/200mg DM) production for FV diets ranged from 21.33 – 32.00 (dry season) and 7.67 - 12.00 (wet season), the highest being (T2) in both seasons and least from T4 in DS and T1 in WS. Results showed that FV has potentials as dry season forage supplements for ruminants.

Key words: Ficus vogelli, Panicum maximum, dry season, in vitro gas production.