Fermentation quality of king grass (Pennisetum purpureophoides) ensiled with epiphytic lactic acid bacteria and tannin of acacia

Abstract

The aim of this study was to evaluate the fermentation quality of king grass
(Pennisetum purpureophoides) ensiled with additions of epiphytic lactic acid bacteria (LAB) prepared from fermented grass extract (FGE) or combined with tannin of acacia. Six treatments were (A) king grass without additive as a control; (B) king grass + 3% (v/w) of FGE; (C) king grass + 3% (v/w) of FGE + 10 ml of acacia extract (50 g/100 ml); (D) king grass + 3% of FGE (v/w) + 10 ml of acacia extract (50 g/75 ml); (E) king grass + 3% of FGE (v/w) + 10 ml of acacia extract (50 g/50 ml), and (F)king grass + 3% of FGE (v/w) + 10 ml of acacia extract (50 g/25 ml). About 250 g of silage materials were ensiled in 400 ml bottle silos at room temperatures (approximately 28 °C) for 30 days. Results 5 showed that the number of lactic acid bacteria in FGE was increased from 77 × 10 cfu/ml to 286 ×
5 10 cfu/ml after 2 days anaerobic incubation. Concentration of lactic acid in silages with addition of FGE or combined with tannin of acacia (B, C, D, E and F) were higher (P<0.01) than that of silage A (control). Silages with addition of FGE combined with tannin of acacia (C, D, E and F) had lower pH value than that of silages A and B. Concentrations of NH3-N was decreased with increasing concentration of tannin. Butyric acid concentration was decreased in silages of B, C, D, E and F as compared to silage A. It was concluded that addition of FGE combined with tannin prepared from acacia leaf improved fermentation quality of king grass silage.