Abstract

PELAEZ-ACERO, Armando et al. Fibrolytic enzymes produced by solid-state fermentation to improve sugar cane silage. Agrociencia [online]. 2011, vol.45, n.6, pp.675-685. ISSN 2521-9766.

Grasses and forages are the principal food source for bovines in the tropic, but forage production varies in quality and quantity throughout the yeat, ditectly affecting cattle productivity. An alternative in dry seasons is the use of sugar cane (SC), howevet it has both low digestibility (20 %) and ptotein (2.5 to 4.5 %), and also a mineral imbalance. The objective of the ptesent study was to evaluate the use of whole SC in a biotechnological ptocess of solid state fetmentation (SSF) with a white tot fungus (Pleurotus sapidus). An evaluation was made of the chemical composition of the SSF on day 0 (CF-0) and 15 (CF-15) and the values of IVDMD, TP, NDF and ADF wete: 1) fot CF-0, 59.17, 2.53, 50.18 and 31.80 %; 2) fot CF-15, 65.08, 6.23, 74.24 and 60.84 %. The enzymatic activity of cellulases, xylanases and laccases was evaluated only for CF-15: 1.96, 2.08 and 5.25 IU g^-1 DM. The whole SC silage included 0, 10 and 20 % of CF-15 and changes wete evaluated in its chemical composition at 0, 8 and 16 d of silage. At 16 d the silage ptesented pH 4.2 and increase (p≤0.05) of lactic acid, acetic acid and NH₃-N; in the treatment with 20 % CF-15 thete was higher (p≤0.05) IVDMD (69.19 %) and maximum volume of in vitro gas production (207.09 mL mg^-1 DM). The analysis of the results suggests that solid ferments can be included with P. sapidus to improve the IVDMD and the fermentative vatiables of whole SC silage.

Keywords : Pleurotus sapidus; cellulases; laccases; xylanases; fiber digestibility.