EFFECT OF FIBROLYTIC ENZYMES ON CHEMICAL COMPOSITION OF MAIZE SILAGE

Abstract

This experiment was carried out to determine theeffect of enzymatic solution on bromatologic compositionand in situ degradability for neutral detergent fiber (NDF)of maize silage. The treatments were four enzymatic levels,two fermentation periods and three replications. The levelsadopted were 0, 5, 10 and 20 mg of enzyme per kg of naturalmatter (MN) of grass. Experimental silos, in triplicate, wereopened 45 and 120 days after ensiling, and DM, NDF, crudeprotein (CP), N-NH3 and pH were analyzed. In the study ofin situ degradability of DM and NDF, silage of 45 days wascollected. Nylon bag technique was used with three canulatedbovine and three incubation times (6, 24 and 96 hours). Theexperimental period was of the 36 days. The solution didn’tchange the content of DM, pH and N-NH3 values of maize silage. There was no difference on the CP amongfermentation periods of, but there was interaction betweenperiod of storage and enzymatic level. The solution increasedfinal CP of maize silage after 45 days of ensiling and thiseffect was higher to 20 mg (10.14%) compared the control(8.77%). In case of NDF, maize silage treated with 10 mglevel showed lower fiber content (47.25%) versus untreatedcontrol (49.96%), suggesting an improvement in the nutritivevalue. There was no difference among period of storageneither interaction period of storage and enzymatic level.In situ rumen degradation showed no difference among thetreatments on NDF degradation of maize silage. KEY WORDS: additives, cellulases, degradability, hemicellulases, cell wall.