Cellulose Digestibility of Fibrous Materials Treated With Trichoderma Viride Cellulase

Abstract

Cellulose digestibility of corn silage, ensiled with four percents (0, .05, .10, and .20% on a dry matter basis) of fungal cellulase, enzyme no. EC 3.2.1.4. of Trichoderma viride, was studied by the nylon bag technique with six rumen-fistulated cows. After 1 yr in the silo, cellulose content of the cellulase treated forages was lower than that of the untreated materials. Cellulase activity of the silage, at the time of feeding, as measured by “filter paper activity”, coincided closely with treatments. The pH of ensiled forage varied inversely with cellulase treatment, indicating increased fermentation of carbohydrates at higher enzyme, apparendy resulting from some breakdown of cellulose in the silo. Coefficients of cellulose digestibility for cows receiving a corn silage ration were 48 to 51% compared to only 12 to 24% for animals consuming sericea lespedeza hay.Soaking Coastal bermudagrass hay, newsprint, and Solka-floc 7 days with .72% (wt/wt) added cellulase increased cellulose digestibility when the host cows received a ration of corn silage. Mean cellulose digestion coefficients for enzyme-treated hay, newsprint, and Solka-floc were 54, 61, and 68% versus 45, 46, and 56% for controls. The enzyme treatment was ineffective in improving cellulose digestibility when the ration was Interstate sericea.In a third experiment, cellulose digestibility of bermudagrass hay, pre-soaked overnight with a 2% sodium hydroxide solution, followed by a 5-day treatment with .72% cellulase, was in the range of 59 to 61%, compared with 42% for the dry and wet controls.