Influence Of Fibrolytic Enzymes Research Articles

Influence of fibrolytic enzymes in total mixed ration containing urea-molasses-treated sugarcane bagasse on the performance of lactating Holstein-Friesian crossbred cows.

The aim of this study was to determine the effect of different levels of fibrolytic enzyme on nutrient utilization and milk production in dairy cows. Four multiparous early-to-mid-lactation Holstein-Friesian crossbred cows were randomly allocated in a 4 × 4 Latin square design. Cows were fed a balanced total mixed ration (TMR) on a dry matter (DM) basis containing 0, 1.2, 2.4, and 3.6g/kg DM of fibrolytic enzyme in TMR, where the TMR comprises 60% concentrate supplemented with a fibrolytic enzyme at 0, 2, 4, and 6g/kg DM of concentrate, and 40% urea-molasses-treated sugarcane bagasse (UMSB) was used as a roughage source. Fibrolytic enzyme supplementation in TMR containing UMSB did not affect dry matter intake (DMI) of dairy cows (p > 0.05). There was a quadratic effect of fibrolytic enzyme levels on the digestibility of DM, organic matter (OM), neutral detergent fiber (NDF), and acid detergent fiber (ADF) (p < 0.05), and the maximal response was reached at 1.2-2.4g/kg DM of fibrolytic enzyme added in the TMR. Furthermore, 3.5% fat-corrected milk, milk fat, total volatile fatty acids, and propionic acid were greater in a cow fed with 1.2-2.4g/kg DM of fibrolytic enzyme, resulting in a lower ratio of acetic acid to propionic acid (p < 0.05). In conclusion, adding a fibrolytic enzyme in TMR containing UMSB improved nutrient utilization, rumen fermentation, and milk production of lactating dairy cows.

Influence of fibrolytic enzymes on growth performance and digestion in steers grazing stargrass and supplemented with fermented sugarcane

An experiment was conducted to evaluate the influence of exogenous fibrolytic enzymes on growth performance and digestion in steers grazing stargrass and supplemented with concentrate and sugarcane fermented. Solid state fermentation of sugar cane (SSFSC) was whole sugarcane chopped, added (dry matter basis) with urea (1.5%) and mineral premix (0.5%), and kept under shadow for 24 h. Twenty crossbreed (Brahman × Brown Swiss) steers (287±14.1 kg) grazing stargrass were individually supplemented with SSFSC (free access for 1-h period) and concentrate (1 kg/head) by 100 d. Steer were randomly assigned to concentrate with 0, 15 or 30 g fibrolytic enzyme/kg concentrate. As enzyme level increased, daily gain, intake, digestion, and improved feed conversion were linearly improved.

Influence of fibrolytic enzymes on ruminal disappearance and fermentation in steers fed diets with short and long particle length of forage

The effects of an exogenous fibrolytic enzyme mixture on in sacco ruminal disappearance and fermentation of growing (380 kg body weight) and finishing (440 kg body weight) steers fed with diets to short (10 mm) and long (50 mm) particle length (PL) were evaluated. Four Holstein steers fitted with ruminal cannulas were randomly assigned to: (1) diet with short PL forage; (2) diet with short PL forage + enzyme; (3) diet with long PL forage; (4) diet with long PL forage + enzyme.Fibrolytic enzymes did not affect dry matter intake. In growing steers, potentially disappearance fraction and total disappearance of DM, starch, NDF and ADF were increased by enzymes. In finishing steers, enzymes increased potentially disappearance fractions and total disappearance of DM, starch, NDF and ADF. In both growing and finishing steers, enzymes increased ruminal ammonia concentrations.Enzymes increased ruminal disappearance of diets for steers, but it had scarce effects on ruminal fermentation and intake.

Influence of fibrolytic enzymes on the hydrolysis and fermentation of pure cellulose and xylan by mixed ruminal microorganisms in vitro.

A series of in vitro studies was conducted to determine the effects of adding a commercial enzyme product on the hydrolysis and fermentation of cellulose, xylan, and a mixture (1:1 wt/wt) of both. The enzyme product (Liquicell 2500, Specialty Enzymes and Biochemicals, Fresno, CA) was derived from Trichoderma reesei and contained mainly xylanase and cellulase activities. Addition of enzyme (0.5, 2.55 and 5.1 microL/g of DM) in the absence of ruminal fluid increased (P < 0.001) the release of reducing sugars from xylan and the mixture after 20 h of incubation at 20 degrees C. Incubations with ruminal fluid showed that enzyme (0.5 and 2.55 microL/g of DM) increased (P < 0.05) the initial (up to 6 h) xylanase, endoglucanase, and beta-D-glucosidase activities in the liquid fraction by an average of 85%. Xylanase and endoglucanase activities in the solid fraction also were increased (P < 0.05) by enzyme addition, indicating an increase in fibrolytic activity due to ruminal microbes. Gas production over 96 h of incubation was determined using a gas pressure measurement technique. Incremental levels of enzyme increased (P < 0.05) the rate of gas production of all substrates, suggesting that fermentation of cellulose and xylan was enzyme-limited. However, adding the enzyme at levels higher than 2.55 microL/g of DM failed to further increase the rate of gas production, indicating that the maximal level of stimulation was already achieved at lower enzyme concentrations. It was concluded that enzymes enhanced the fermentation of cellulose and xylan by a combination of pre- and postincubation effects (i.e., an increase in the release of reducing sugars during the pretreatment phase and an increase in the hydrolytic activity of the liquid and solid fractions of the ruminal fluid), which was reflected in a higher rate of fermentation.