Authors : J.E. Guerra Liera , E. Ibarra Lopez , L.E. Soto Angulo , J.J.R. Hernandez Moreno , J.L. Corrales Aguirre , J. Rodriguez Garcia , L.A. Lopez Juarez and A. Cordova-Izquierdo
Abstract: Animal production is improved by the use of exogenous enzymes during feeding that modify solubility and digestibility of fiber, which favors a greater ruminal microorganisms activity, this improves profitability of ruminant diets based on grain and forages. There are evidences of the use of these enzymes on diets with a 78% of concentrate, where there was an increase of 25% of NDF ruminal digestion, better than 18% when using 25% of forage. In this research a xilanase enzyme was evaluated Fibrozyme (Alltech, Inc.) which is composed of fermentation extracts of Aspergillus niger and Trichoderma longibrachatium, in four treatments: T1 = only alfalfa or control (1), T2 = alfalfa plus Fibrozyme (1), T3 = alfalfa plus Fibrozyme (2) and T4 = 40% concentrate plus 60% of alfalfa without Fibrozyme (2), the first two with a basal diet 1 = 100% alfalfa and the last two with 2 = 40% alfalfa plus 60% concentrate for 10 days. The enzyme was given at a dose of 14 g d-1, 7 g at 0800 and 7 g at 2000. Two male animals � Holstein-Gyr 480 kg average and ruminally cannulated were used. Dry matter offered was adjusted with this equation: 95 g DM (W0.75). A total of 32 nylon bags 10�20 cm, 50±15 micron (Ankom), weighted and identified were introduced in the rumen. Evaluation time was 48 h after bag introduction. Variables evaluated were: ruminal disappearance of Dry Matter, (DM), Neutral Detergent Fiber (NDF) and net energy gain (NEg Mcal kg-1 DM), pH and ruminal temperature. A randomized complete block design, X2 test and Tukey means comparison were performed. Results show that for dry matter, T4 had less residues (30.888a) (p<0.05) in comparison with the other treatments, which didn’t show significant differences. The lowest NDF residues after ruminal degradation was in T3 (57.979�) (p<0.05) with basal diet 2; T1 had the highest values (68.316c). The greatest net energy gain was on T3, being significantly different to control. Results of comparing treatments including Fibrozyme versus control in relation to NDF 48 h after bag introduction show that when adding Fibrozyme, NDF percentages are in general lower than when Fibrozyme was not added. In the same sense, the highest change percentage (15.13%) was when animals were given alfalfa plus. Fibrozyme with basal diet 2. When comparing means of treatments without Fibrozyme versus the ones with it; superiority of these last was of 10.207 % (p<0.01).
J.E. Guerra Liera , E. Ibarra Lopez , L.E. Soto Angulo , J.J.R. Hernandez Moreno , J.L. Corrales Aguirre , J. Rodriguez Garcia , L.A. Lopez Juarez and A. Cordova-Izquierdo , 2007. Alfalfa Ruminal Degradation Using Xylanases. Journal of Animal and Veterinary Advances, 6: 1443-1445.