Abstract #86
Section: Forages and Pastures (orals)
Session: Forages and Pastures 1
Format: Oral
Day/Time: Monday 10:45 AM–11:00 AM
Location: Room 233
Session: Forages and Pastures 1
Format: Oral
Day/Time: Monday 10:45 AM–11:00 AM
Location: Room 233
# 86
Effect of a dual-purpose bacterial inoculant and recombinant bacterial expansin-like protein on fermentation profile and digestibility of whole-plant corn silage.
A. A. Pech-Cervantes*1, S. Ramirez2, K. G. Arriola1, E. M. Paula1, C. Heinzen Jr.1, F. X. Amaro1, Y. Jiang1, C. F. Gonzalez3, D. Vyas1, L. F. Ferraretto1, A. T. Adesogan1, 1Department of Animal Sciences, University of Florida, Gainesville, FL, 2Instituto de Ciencias Agropecuarias, Universidad del Papaloapan, Oaxaca, Mexico, 3Department of Microbiology and Cell Science, University of Florida, Gainesville, FL.
Key Words: corn silage, expansin, inoculant
Effect of a dual-purpose bacterial inoculant and recombinant bacterial expansin-like protein on fermentation profile and digestibility of whole-plant corn silage.
A. A. Pech-Cervantes*1, S. Ramirez2, K. G. Arriola1, E. M. Paula1, C. Heinzen Jr.1, F. X. Amaro1, Y. Jiang1, C. F. Gonzalez3, D. Vyas1, L. F. Ferraretto1, A. T. Adesogan1, 1Department of Animal Sciences, University of Florida, Gainesville, FL, 2Instituto de Ciencias Agropecuarias, Universidad del Papaloapan, Oaxaca, Mexico, 3Department of Microbiology and Cell Science, University of Florida, Gainesville, FL.
This study aimed to examine the effects of a dual-purpose bacterial inoculant (DPI) and a recombinant bacterial expansin-like protein (BsEXLX1) on whole-plant corn silage fermentation and digestibility. The dose of BsEXLX1 was estimated based on endoglucanase (2410 μmol/min/ml) and xylanase (16887 μmol/min/ml) activities in the inoculant. The hydrolytic capacity of DPI and freshly purified BsEXLX1 was examined using filter paper (FP) and oat-spell xylan using 4 treatments: 1) Control (Distilled water), 2) BsEXLX1 (37 mg/g), 3) DPI (120,000 cfu/g of lactic acid bacteria and Propionibacterium freudenreichii + fibrolytic enzymes) and 4) DPI + BsEXLX1. In addition, whole-plant corn was harvested at 34% DM, ensiled in quadruplicate for 0, 3 and 60 d in 0.7 kg mini-silos after it was sprayed with or without the treatments. Samples were analyzed for fermentation profile and incubated in quadruplicate to determine 24 h gas production (GP) and in vitro true DM and NDF digestibility. Hydrolytic capacity data were analyzed with a model that included effects of DPI, BsEXLX1 and the interaction, whereas for corn silage samples, the model included effects of DPI, BsEXLX1, day and interactions. Although, DPI and BsEXLX1 synergistically increased (P < 0.01) hydrolysis of FP (7.1 vs 5.5 mg/g), BsEXLX1 decreased hydrolysis of xylan compared with DPI alone (10.3 vs 12.2 mg/g). After 3 d of ensiling, no treatment effects were observed on silage DM, DM recovery, CP concentration or yeast and mold counts (P > 0.10) but BsEXLX1 decreased pH (3.94 vs 3.88, P < 0.01), compared with the Control. After 60 d, lactate concentrations were increased (6.3 vs 8.3% DM, P < 0.05) by DPI, whereas BsEXLX1 decreased NDF concentration (47.1 vs 45.1%, P = 0.03). Consequently, compared with DPI alone, BsEXLX1 and DPI increased starch concentration (20.4 vs 24.9% DM) and tended to increase (P < 0.07) GP (66.2 vs 70.2 mL/g OM), and DMD (48.2 vs 50.2%) but not NDFD (29.6 vs 31.9%) at 60 d. These results suggest that BsEXLX1 + DPI could increase fermentation and digestibility of whole-plant corn silage.
Key Words: corn silage, expansin, inoculant
