The Effects of a Heterofermentative Lactic Acid Bacterial Inoculant Containing Lentilactobacillus hilgardii and Lentilactobacillus buchneri with or Without Chitinases on the Ensiling, Aerobic Stability, and In Vitro Ruminal Fermentation of Whole-Crop Corn Silages

The objectives of this study were to evaluate the effects of a heterofermentative lactic acid bacterial (LAB) inoculant containing Lentilactobacillus hilgardii and Lentilactobacillus buchneri with or without chitinases on ensiling, aerobic stability (AS), and in vitro ruminal fermentation of whole-crop corn silages. Uninoculated corn silage (Control, C), corn silage treated with chitinase alone (E), with a mixture of L. hilgardii and L. buchneri (I), or with a combination of E and I (EI) were ensiled in minisilos for 90 d, and the terminal silages were assessed for AS and in vitro ruminal fermentation. The experiment used a completely randomized design, with the treatment structure allowing analysis of the effects of E, I, and the E × I interaction. I and EI had higher (p < 0.01) concentrations of acetate and total volatile fatty acids, higher (p < 0.01) total bacterial and LAB counts, but lower yeast population (p < 0.01) than C and E terminal silages. Aerobic stability was greater (p < 0.001) for I and EI (>336 h) than for E (156 h) and C (152 h) silages. LAB reduced (p < 0.001) while chitinase increased (p < 0.05) total in vitro gas production. Disappearance of neutral detergent fiber was lower (p < 0.05) after 6 and 12 h but higher (p < 0.001) after 24 (74.7 and 76.7% vs. 72.7 and 72.3%) and 48 h (84.9 and 86.2% vs. 82.9 and 80.2%) of incubation for I and EI than for C and E, respectively. Inoculation of a mixture of L. hilgardii and L. buchneri alone (I) and in combination with chitinase (EI), but not chitinase (E) alone, enhanced AS and improved the in vitro NDF digestibility of corn silages.