Caracterización de ensilaje de triticale inoculado con bacterias homolácticas antes del ensilado y expuesto a estrés aeróbico durante el almacenamiento

Abstract

Fresh whole plant spring triticale (x Triticosecale spp.) was field wilted and chopped prior to either being sprayed or not with a homolactic bacterial inoculant (HBI). Wilted triticale was ensiled for 120 d at 20 to 23 °C using 16 PVC mini-silos of 3 L capacity fitted with two-way mechanics to vent gas (which imposed aerobic stress (ASTS) when it remained open), and filled with about 2 kg of the crop containing 35% dry matter (DM) and 5.2% water soluble carbohydrates (WSC) in the DM. Four treatments of a 2x2 factorial were: 1) No HBI/vent closed; 2) HBI/ vent closed; 3) No HBI/vent open; 4) HBI/vent open. Upon opening the mini-silos, chemical composition, fermentation characteristics and in vitro 30 h neutral detergent fiber (NDF) digestibility of the silages were determined. Relative to pre-ensiled forage, either sprayed or not with HBI, ensiling increased (P<0.05) contents of moisture, inorganic matter, fibrous fractions (acid detergent fiber (ADF) and lignin), and ether extract (EE), while decreasing contents of WSC and non-fibrous carbohydrates (NFC). However, treatment had no consistent effect on content of silage nutrients. Of the two non-inoculated silages, the one subjected to ASTS was more than 20 percentage points lower (66 vs. 88 %) in DM recovery (DMR), whereas the HBI silage subjected to ASTS was protected from DM losses. Ensiling and ASTS during the 120 d fermentation decreased NDF digestibility, whereas inoculated non-ASTS silage was nearly as digestible (57.5) as the pre-ensiled forages (58.2 and 60.7%, without and with HBI). Inoculation tended to steer fermentation in a homolactic direction. On balance, HBI is recommended because of the benefits in the fermentation pattern, fiber digestibility and DMR, especially in the presence of ASTS.

Models of Laboratory Mini-Silos to Study the Fermentation of Wilted Alfalfa (Medicago Sativa) Using a Homolactic Bacterial Inoculant

“…Solórzano et al (2016b) achieved packing densities with triticale of approximately 34.7 kg DM/m 3 whereas in the present study we achieved densities >154 kg DM/m 3 using the same type of mini-silo. We agree with the conclusion reached by Solórzano et al (2016a) that treatment differences in fermentation characteristics due to inoculation have a greater opportunity to be expressed in stressed silages, or in this case, lower density packed mini-silos compared with mini-silos packed with a high density that are more conductive to proper and efficient fermentation. By contrast, the mini-silo…”