Effect of pick-up height during merging and microbial inoculation on the fermentation profile of alfalfa silage at different storage lengths

Abstract

This experiment evaluated the effects of pick-up height during merging and microbial inoculation on fermentation profile of alfalfa silage at different storage lengths. This experiment was a randomized complete block design with a 2 (pick-up height during merging) × 3 (microbial inoculation) × 4 (storage length) factorial arrangement of treatments. Forage from four different blocks (locations) was merged into windrows at a pick-up height of 0 cm (LO) or 6 cm (HI). Then, forage was inoculated with one of two microbial inoculants or control: (1) 150,000 CFU/g of fresh forage of Lactiplantibacillus plantarum DSM26571, Lactococcus lactis NCIMB30117, and Enterococcus lactis DSM22502 (LPEL; SiloSolve® MC, Novonesis, Lingby, Denmark), (2) 150,000 CFU/g of fresh forage of Lactococcus lactis DSM22501 and Lentilactobacillus buchneri DSM11037 (LB; SiloSolve® FC, Novonesis, Lingby, Denmark), or (3) distilled water (CON). Forage was randomly assigned to 7, 14, 28, or 90 d of storage. Data were analyzed using fixed effects of pick-up height during merging, microbial inoculation, and storage length, while block was a random effect. Three-way interactions were observed for pH, lactic acid, and acetic acid. Alfalfa silage pH was lower for LPEL but was greater for HI silage. Lactic acid concentration was greater in LO silage and LPEL treatments, while acetic acid concentration was lower in LPEL and also greater for LO treatments. An interaction between microbial inoculation and storage length was observed for DM losses, which were lower for LPEL by 90 d of storage. Using a homofermentative microbial inoculant improved alfalfa silage fermentation and reduced storage losses, while pick-up height had little effect on fermentation.