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Effects of 3 commercial lactic acid bacteria (LAB) inoculants and 6 single strains of LAB on fermentation and levels of aflatoxins and other mycotoxins in high-moisture corn (HMC) silage were examined. Corn plants were inoculated with Aspergillus flavus at silk emergence and wet corn kernels were harvested at black layer stage (dry matter [DM]: 704 ± 5.0 g/kg). Samples were ground and ensiled directly (control group, CTR) or after treatment with one of the 9 LAB inoculants. The commercial inoculants contained Lentilactobacillus (Lent.) buchneri LB1819 and Lactococcus lactis O224 (SiloSolve FC; Chr. Hansen A/S, Hørsholm, Denmark), applied at a final dose of 250,000 CFU/g or 1,250,000 CFU/g (SiloSolve FC 1x and SiloSolve FC 5x , respectively); and Lent. buchneri and Lactiplantibacillus (Lac.) plantarum (Pioneer brand 11B91, Pioneer Hi-Bred International, Des Moines, USA) applied at a final dose of 250,000 CFU/g. One pure strain of Levilactobacillus (Lev.) brevis DSMZ 20054, two pure strains of Lac. plantarum (LP ATCC 8014 and LP PB) and three of Lacticaseibacillus (La.) rhamnosus (LR ATCC 7469, LR LR7 and LR RI) were also applied at a final expected dose of 250,000 CFU/g. Wet corn kernels were ensiled in 20 L mini-silos, compacted to a density of 389 kg DM/m3, and stored at room temperature. Conditions before ensiling were pH 5.87 ± 0.169, and (log 10 CFU/g) of 7.68 ± 0.473 for LAB, 5.71 ± 0.121 for molds and 6.81 ± 0.341 for yeasts. The mini-silos were opened after 30 or 120 days. From day 30–120 days, levels of acetic acid, propionic acid and 1,2 propanediol increased (P < 0.05) in the SiloSolve FC 1x , SiloSolveFC 5x and Pioneer 11B91, and in LR LR7 groups. During this time, butyric acid level increased 5-fold in CTR; by two to three-fold in pure strains groups; and only slightly in the three commercial inoculants and the LR LR7 (P < 0.05). Aerobic stability increased (P < 0.05) with storage time from 32 to 97 h, and the commercial inoculants and LR LR7 groups had longer stability than CTR (P < 0.05). The storage time and the inoculants did not affect aflatoxin levels. No zearalenone or tenuazonic acid were detected in the mini-silos, even if they contaminated the corn plants. Results indicate that different silage inoculants affected fermentation of HMC and its contamination by mycotoxins, although no inoculant had an effect on levels of aflatoxins. • Lactic acid bacteria slightly modified silage mycotoxin contamination. • Aerobic stability improved with commercial inoculants and L. rhamnosus LR7. • The acetic acid and 1,2 propanediol increased with L. buchneri. • Some mycotoxins detected in harvested crop were not quantified at minisilos opening. [ABSTRACT FROM AUTHOR]

• Commercial or pure LAB inoculants slightly modified silage fermentation profile. • Aerobic stability improved with SiloSolve FC and L. rhamnosus ATCC 7469. • The AFB1 concentrations decreased with L. rhamnosus LR7 or L. plantarum ATCC 8014. • The incidence of different mycotoxins changed by use of bacterial inoculants. Effects of commercial and pure lactic acid bacteria (LAB) inoculants on fermentation and levels of aflatoxins and other mycotoxins in corn silage that was experimentally contaminated in the field with a toxigenic strain of Aspergillus flavus (ITEM 8069) were determined. Late-season corn hybrid plants were inoculated with A. flavus at silk emergence, and fresh-chopped corn was harvested at the ⅔ milk line stage (dry matter [DM]: 428 ± 6.5 g/kg) and ensiled directly (control, CTR) or after treatment with 9 LAB inoculants. Commercial inoculants contained Lactobacillus (L.) buchneri LB1819 and Lactococcus lactis O224 or Enterococcus faecium, Lactobacillus plantarum, Lactococcus lactis SR3.54 (respectively SiloSolve FC or SiloSolve MC, Chr. Hansen A/S, Hørsholm, Denmark), L. buchneri and L. plantarum (Pioneer brand 11C33, Pioneer Hi-Bred International, Des Moines, USA). One pure strain of L. brevis DSMZ 20054, two pure strains of L. plantarum (LP ATCC 8014 and LP PB) and three of L. rhamnosus (LR ATCC 7469, LR LR7 and LR RI) were also used. Each silage received an inoculant at final expected dose of approximately 250,000 CFU/g of freshly chopped forage, and was ensiled in 20 L mini-silos, compacted to density of 160 kg dry-mass/m3, stored at room temperature, and opened after 30 or 120 days. The commercial and pure inoculants had few effects on fermentation relative to CTR. Ensiling time and LAB treatment had no effect on silage pH. However SiloSolve FC silage had lower ethanol levels than CTR group, while 1,2 propanediol level doubled as ensiling time increased and the high values were with SiloSolve FC and Pioneer CFT. Aerobic stability increased with ensiling time, with the longest stability in SiloSolve FC and L. rhamnosus ATCC 7469 silage. Lowest aflatoxin B1 (AFB1) concentrations were in the L. rhamnosus LR7 and L. plantarum ATCC 8014 silages (about 8–10 μg/kg DM) and the highest concentration was in L. brevis DSMZ 20054 silage (34.2 μg/kg DM). Concluding, future investigations should be carried out to examine the relationship between LAB and mycotoxinegic fungi during ensiling. [ABSTRACT FROM AUTHOR]