Caracterização da fermentação e deterioração aeróbia de silagens de planta inteira de milho inoculada com cepa epifítica de Lentilactobacillus farraginis

Abstract

With the objective of evaluating the inoculation of epiphytic lactic acid bacteria (LAB) strains in whole-plant corn silage, two studies were conducted. In the first study, the effects of inoculation with Lentilactobacillus farraginis (LF), Lentilactobacillus hilgardii (LH – CCMA 0170), and Lactiplantibacillus plantarum (LP), applied individually or in coculture, on the fermentative characteristics and aerobic stability of corn silage were evaluated at two storage periods (15 and 68 days). The added inoculants were: control (without inoculant), LF, LH, LF+LH, and LF+LH+LP. Inoculation with LF and with the LF+LH+LP combination resulted in lower dry matter (DM) losses during fermentation. All inoculated silages showed higher concentrations of 1,2-propanediol and greater LAB populations. In addition, the treated silages exhibited greater aerobic stability, characterized by a longer time to reach maximum temperature and a lower maximum temperature, in both storage periods compared with the control. During the aerobic stability evaluation, the LF and LF+LH+LP treatments showed lower DM losses. The results indicate that inoculation with heterofermentative strains, especially L. farraginis in combination with other lactic acid bacteria, promotes better preservation of corn silage, prolongs aerobic stability, and reduces DM losses. In the second study, the effect of the epiphytic strain Lentilactobacillus farraginis on chemical composition, fermentative characteristics, mycotoxin production, and aerobic stability of whole-plant corn silage produced in farm-scale surface silos was evaluated. Two silos were prepared for each treatment (control and LF), opened after 14 days of storage, with a withdrawal rate of ~20 cm/day and sampled at 14, 21, 28, and 35 days. Inoculation reduced DM losses, increased acetic acid concentration and LAB population, and reduced ethanol concentration. Smaller yeast populations were observed in the inoculated silages in most of the evaluated periods. Control silages showed higher concentrations of deoxynivalenol (DON), whereas inoculation numerically reduced this mycotoxin at 14 and 35 days. The inoculated silages exhibited lower heating and a longer time to reach maximum temperature, indicating greater aerobic stability. It is concluded that inoculation with L. farraginis improves fermentative quality, reduces DM losses, increases aerobic stability, and contributes to reducing DON concentration in corn silages.