Re-ensiling of previously ensiled forage has been a common practice in Brazil, and the use of inoculants may provide a means of reducing dry-matter (DM) loss. This study aimed to determine the effect of reensiling and the use of microbial inoculants on the quality of sorghum silage. Treatments were presence/ absence of an inoculant (Lactobacillus plantarum and Propionibacterium acidipropionici) in the silage, and the re-ensiling, or not, of the material after 24 h of exposure to air, and these were tested in a factorial 2 9 2 design. Losses due to gas, effluent and total DM were assessed, as were the fermentation characteristics, chemical composition, aerobic stability, and aerobic counts of microorganisms. Effluent loss was higher in re-ensiled silage, and these silages had lower lactic acid content and higher levels of acetic and propionic acids. The in vitro DM digestibility was lower in the reensiled sorghum silages. The re-ensiled silage had higher aerobic stability. The inoculant only increased the acetic acid content of the silage. The re-ensiling of sorghum silage increased effluent loss by 71Á2%, and reduced DM digestibility by 5Á35%. The use of inoculant did not influence the quality of sorghum silage.

No abstract

The commercialization of silage in many countries, including Brazil, has increased in recent years. Re-ensiling of previously ensiled forage occurs when silage is relocated from one farm to another, where it will be compacted and sealed again. During this process, silage is exposed to oxygen before being ensiled, which may affect its quality. We exposed sorghum silage to air during the anaerobic storage phase to simulate the transportation of silages between farms. Experimental treatments included silage exposed to air for 0 or 12 h, with or without the use of an inoculant containing a mixture of Lactobacillus plantarum and the propionic bacteria Propionibacterium acidipropionici (1 × 10 cfu/g of forage; Biomax corn, Lallemand, Saint-Simon, France), totaling 4 treatments: conventional silage, conventional silage with inoculant use, re-ensilage after exposure to air, and re-ensilage after exposure to air with use of an inoculant. The sorghum was stored in experimental silos containing about 9.0 kg of fresh forage per replicate. Treatments were tested in a factorial 2 × 2 design with 5 replicates each. Chemical composition, in vitro dry matter digestibility, fermentative characteristics, losses (due to gas, effluents, and total dry matter), microorganism counts, and aerobic stability of sorghum silage were evaluated. Dry matter content of sorghum before ensiling was 273.12 g/kg. The 12-h re-ensiling process increased the effluent loss of the silage when compared with conventional silage (456.42 vs. 201.19 g/kg of FM, respectively). In addition, re-ensiled silages presented lower concentrations of lactic acid and higher concentrations of propionic acid than the silages that had not been opened during storage. The aerobic stability of silage was not affected by the re-ensiling process and the use of inoculant. The use of inoculant increased the pH and loss of dry matter of the silages (4.23 vs. 3.98 and 14.05 vs. 7.82%, respectively) and therefore did not provide any benefits in this study.

The objective of this work was to evaluate the effects of re-ensiling and bacterial inoculation on the quality of corn silage. The experiment was carried out in a 2x2 factorial design with or without inoculant (association of Lactobacillus plantarum and Propionibacterium acidipropionici), and with re-ensiling after 36 hours of aerobic exposure or only ensiling of the whole plant of 'BRS 1055' corn. The fermentative quality, nutritional parameters, dry matter losses, aerobic stability, and microbiological counts of silages were evaluated. Re-ensiling caused an increase of pH and in acetic acid and propionic acid concentrations, as well as in the dry matter (DM), crude protein, neutral detergent fiber, and neutral detergent fiber crude protein contents. Conversely, there was a reduction in the nonfiber carbohydrates concentration and in in vitro dry matter digestibility for the re-ensiled material. All changes were explained by the higher-effluent production and DM loss of re-ensiled material that was subjected to two compactions. Microbiology was not altered by the treatments. The use of inoculant altered ash content, but it did not influence other parameters. In contrast, re-ensiling after 36 hours of aerobic exposure caused a reduction in the nutritive value of corn silage and accentuated the DM losses.

The objective of this work was to determine the effects of sealing delay for 12 hours and of the use of microbial inoculant with heterofermentative bacteria on whole-plant corn (Zea mays) silage. The experimental design was completely randomized in a 2×2 factorial arrangement (with or without inoculant × with or without sealing delay). Silage was evaluated for: chemical composition in vitro dry matter digestibility (IVDMD), fermentative parameters, losses, aerobic stability, and microbiological profile. The heating of the silage caused by respiration increased the contents of neutral detergent insoluble protein and of acid detergent insoluble protein by 77 and 27.3%, respectively. Soluble carbohydrate losses increased the contents of neutral detergent fiber corrected for ash and protein by 9.1% and of acid detergent fiber by 5.1%, but decreased the content of nonfibrous carbohydrates by 11.2%. IVDMD did not differ between treatments. Silages with delayed sealing and the inoculant showed higher pH and contents of acetic acid, propionic acid, and ammoniacal nitrogen, but a lower content of lactic acid. Delayed sealing reduces the nutritional value, increases the fibrous fractions, and decreases the soluble carbohydrates, whereas the use of inoculant does not improve the nutritional value and aerobic stability of the silages.