Aerobic Stability Of Corn Silage Research Articles

Effects of feeding an inoculated corn silage with or without a direct-fed microbial on dry matter intake, milk production, and nutrient digestibility of high-producing lactating Holstein cows.

This study evaluated the effects of inoculating corn silage and/or feeding a direct-fed microbial (PRO) on performance and nutrient digestibility of lactating dairy cows. At harvesting, corn silage was treated either with water (culated or not [CON]) or Lactococcus lactis and Lentilactobacillus buchneri (INC; SiloSolve FC) at 1.5 × 105 cfu/g of corn silage. Ten mini silos and one farm-scale silo bunker per treatment were prepared for the laboratory and the lactating dairy cow trial, respectively. Five mini silos per treatment were opened on days 2 or 90 post-ensiling for pH measurement, as well as chemical analysis and aerobic stability, respectively. The farm-scale silo bunkers were opened 77 d post-ensiling for the beginning of the lactating cow trial. Eighty lactating Holstein cows were assigned in a 2 × 2 factorial design to: (1) CON silage without PRO (CON-CON; n = 20), (2) CON silage with PRO at 14g/head/d (CON-PRO; n = 20), (3) INC silage without PRO (INC-CON; n = 20), and (4) INC silage with PRO at 14g/head/d (INC-PRO; n = 20). Concurrently with the feeding trial, eight cows per treatment were chosen for nutrient digestibility. The pH of the corn silage was not affected by the silage inoculant (P ≥ 0.29), but INC yielded greater concentration of acetic acid and longer aerobic stability (P < 0.01). Dairy cows fed INC had a lower mean total dry matter intake (DMI), milk protein content, and somatic cell counts vs. CON (P ≤ 0.02). On the other hand, milk and fat- and protein-corrected milk (FPCM) production efficiency, milk urea-N, DM, crude protein, and starch digestibility were greater for INC-fed cows (P ≤ 0.03). Feeding direct-fed microbials (DFM) improved mean body weight, milk yield, and FPCM, as well as milk protein and lactose yield (P ≤ 0.05), but reduced milk fat and protein content (P = 0.02). A silage inoculant × DFM interaction was observed for milk production efficiency, milk protein and lactose content, and somatic cell count (P ≤ 0.05). Dairy cows fed INC-CON had a greater milk production efficiency and milk lactose content (P ≤ 0.04), but INC-PRO had lower milk protein content and SCC (P ≤ 0.03). In summary, inoculating L. lactis and L. buchneri increased acetic acid content and aerobic stability of corn silage, reduced DMI, but improved milk production efficiency and nutrient digestibility of lactating Holstein dairy cows. On the other hand, feeding PRO improved milk, protein, and lactose yield. Additionally, combining the feeding of an inoculated corn silage with PRO reduced milk somatic cell count.

Придание аэробной стабильности кукурузному силосу при химическом консервировании

Aerobic stability of corn silage, as well as other types of silage, can be achieved by chemical preservation. Currently, mainly organic acids and their salts are used as chemical preservatives. The highest preservative effect is provided by undissociated forms of acids. Dissociation occurs most intensely in a reaction environment close to neutral and is significantly inhibited in an acidic environment. To give silage aerobic stability, the chemical preservative must have fungicidal and static properties, since the main initiators of aerobic decomposition are yeast. Of the organic acids, propionic acid has such properties to the highest extent, and acetic acid to a somewhat lesser extent. Other representatives of organic acids with fungicidal properties not inferior to propionic acid are benzoic, sorbic, acrylic and others. Salts of these acids also have similar properties. The use of mixtures of acids and salts significantly enhances their preservative effect, provided that their components interact synergistically. In addition to these mixtures, the fungicidal effect of a mixture of monoglycerides: monopropionate and monobutyrate has recently been established. Unlike biological products, the fungicidal effect of chemical preservatives manifests itself from the first days of use.

Optimizing corn silage quality during hot summer conditions of the tropics: investigating the effect of additives on in-silo fermentation characteristics, nutrient profiles, digestibility and post-ensiling stability

Corn crop grown and ensiled at high temperature have lower water soluble carbohydrates (WSC), epiphytic lactic acid bacteria (LAB) population, lactic acid concentration, fermentation quality and aerobic stability. This study systematically investigated the effects of heterofermentative LAB (hetLAB), homofermentative LAB (homLAB), molasses and their mixture (MIX) on in-silo fermentation characteristics, chemical profiles, Cornell Net Carbohydrate and Protein System (CNCPS) carbohydrate subfractions, in vitro digestibility (DMD), microbial count, and post-ensiling aerobic stability of whole crop corn silage during hot summer (30 to 45°C) condition. Corn hybrids (P30K08 and DK6789) were ensiled at targeted dry matter (DM) of 330 g/kg for 0, 3, 7, 21, and 150 days in 3 L silos, without additive (CCS) or treated with hetLAB (4×106 cfu/g Lactobacillus buchneri), homLAB (1×106 cfu/g of L. plantarum), molasses (3% of fresh forage) or MIX (half of individual doses of homLAB, hetLAB and molasses) additives. The CCS, homLAB, hetLAB, molasses, or MIX treated chopped material of each hybrid were ensiled in 16 replicate silos at a density of 260 kg of DM/m3. Compared to CCS, the additives significantly improved silage nutritional and fermentation quality, DM digestibility (in vitro), count of LAB, DM recovery and aerobic stability, and decreased counts of yeast and mold. Among the inoculants, the homLAB and MIX inoculated silages had greatest improvement in fermentation quality and nutritional value. The homLAB produced corn silage with the highest (P &amp;lt; 0.05) content of lactic acid, and soluble carbohydrates, and lowest contents of acetic acid, NH3-N and pH, demonstrating desirable and restricted in silo fermentation. On the other hand, the hetLAB inoculated silages had the greatest (P &amp;lt; 0.05) value of acetic acids, highlighting greater aerobic stability. Interestingly, the MIX silages followed the hetLAB in acetic acid value and homLAB in lactic acid value. Notably, without additive stable pH was not achieved during 21 days, with application of molasses, hetLAB and the MIX inoculants stable pH was achieved during 7 days, and with homLAB stable pH was achieved during the first 3 days of ensiling. The greatest numbers of viable LAB were recorded in homLAB (8.13 log cfu/g) and MIX (7.89 log cfu/g) inoculated silages, while the lowest for CCS (6.29 log cfu/g). The lowest yeast (1.48 log cfu/g) and mold (0.22 log cfu/g) were recorded for hetLAB inoculated silage. The greatest (P &amp;lt; 0.05) DM recovery was recorded for hetLAB (97.3%) and MIX (96.9%), and the lowest for the control silage (92.9%). All additives significantly improved the aerobic stability of corn silage, and the greatest value of &amp;gt;72 h was recorded for hetLAB and MIX inoculats, and the lowest for CSC (25 h). In conclusion, additives application can improve fermentation quality, nutritional value, DM recovery and aerobic stability of whole crop corn silage under hot summer conditions of the tropics. The MIX inoculant showed potential to improve in-silo fermentation, and aerobic stability at the same time, however, further investigation are required, particularly with respect of dose rate.

Feed intake, digestibility, ruminal fermentation, growth performance, and carcass traits of lambs fed corn silage treated with Lentilactobacillus buchneri and stored for different times

Our objective was to investigate the impact of inoculation and storage length of flint corn silage on the metabolic and production responses of lambs. A flint corn hybrid was harvested with 315 g dry matter (DM)/kg and ensiled in concrete pipe silos without (control) or with Lentilactobacillus buchneri CNCM I-4323 at 1 × 105 cfu/g of fresh forage for 120, 240 and 360 d (n = 2 for each treatment). Such silages were used to formulate six different diets. Sixty non-castrated male Dorper × Santa Inês lambs were used in the feeding program (n = 10). Additionally, eight ruminally cannulated Dorper × Santa Inês crossbred lambs were used to measure the ruminal fermentation (n = 4). Extending the storage of corn silage from 120 to 360 d increased the contents of soluble protein (P = 0.030; 415–490 g/kg CP) and ammonia-N (P = 0.047; 82.5–114 g/kg total N). Compared to the control, inoculation resulted in higher (P < 0.05) concentration of lactic (+19.9 %) and acetic acid (+38.6 %), and lower butyric acid (–25.3 %), ammonia-N (–23.5 %), and DM loss (–36.2 %). The aerobic stability of corn silage was also improved by inoculation (P = 0.002; +160 h compared to the control). An interaction between storage length and inoculation was reported for feed intake, and lambs had increased DMI (P < 0.001) by feeding the inoculated silage stored for 120 d. Overall, the total-tract starch digestibility increased (P = 0.041) with longer storage (120 d = 94.4 %; 240 d = 95.7 %; 360 d = 96.5 %). However, the total VFA was unchanged (P > 0.05) while the ruminal molar proportion of propionate decreased from 22.8 to 20.7 mM/100 mM in lambs fed corn silage stored for 120 and 360 d (P = 0.004). Lengthening silage storage from 120 to 240 and 360 d tended (P = 0.06) to increase the ADG of lambs by 4.6 % and 10.2 %, respectively (120 d = 0.216 kg/d; 240 d = 0.226 kg/d; 360 d = 0.238 kg/d). Moreover, the feed efficiency was substantially improved (P = 0.008) by 5 % and 14 % when the silages were stored for 240 and 360 d compared to 120 d. In opposite, inoculation had no effect (P > 0.05) on ADG and feed efficiency of lambs. Final hot carcass weight (data ranged from 16.8 to 17.2 kg) and 12th rib longissimus muscle area (data ranged from 13.8 to 14.7 cm2) were not affected by treatments (P > 0.05). Overall, only few parameters of carcass and meat traits of lambs were altered by storage length and inoculation, but it were of minor biological importance. In conclusion, the productivity responses of lambs were enhanced by increasing the storage length of flint corn silage, but inoculation with L. buchneri did not contribute to improve animal performance.

Dominance of bacillus sp. alter microbiological and nutritional quality and improve aerobic stability of the corn silage

The objective of this study was to evaluate the impacts of L. plantarum, L. brevis, and E. faecium on microbiological and nutritional profiling and aerobic stability of corn silage. For this purpose, corn fodder was chopped and ensiled with a dry matter (DM) content of 27–30%. An inoculum consisting of Lactobacillus plantarum IFA 96 (DSM 19456), Enterococcus faecium B1034 (DSM3530), Lactobacillus brevis IFA 92 (D5119456) mix culture was added at rate of 2, 4, and 6 g/ton. The fermentation was carried out at ambient temperature in polythene bags under anaerobic condition for 45 days. It was found that the 4 g/ton microbial inoculant in the corn silages have significant impacts on silage nutritive values in terms of (p < 0.05) higher pH, dry matter, and organic matter contents, while decreasing the fiber contents. This could be related to the unique combination of microbiota present in the inoculum. The total bacterial counts and yeasts were significantly (p < 0.05) increased with increase in the concentration of inoculant while Lactobacillus count was (p < 0.05) increased with increase in 4 g/ton inoculate level. Mostly silages samples were positive for Aspergillus flavus, Listeria monocytogenes, and coliform expect the silage treated with 4 g/ton microbial inoculants. The results showed that silages inoculated with 4 g/ton showed improved nutritive and fermentative characteristics and higher aerobic stability of the corn silage.

Lentilactobacillus buchneri Preactivation Affects the Mitigation of Methane Emission in Corn Silage Treated with or without Urea

The aim of this study was to investigate the effect of different forms of Lentilactobacillus buchneri on the in vitro methane production, fermentation characteristics, nutritional quality, and aerobic stability of corn silage treated with or without urea. The following treatments were applied prior to ensiling: (1) no urea treatment and LB; (2) no urea treatment+freeze dried LB; (3) no urea treatment+preactivated LB; (4) with urea treatment+no LB; (5) with urea treatment+freeze dried LB; (6) with urea treatment+preactivated. LB was applied at a rate of 3 × 108 cfu/kg on a fresh basis, while urea was applied at a rate of 1% on the basis of dry matter. Data measured at different time points were analyzed according to a completely randomized design, with a 2 × 3 × 5 factorial arrangement of treatments, while the others were analyzed with a 2 × 3 factorial arrangement. Preactivated LB was more effective than freeze-dried LB in reducing silage pH, ammonia nitrogen, cell-wall components, yeast count, and carbon dioxide production, as well as increasing lactic acid and residual water-soluble carbohydrate and aerobic stability (p &lt; 0.0001). A significant reduction in the methane ratio was observed after 24 h and 48 h incubation with preactivated forms of LB (p &lt; 0.001). The results indicated that preactivated LB combined with urea improved fermentation characteristics, nutritional quality, and aerobic stability and reduced the methane ratio of corn silages.

Effects of bacterial inoculants on the microbial community, mycotoxin contamination, and aerobic stability of corn silage infected in the field by toxigenic fungi

This study aimed to evaluate the effects of inoculants on the microbial community and mycotoxins contamination of corn silage during aerobic exposure. Whole-crop corn infected with or without mycotoxigenic fungi were ensiled with Lentilactobacillus buchneri (LB, 1.0 × 106 cfu/g fresh weight (FW)), Lactiplantibacillus plantarum (LP, 1.0 × 106 cfu/g FW), or LBLP at 1.0 × 106 cfu/g FW each. The concentration of acetic acid (AcA) (P < 0.05) in LB and LBLP silages was higher than in control (C) and LP of non-fungal infection (NFI) silages. The fungal infection resulted in a larger increase of zearalenone (ZEN, P = 0.01), fumonisin B1 (FUB1, P = 0.02), and fumonisin B2 (FUB2, P = 0.02). The relative abundance (RA) of Issatchenkia in NFI was higher (P < 0.001) than FI silages, whereas the RA of Kazachstania (P < 0.001), Zygosaccharomyces (P = 0.047), and Candida (P = 0.025) in NFI were lower than these of FI silages. The aerobic stability was improved by the application of LB and LBLP as compared with the C of NFI silages. The LB and LBLP had the potential to improve aerobic stability and alleviate mycotoxins contamination of non-fungal infected corn silages.Graphical

Effect of dry matter content on the microbial community and on the effectiveness of a microbial inoculant to improve the aerobic stability of corn silage

Silage inoculants are commonly used as a tool to improve the fermentation and aerobic stability of corn silage fed to dairy cows. However, their effectiveness can be inconsistent. Our objective was to determine the effect of the dry matter (DM) content of freshly chopped whole-plant corn on its microbial community as affected by an inoculant containing Lentilactobacillus hilgardii, Lentilactobacillus buchneri, and Pediococcus pentosaceus on improving the aerobic stability of silage. Whole-plant corn was harvested at low (31.80%, LDM), medium (33.32%, MDM), or high (39.44%, HDM) DM content and treated with nothing (CTR) or an inoculant (INO) containing L. hilgardii CNCM I-4785 at 150,000 cfu/g fresh forage, L. buchneri NCIMB 40788 at 150,000 cfu/g fresh forage, P. pentosaceus NCIMB12455 at 100,000 cfu/g of fresh forage, β-glucanase (5,750 IU/g), and xylanase (30,000 IU/g) and ensiled for 20 and 60 d. Data were analyzed as a completely randomized design in a 3-by-2 factorial arrangement of treatments. Fresh LDM forage had a higher concentration of reducing sugars, a less rich, diverse, and even bacterial community, and greater relative abundance of Saccharomycetales than MDM and HDM forages. Silages at 20 and 60 d, inoculated LDM had a more modest proliferation of culturable lactic acid bacteria than inoculated MDM. At 20 d, regardless of treatment, LDM had greater concentrations of lactic and acetic acids. Also at 20 d, LDM had lower numbers of culturable yeasts but greater relative abundance of Enterobacteriaceae than MDM and HDM. For silage at 20 d, HDM silage was more aerobically stable than LDM and MDM and inoculation improved aerobic stability 1.8-fold compared with CTR. For silage at 60 d, there was an interaction between DM content and inoculation. The improvements in stability by inoculation, compared with CTR, were greater in MDM (261 vs. 41 h) and HDM (320 vs. 66 h) silages than in LDM (85 vs. 46 h). The lower DM content and possible slower pH decline in LDM might have facilitated the development of undesirable bacteria and coupled with its greater concentration of reducing sugars and lactic and acetic acids, which are substrates for aerobic microorganisms, might explain the more modest improvements in aerobic stability from inoculation in LDM compared with MDM and HDM. Our findings suggest that the DM content of whole-plant corn affected its epiphytic microbial community and the effectiveness of the inoculant, which improved aerobic stability at all DM but to a greater extent in HDM and MDM than in LDM, especially after 60 d of ensiling.

Effect of Various Strains of Lactobacillus buchneri on the Fermentation Quality and Aerobic Stability of Corn Silage

The aerobic deterioration of silage nutrients is inevitable in tropical countries, causing negative consequences in animal production systems. Aiming to minimize the losses, the effects of Lactobacillus buchneri strains on fermentation profile and aerobic stability of corn silages were evaluated. The experiment was conducted under a completely randomized design with 13 treatments and three replicates. The treatments were noninoculated, commercial L. buchneri (CI), and 11 wild strains of L. buchneri: LB-56.1, LB-56.2, LB-56.4, LB-56.7, LB-56.8, LB-56.9, LB-56.21, LB-56.22, LB-56.25, LB-56.26, and LB-56.27. The treatments could be divided into three different groups according to silage pH and acetic acid concentration. Silages inoculated with LB-56.1, LB-56.4, and LB-56.9 presented higher pH, whereas intermediate values were observed for LB-56.2, LB-56.7, and LB-56.8. The highest acetic acid production was observed for LB-56.1 and LB-56.7. On the other hand, lowest concentrations were found for CI, LB-56.22, LB-56.25, LB-56.26, and LB-56.27. Higher amounts of NH3–N were observed for LB-56.8, LB-56.21, LB-56.22, and LB-56.27 silages than others. Silage inoculation with CI, LB-56.1, LB-56.2, LB-56.4, LB-56.8, LB-56.9, and LB-56.25 strains had higher aerobic stability than others (59.7 vs. 41.2 h). The L. buchneri strains LB-56.1, LB-56.2, LB-56.4, LB-56.8, LB-56.9, and LB-56.25 provided potential features to improve the aerobic stability of corn silage.

Effects of a Dual-Purpose Inoculant on the Quality and Aerobic Stability of Corn Silage at the Laboratory and Field Scales

This study investigated the effects of a dual-purpose inoculant (DPI) on the fermentation profile, nutritive value, and aerobic stability of silage. The inoculant effect was first examined with minisilos, and the results were later validated with 400-kg silo bales and a 40-t bunker silo. Briefly, whole-plant corn harvested at the one-half to two-thirds milk line stage was chopped and then treated with or without inoculant containing Lactobacillus plantarum LP1028 and Lactobacillus buchneri LBC1029 at application rates of 2.5 × 105 cfu and 5.0 × 105 cfu per gram of fresh forage, respectively. The results showed that applying DPI had no effect on the nutritive value in all trials. DPI inoculation also slowed yeast and mold growth in silage under aerobic exposure. Inoculation may double the aerobic stability time after 105 d of ensiling (53.25 vs. 113.20 h) in a bunker silo. This study successfully examined the effectiveness of DPI in minisilos, and the results were consistent when moving from the laboratory to the field. Applying DPI made the fermentation more heterolactic without compromising the silage nutritive value, and increasing acetic acid acted as an antifungal agent to inhibit spoilage microbial growth and improve silage aerobic stability.

The effects of Lactobacillus hilgardii 4785 and Lactobacillus buchneri 40788 on the microbiome, fermentation, and aerobic stability of corn silage ensiled for various times

We evaluated the ability of an inoculant containing a combination of Lactobacillus hilgardii and Lactobacillus buchneri to modify the microbiome and improve the aerobic stability of whole-plant corn silage after various lengths of ensiling. Chopped whole-plant corn at about 33% dry matter (DM) was uninoculated (CTR) or inoculated with L. hilgardii CNCM I-4785 and L. buchneri NCIMB 40788 at 200,000 cfu/g of fresh forage weight each (combined application rate of 400,000 cfu of lactic acid bacteria/g of fresh forage weight; LHLB), L. buchneri NCIMB 40788 at 400,000 cfu/g of fresh forage weight and Pediococcus pentosaceus NCIMB 12455 at 100,000 cfu/g of fresh forage weight, used as a positive control (LB500), L. hilgardii CNCM I-4785 at the application rate used in the LHLB formulation of 200,000 cfu/g of fresh forage weight (LH), or L. buchneri NCIMB 40788 at the application rate used in the LHLB formulation of 200,000 cfu/g of fresh forage weight (LB). Silos were opened after 34 and 99 d of ensiling and analyzed for nutrient composition, fermentation profile, microbiome, and aerobic stability. After 34 d of ensiling, the inoculated silages had greater numbers of culturable lactic acid bacteria, a bacterial community less rich and diverse, greater relative abundance of Lactobacillus, lower relative abundance of Klebsiella, and a greater concentration of propionic acid than uninoculated silages. Inoculation decreased the ratio of lactic acid to acetic acid, except for LB alone. Treatment LHLB resulted in silage with a greater concentration of 1,2-propanediol than LB500 and was the only treatment to have a lower relative abundance of Saccharomycetes compared with uninoculated silage. Treatments LHLB and LB500 improved the aerobic stability compared with CTR, but the individual LH and LB treatments applied at a low dose did not. Whereas LB500 was stable 34 h longer than CTR, LHLB was stable 91 h longer. After 99 d of ensiling, all inoculated silages had markedly greater aerobic stability than uninoculated silage and were stable for more than 360 h. The inoculant containing a combination of L. hilgardii and L. buchneri markedly improved the aerobic stability of corn silage after a relatively short period of ensiling, and such improvements were greater than the ones obtained from inoculation with the combination of L. buchneri and P. pentosaceus. Inoculating with the combination of L. hilgardii and L. buchneri may be helpful to producers that must feed silage shortly after ensiling.

Effect of urea on gas and effluent losses, microbial populations, aerobic stability and chemical compositivo of corn (Zea mays L.) silage

&#x0D; We evaluated the effects of urea addition on gas and effluent losses, fermentation profile, microbial populations, aerobic stability and chemical composition of corn silages. A completely randomised design with five levels of urea (0, 0.5, 1.0, 1.5, and 2.0% based on dry matter) and five replicates was used. A decreasing linear effect of urea levels on effluent losses in corn silages was observed. In parallel, an increasing linear effect of urea levels on pH, increasing from 3.49 to 4.12 in silages without urea in relation to silages with the maximum urea level, was also observed. Urea addition improved the aerobic stability of the silages, with 62 h for the silages without urea and from 90 to &gt;96 h for the silages with urea. Based on the results of the principal components, two groups (I and II) could be distinguished. The most discriminating variables in group I were dry matter (-0.9), pH (-1.2) and lactic acid bacteria (-0.9), while in group II, effluent losses (1.0), ethanol (1.0), acetic acid (0.8) and gas losses (0.8) were most important. The use of urea at inclusion levels of around 2% in corn silage reduced gas losses, improved the nutritive value and promote the aerobic stability of silages.&#x0D; Highlights:&#x0D; &#x0D; The addition of urea in the corn silages increased the pH values from 3.49 (control) to 4.12 (2% of urea DM).&#x0D; The use of urea improved chemical composition of corn silages.&#x0D; The addition of urea reduced the moulds and yeast populations in the corn silages after exposure to air.&#x0D; Urea addition improved the aerobic stability of the corn silages.&#x0D;

Effects of homo- and hetero-fermentative lactic acid bacteria on the quality and aerobic stability of corn silage

This study aimed to investigate the effects of homo/heterofermentative lactic acid bacteria (LAB) on the quality of corn silage and its rumen digestibility. Maize (Zea mays strain Xingsiyu No. 10), at the early dough stage, was harvested, chopped, ensiled in vacuum bags, and divided into four groups: (1) control (without added bacteria); (2) with the homofermentative LAB Lactobacillus plantarum and Pediococcus pentosaceus (1:1 mixture, 1 × 105 cfu·g−1); (3) with the heterofermentative LAB Lactobacillus buchneri (1 × 105 cfu·g−1); and (4) with the homo/heterofermentative LAB L. plantarum, P. pentosaceus, and L. buchneri (1:1:1 mixture). At 2, 8, 15, 45, and 60 d of ensiling, nutritional quality, fermentation characteristics, and microbial content were assessed. After 60 d, aerobic stability and rumen digestibility tests were performed. The addition of homo- and (or) hetero-fermentative LAB significantly improved the nutritional quality, fermentation characteristics, and microbial content. Addition of the heterofermenter L. buchneri, with or without the homofermenters L. plantarum and P. pentosaceus, improved aerobic stability. The different LAB inoculants increased the degradation rates of dry matter, acid detergent fiber, and neutral detergent fiber of the corn silage by sheep ruminants. Analysis indicated that L. buchneri yielded the best corn silage.

Lentilactobacillus hilgardii Inoculum, Dry Matter Contents at Harvest and Length of Conservation Affect Fermentation Characteristics and Aerobic Stability of Corn Silage.

Heterofermentative Lentilactobacillus hilgardii isolated from sugarcane silage, has recently been proposed as a silage inoculant to increase aerobic stability. Various conditions can influence the activity of LAB and their ability to alter silage quality (e.g., DM content and length of conservation). The aim of this study has been to evaluate the effect of L. hilgardii on the fermentation quality and aerobic stability of whole crop corn silage with different DM contents (from 26 to 45%), conserved for various conservation lengths (13–272 days). The silages were analyzed for their DM content, pH, fermentative profile, microbial count, and aerobic stability. L. hilgardii showed a positive effect on improving the aerobic stability of silages, due its ability to produce acetic acid, and reduced the yeast count. The acetic acid content increased as the conservation period increased and decreased as the DM content increased. The yeast count was reduced during conservation in a DM dependent manner and the inoculation with LH determined a reduction in the count of 0.48 log cfu/g. The aerobic stability increased as the conservation period increased, and the treatment with LH on average increased the aerobic stability by 19 h. The results of this experiment suggest that higher aerobic stability could be achieved in corn silages by ensiling at medium or low DM contents, or by increasing the length of conservation if a higher DM content at ensiling is needed. The inoculation with LH helps to improve the aerobic stability of corn silages by reducing the yeast count.

Effects of Bacillus subtilis and its metabolites on corn silage quality.

Cellulolytic micro-organisms are potent silage inoculants that decrease the fibrous content in silage and increase the fibre digestibility and nutritional value of silage. This study aimed to evaluate the effects of Bacillus subtilis CCMA 0087 and its enzyme β-glucosidase on the nutritional value and aerobic stability of corn silage after 30 and 60days of storage. We compared the results among silage without inoculant (SC) and silages inoculated with B. subtilis 8 log10 CFU per kg forage (SB8), 9 log10 CFU per kg forage (SB9) and 9·84 log10 CFU per kg forage + β-glucosidase enzyme (SBE). No differences were observed in the levels of dry matter, crude protein and neutral detergent fibre due to the different treatments or storage times of the silos. Notably, the population of spore-forming bacteria increased in the SB9-treated silage. At 60days of ensiling, the largest populations of lactic acid bacteria were found in silages treated with SB8 and SBE. Yeast populations were low for all silages, irrespective of the different treatments, and the presence of filamentous fungi was observed only in the SBE-treated silage. Among all silage treatments, SB9 treatment resulted in the highest aerobic stability.

The effects of air stress during storage and low packing density on the fermentation and aerobic stability of corn silage inoculated with Lactobacillus buchneri 40788

We determined if a microbial inoculant could improve the fermentation and aerobic stability of corn silage subjected to various challenges during storage that included an air stress challenge and low packing density. In Experiment 1, whole-plant corn was untreated (CTR) or treated (INO, Lactobacillus buchneri 40788 and Pediococcus pentosaceus 12455. Five individually replicated 7.5-L silos, at a density of 240 kg of dry matter (DM)/m3, for each treatment were kept sealed (NAS) for 19 wk, air stressed early (ES, 3 h/wk for wk 1-9), or air stressed late during storage (LS, 3 h/wk for wk 10-19). Inoculation increased the number of agar-culturable lactic acid bacteria regardless of air stress status, but it did not affect the relative abundance of Lactobacillus. Early, but not late air stress, resulted in silages with a higher relative abundance of Acetobacter when compared with NAS. Silages treated with INO had greater concentrations of acetic acid than CTR. Numbers of yeasts were lowest for INO regardless of air stress and CTR-LS had the most yeasts among all treatments. Silages that were not air stressed had a higher relative abundance of Candida tropicalis than air stressed silages. Monascus purpureus was detected in ES and LS but not in NAS, and its relative abundance was numerically higher in CTR-ES than in INO-ES and statistically higher in CTR-LS compared with INO-LS. Early air stress numerically reduced aerobic stability compared with NAS, and there was a statistical tendency for lower stability in LS compared with NAS. Inoculation improved aerobic stability regardless of when the air stress occurred. In Experiment 2, corn silage was prepared with the same primary treatments of CTR and INO but was packed at a low (LD; 180 kg of DM/m3) or a normal (ND; 240 kg of DM/m3) density and sealed (NAS) or air stressed (AS; 24 h on d 28, 42, and 89) for 92 d of storage. The concentration of acetic acid was greater in INO compared with CTR and in AS compared with NAS. Numbers of yeasts were lower in NAS compared with AS regardless of inoculation and they were lower in INO-AS compared with CTR-AS. Treatment with INO improved aerobic stability but the improvement was better in NAS versus AS and better in ND versus LD. Overall, our experiments corroborate past findings showing that INO markedly improves the aerobic stability of corn silage but they are the first to show that improvement can be sustained even when the silage was exposed to regular air stresses and when packed at a low density.

Effect of 11CFT and 11C33 inoculants on the chemical and fermentation composition, and aerobic stability of corn silage during the feed out period

The objective was to evaluate the efficiency of two bacterial inoculants, 11CFT and 11C33, with different genera of lactic acid bacteria on the chemical and fermentation composition of the silage, and the temperature and pH behavior of the silage during the feed out period. The experimental design used was randomized blocks, with three treatments: corn silage without inoculant (control); corn silage with 11CFT inoculant (consisting of strains of Lactobacillus buchneri and L. casei); and corn silage with 11C33 inoculant (consisting of strains of L. buchneri, L. plantarum and Enterococcus faecium). The use of both inoculants increased the concentration of lactic acid in the silage (22.42 g kg-1 for control against 36.00 and 33.33 g kg-1 for 11CFT and 11C33, respectively) and reduced aerobic dry matter losses. The silage treated with 11C33 obtained a higher concentration of acetic acid (17.44 g kg-1) and propionic acid (2.08 g kg-1). The 11CFT inoculant provided a lower concentration of ethanol, however, without differing from the silage with 11C33 (0.70 and 1.61 g kg-1, respectively). Even without variations in temperature and pH at silage unloading, the use of the 11C33 inoculant generated a higher concentration of acetic and propionic acid, providing better aerobic stability days after unloading. Both inoculants also improved the in situ ruminal digestibility of corn silage compared to control silage. They provide an increase in the content of lactic and propionic acids, which assist to reduce dry matter losses and ethanol production. There were no variations in temperature and pH at the silo unloading, however, the use of the 11C33 inoculant generated a higher concentration of acetic and propionic acids providing better aerobic stability after exposure to air.

Temperature during conservation in laboratory silos affects fermentation profile and aerobic stability of corn silage treated with Lactobacillus buchneri, Lactobacillus hilgardii, and their combination

The environment temperature and its effect on the temperature of silage is very important for the fermentation and subsequent quality of a silage. Obligate heterofermentative lactic acid bacteria (LAB) inocula, because of their ability to inhibit yeasts, have been developed to prevent the aerobic deterioration of silages. The temperature during silage conservation may also play an important role in the fermentation profile of silages. This study has evaluated the effect of temperature, during the conservation of whole crop corn silage, untreated or treated with different LAB inocula, on the fermentation profile and on the aerobic stability of the silage. Corn was harvested at 42% dry matter and either not treated (control) or treated with Lactobacillus buchneri NCIMB 40788 (LB) at 300,000 cfu/g fresh matter (FM); Lactobacillus hilgardii CNCM I-4785 at 150,000 cfu/g FM (LH150); L. hilgardii CNCM I-4785 at 300,000 cfu/g FM (LH300); or LB+LH at 150,000 cfu/g FM each. In an attempt to experimentally simulate temperature fluctuations in the mass or at the periphery of a silage bunker, corn was conserved in laboratory silos at a constant temperature (20 ± 1°C; MASS) or at lower and variable outdoor temperatures (PERIPH; ranging from 0.5 to 19°C), and the silos were opened after 15, 30, and 100 d of conservation. Lactic acid, acetic acid, and ethanol contents increased in all the silages over the conservation period. The lactic acid content was higher (+10%) in the silages kept at a constant temperature than those conserved at the lower and variable outdoor temperatures. The acetic acid was higher in the treated silages than in the control ones conserved at a constant temperature for 100 d. Moreover, 1,2-propanediol was only detected in the treated silages after at least 30 d at a constant temperature, whereas only traces were detected in the LB+LH treatment for the other temperature conditions. The yeast count decreased during conservation at a slower rate in PERIPH than in MASS and on average reached 2.96 and 4.71 log cfu/g for MASS and PERIPH, respectively, after 100 d of conservation. The highest aerobic stability values were observed for LH300 (191 h) in the MASS silage after 100 d of conservation, whereas the highest aerobic stability was observed in LB+LH (150 h) in the PERIPH silages. After 7 d of air exposure, a pH higher than 4.5 and a higher yeast than 8.0 log cfu/g were detected in all the silages opened after 15 and 30 d of conservation. A pH value close to that of silo opening was detected in the LB, LH150, and LH300 silages conserved under MASS conditions after 100 d, whereas LB+LH was the most effective under PERIPH conditions. The temperature and its fluctuation during conservation of silage in laboratory silos influenced the fermentation, which in turn had an effect on the quality of silage and on the extent of the effect of LAB inocula.

Effects of inoculation of corn silage with Lactobacillus hilgardii and Lactobacillus buchneri on silage quality, aerobic stability, nutrient digestibility, and growth performance of growing beef cattle.

This study evaluated the effects of inoculation of whole crop corn silage with a mixture of heterofermentative lactic acid bacteria (LAB) composed of Lactobacillus hilgardii and Lactobacillus buchneri on ensiling, aerobic stability, ruminal fermentation, total tract nutrient digestibility, and growth performance of beef cattle. Uninoculated control corn silage (CON) and silage inoculated with 3.0 × 105 cfu g-1 of LAB containing 1.5 × 105 cfu g-1 of L. hilgardii CNCM I-4785 and 1.5 × 105 cfu g-1 of L. buchneri NCIMB 40788 (INOC) were ensiled in silo bags. The pH did not differ (P > 0.05) between the two silages during ensiling but was greater (P < 0.001) for CON than INOC after 14 d of aerobic exposure (AE). Neutral detergent insoluble crude protein (NDICP) content (% of DM and % of CP basis) of terminal INOC silage was greater (P ≤ 0.05) than that of CON. In terminal silage, concentrations of total VFA and acetate were greater (P < 0.001), while water-soluble carbohydrates were lower (P < 0.001) for INOC than CON. Yeast and mold counts were lower for INOC than CON (P ≤ 0.001) in both terminal and aerobically exposed silages. The stability of INOC was greater (P < 0.001) than that of CON after 14 d of AE. Ruminal fermentation parameters and DMI did not differ (P > 0.05) between heifers fed the two silages, while there was a tendency (P ≤ 0.07) for lower CP and starch digestibility for heifers fed INOC than CON. Total nitrogen (N) intake and N retention were lower (P ≤ 0.04) for heifers fed INOC than CON. Dry matter intake as a percentage of BW was lower (P < 0.04) and there was a tendency for improved feed efficieny (G:F; P = 0.07) in steers fed INOC vs. CON silage. The NEm and NEg contents were greater for INOC than CON diets. Results indicate that inoculation with a mixture of L. hilgardii and L. buchneri improved the aerobic stability of corn silage. Improvements in G:F of growing steers fed INOC silage even though the total tract digestibility of CP and starch tended to be lower for heifers fed INOC are likely because the difference in BW and growth requirements of these animals impacted the growth performance and nutrient utilization and a greater proportion of NDICP in INOC than CON.

Effect of Inoculation with Preactivated Lactobacillus Buchneri and Urea on Fermentative Profile, Aerobic Stability and Nutritive Value in Corn Silage

The current study aimed to evaluate the application effects of the preactivated Lactobacillus buchneri and urea on the fermentative characteristics, chemical composition and aerobic stability in corn silages. The design was completely randomized, in a 6 × 5 factorial arrangement, with six types of additive and five opening times. The treatments consisted of corn silage; corn silage with freeze-dried inoculant; corn silage with freeze-dried inoculant +1.0% urea; corn silage with activated inoculant; corn silage with activated inoculant +1.0% urea, and corn silage with 1.0% urea. Populations of lactic acid bacteria stabilized at the 70th day, with average values of 8.91 and 9.15 log cfu/g for corn silage with freeze-dried inoculant +1.0% urea and corn silage with freeze-dried inoculant, respectively. In contrast, the silages without additives showed significantly lower values of 7.52 log cfu/g forage at the 70th day. The silages with urea (isolated or associated with the inoculant) increased the total nitrogen content. The maximum temperature values were highest in the corn silages without additives, indicating that these silages were more prone to deterioration. The use of Lactobacillus buchneri activated proved to be more efficient in improving the fermentative profile of corn silages than the freeze-dried inoculant. The use of urea as an additive reduced the losses and improved the nutritional value and aerobic stability of corn silages. Additionally, the combination of Lactobacillus buchneri activated and urea may be used as a technique to improve the fermentative profile, chemical composition and aerobic stability of corn silages.