Ensiling Of Corn Research Articles

Storage Temperature Is More Effective Than Lactic Acid Bacteria Inoculations in Manipulating Fermentation and Bacterial Community Diversity, Co-Occurrence and Functionality of the Whole-Plant Corn Silage.

ABSTRACTThe objective of this study was to investigate effects of different lactic acid bacteria (LAB) on the fermentation process of whole-plant corn silage stored at different temperatures based on bacterial community successions, interaction networks, and predicted functions. Before ensiling, whole-plant corn was inoculated with L. plantarum (LP) or L. buchneri (LB) and the silage bags were stored at 20 or 30°C, and sampled after 0.5, 1, 3, 7, 14, and 60 d of ensiling. The higher abundances of Leuconostoc, Pedicoccus and Weissella were observed in silage stored at 30°C after 12 h of ensiling, thereby rapidly decreased pH to about 4.5. According to meta-network analysis, the bacterial communities were more sensitive to storage temperature than LAB inoculants during whole-plant corn ensiling. Species of Lactobacillus and Weissella were sensitive to 30°C, while Leuconostoc species were sensitive to 20°C in whole-plant corn silage. The storage temperature of 30°C decreased bacterial diversity and network complexity of whole-plant corn silage compared with 20°C. Additionally, LP inoculation changed the bacterial community successions during the early and middle ensiling periods, while LB inoculation affected bacterial community successions in the later stage of ensiling. The metabolic pathways of bacterial community were totally different in LB-inoculated silage from that in control and LP-inoculated silage. As the bacterial compositions became simple along with the ensiling process, the functional structure of bacterial community became simplified as well. In general, the storage temperature had a greater impact on the fermentation characteristics, bacterial community and predicted function of whole-plant corn silage compared with LAB inoculations.IMPORTANCE Increased understanding of effects of regulation measures on whole-plant corn silage is important from bacterial community succession, interaction network and predicted functions. According to alpha diversity and meta co-occurrence network, the bacterial communities were more sensitive to storage temperature than LAB inoculants during whole-plant corn ensiling. The storage temperature of 30°C decreased bacterial diversity and network complexity of whole-plant corn silage compared with 20°C. In addition, 30°C promoted the initiation of LP and LB inoculants, and 20°C was conducive to the long-term growth of LP and LB inoculants. According to the changes of bacterial community and predicated functions, it was further confirmed that the effect of LB inoculation was more obvious on whole-plant corn silage.

Biotechnology of Newly Created Bacterial Composition for Siloing Based on Lactic Acid Bacteria

Peculiarities of high-quality silage production are the use of biological products based on lactic acid bacteria. The composition of such starters varies greatly according to the use of bacterial cultures, so among the starters available on the market, the range of their effectiveness is also different. It is very common to use a one-sided approach to the choice of bacterial components, which in combination with imperfect production technology have low preservative activity. The study of combined preparations, which combine homo- and heterofermentative types of lactic acid fermentation, allows to stabilize the preservative properties throughout the ensiling time, and increase the aerobic stability of the silage after access of oxygen. Aim. Development of biotechnology of bacterial preparation for corn ensiling, optimization of cultivation conditions of newly created bacterial composition, and selection of cryoprotectants for its lyophilization. Methods. The combined preparation was created on the basis of heterofermentative strain Lactobacillus buchneri 3806 combining it in two- and three-strain compositions with other representatives of lactic acid bacteria, which are characterized by obligate homofermentative and facultative heterofermentative types of metabolism. Optimization of the environment and technological parameters was carried out using a central-compositional plan, further statistical analysis of the obtained data and determination of optimal values of input parameters according to the created mathematical model of optical density response. The effectiveness of the selected protective media was tested for the survival of bacteria after lyophilization. Results. The most effective bacterial composition was found during experiments: L. buchneri 3806, Enterococcus faecium C-8-12, L. plantarum 3216. The effectiveness of the obtained composition was tested by laboratory silage of corn. Tests of the drug based on the selected bacterial composition showed an improvement in the chemical composition of the silage compared to the untreated control and treated only with monoculture L. buchneri 3806, namely: there was a decrease in dry matter loss by 2.21% and 2.04%, 22 due to the increase of lactic acid content, and increase of aerobic stability of silage – 341 h against 57 h of the control sample, and 313 h in case of using monoculture. For the obtained bacterial composition, the culture medium of the following composition was optimized: base (hydrolyzed milk with the addition of the following components: monosubstituted potassium phosphate – 2 g/L; 5-aqueous manganese sulfate – 0.05 g/L; 7-aqueous magnesium sulfate – 0.2 g/L; twin-80 – 1.0 g/L); glucose – 19.7 g/L; yeast extract – 7.8 g/L; corn extract – 23.6 g/L; peptone – 9.1 g/L; sodium citrate – 6.6 g/L; sodium acetate – 3,4 g/L. Cultivation of the bacterial composition on an optimized medium made it possible to obtain the maximum biomass yield, at which the optical density was 2.01 units, which is almost twice as much as the value obtained by culturing the same composition in MRS medium. The optimal technological parameters of culturing the bacterial composition were established, namely the best growth was observed at a temperature of 36.4±0.4°C with constant maintenance of the pH value in the culture medium at the level of 6.5±0.1 units. In addition, the optimal composition of the protective medium containing sodium citrate, sucrose and agar was selected, and ensures the survival rate of lactic acid bacteria 98.4% after lyophilization. Conclusions. The newly formed bacterial composition can be used for the production of preparations for corn silage, and tested on other raw materials, in particular on some perennial legumes (alfalfa, clover), and the conditions of its production can be used to scale the technology.

Probiotic Characteristics of Ligilactobacillus salivarius AS22 Isolated from Sheep Dung and Its Application in Corn-Fox Tail Millet Silage

The forage crops corn (Zea mays) and foxtail millet (Panicum italicum L.) are widely used as animal feed because of their high nutritive values. The ensiling of corn and foxtail millet is often associated with the growth of undesirable microbes, which cause severe loss of dry matter content during the storage periods. The selection of suitable Ligilactobacillus species for corn-fox tail millet silage production can improve the quality. In this study, we aimed to select potent lactic acid bacteria (LAB) from sheep dung and analyses their biological application such as probiotic features, antimicrobial activities and fermentation capability of silage. A total of nine Lactobacillus strains were inoculated in MRS medium to evaluate lactic acid concentration. The isolated strain, Ligilactobacillus salivarius AS22, produced a higher lactic acid level (40.2 ± 2.2 µg/mL) with high growth rates (2.24 ± 0.12 OD at 600 nm) compared to other strains. The silage treated with inoculant (L. salivarius AS22) decreased the pH value (p < 0.05) and enhanced lactic acid production (p < 0.05) than the control at ensiled silages. LAB inoculated silage had reduced numbers of fungal colonies than control (p < 0.05). In conclusion, the addition of L. salivarius AS22 improved the quality of whole corn and foxtail millet silages with significant probiotic potential.

Eligibility criteria for joint ensilage of maize and yellow lupine on poorly productive lands of the Upper Volga region

In the modern conditions of RF agro-industrial complex development, the transfer of animal husbandry to an industrial basis is possible only with high-grade vegetable protein production increase. Silage of the aboveground mass of pure corn during all phases of plant growth and development does not provide the content of nutrients in the feed unit according to the zootechnical requirements. Therefore, to optimize the finished feed in terms of the carbohydrate-protein ratio, green mass of legumes should be added to its composition during the preparation of silage from corn. The selection of the legume component should be carried out taking into account the following main criteria: coincidence with corn by the growing season duration, the same attitude to soil and climatic resources and insolation conditions, high provision of the legume component with digestible protein, dry matter, starch and exchange energy during the ensiling period. It has been established that the joint ensiling of corn with yellow lupine is expedient when the corn is in waxy ripeness, and the lupine is in the phase of shiny beans with the component ratio of 55:45%. In this case, the content of digestible protein in 1 feed unit of finished silage is 100.2 g at reliable feed supply with both irreplaceable (36.0 g) and critical (7.2 g) amino acids.

The bacterial community and metabolome dynamics and their interactions modulate fermentation process of whole crop corn silage prepared with or without inoculants.

SummaryMulti‐omics approach was adopted to investigate the modulation of bacterial microbiota and metabolome as well as their interactions in whole crop corn ensiling systems by inoculating homofermentative Lactobacillus plantarum or heterofermentative Lactobacillus buchneri. Inoculations of the two different inoculants resulted in substantial differences in microbial community and metabolic composition as well as their dynamics in ensiled corn. Inoculants also altered the correlations of microbiota in different manners, and various keystone species were identified in corn silages with different treatments. Many metabolites with biofunctional activities like bacteriostatic, antioxidant, central nervous system inhibitory and anti‐inflammatory were found in the present silage. A constitutive difference in microbiota dynamics was found for several pathways, which were upregulated by specific taxa in middle stage of fermentation, and widespread associations between metabolites with biofunctions and the species of lactic acid bacteria dominated in silage were observed. Multiple microbial and metabolic structures and dynamics were correlated and affected the fermentation process of the corn ensiling systems. Results of the current study improve our understanding of the complicated biological process underlying silage fermentation and provide a framework to re‐evaluate silages with biofunctions, which may contribute to target‐based regulation methods to produce functional silage for animal production.

Microbial Community and FermentationDynamics of Corn Silage Prepared withHeat-Resistant Lactic Acid Bacteria in a HotEnvironment.

To develop a silage fermentation technique to adapt to global climate changes, the microbiome and fermentation dynamics of corn silage inoculated with heat-resistant lactic acid bacteria (LAB) under high-temperature conditions were studied. Corn was ensiled in laboratory silo, with and without two selected strains, Lactobacillus salivarius LS358 and L. rhamnosus LR753, two type strains L. salivarius ATCC 11741T and L. rhamnosus ATCC 7469T. The ensiling temperatures were designed at 30 °C and 45 °C, and the sampling took place after 0, 3, 7, 14, and 60 days of fermentation. The higher pH and dry matter losses were observed in the silages stored at 45 °C compared to those stored at 30 °C. Silages inoculated with strains LS358 and LR753 at 30 °C had a lower ratio of lactic acid/acetic acid. The dominant bacterial genera gradually changed from Pediococcus and Lactobacillus to Lactobacillus in silages during ensiling at 30 °C, while the bacterial community became more complex and fragmented after 7 d of ensiling at 45 °C. The high temperatures significantly led to a transformation of the LAB population from homo-fermentation to hetero-fermentation. This study is the first to describe microbial population dynamics response to high temperature during corn ensiling, and the results indicate that L. rhamnosus 753 shows potential ability to improve silage fermentation in tropics and subtropics.

Qualitative monitoring of corn silage stored in commercial bunker silos and used as feed for dairy cattle in the western region of Santa Catarina State, Brazil

Corn ensiling is a feed preservation practice used for ruminant production. During the process of making and opening the silos, the quality of the silage may change due to the entrance of air, which can cause damage and decrease the voluntary intake of the animals. The objective of this work was to evaluate the chemical composition of corn silages during their use in commercial bunker silos, as well as to correlate this with qualitative and quantitative characteristics related to the silage making process. Technical data on silage making and samples were collected from 14 bunker silos, with five samples collected along each silo (at 10, 30, 50, 70 and 90% of their lengths); additionally, two sampling methodologies were compared (“W” vs. layer collections in silo panels: top, middle and bottom). The values for the pH and titratable acidity (TA) were significant (p < 0.05) in relation to the sampling method, where the pH of the top was higher (3.8±0.5) than that of the middle and the bottom layers (3.6±0.3 and 3.5±0.3); therefore, the TA was lower in the top of the silos. The dry matter, ashes, crude protein, neutral detergent fiber, acid detergent fiber, pH, TA, as well as the silo sampling method during the unloading of commercial bunker silos did not differ for any of the variables (p < 0.05). Also, the particle size did not differ during the unloading of the commercial bunker silos (p > 0.05). According to the collected technical data, 78.57% of the bunker silos were built directly on the ground, the harvesting equipment was mostly borrowed from municipalities or farmers’ associations (for 35.7 and 28.5% of the farms, respectively), and in only 64.2% of the farms, the harvester was sharpened before silage cutting. Good practices were applied during the corn silage process and throughout the use of the silos, homogeneous quality was detected in the western region of Santa Catarina. Either “W” or layer collections can be used to sample corn silage.

Microbiome dynamics during ensiling of corn with and without Lactobacillus plantarum inoculant.

Microbial population dynamics associated with corn silage, with and without Lactobacillus plantarum treatment, was studied. Whole crop corn was ensiled using laboratory silos and sampled at different times, up to 3months. The dominant bacteria, before ensiling, were Acinetobacter (38.5%) and Klebsiella (16.3%), while the dominant fungi were Meyerozyma (53.5%) and Candida (27.7%). During ensiling, the microbial population shifted considerably, and Lactobacillus (> 94%) and Candida (> 74%) became the most dominant microbial genera in both treated and untreated silages. Yet, lactic acid content was higher in the treated silage, while the microbial diversity was lower than in the untreated silage. Upon aerobic exposure, spoilage occurred more rapidly in the treated silage, possibly due to the higher abundance of lactic acid-assimilating fungi, such as Candida. Our study is the first to describe microbial population dynamics during whole-crop corn ensiling and the results indicate that microbial diversity may be an indicator of aerobic stability.

Giant cane (Arundo donax L.) for biogas production: The effect of two ensilage methods on biomass characteristics and biogas potential

Arundo donax L. is a perennial plant that can substitute for traditional energy crops to produce biogas, reducing costs because of its high biogas yield per Ha cultivated and low agronomic and energetic inputs. Nevertheless, Arundo donax biomass needs to be ensiled to be preserved and used. Because no full-scale data exist about A. donax ensilage and the effect of this process on potential biogas production, in this work two different ensiling techniques, i.e. trench and silo-bag ensiling, were performed at full scale, and the processes studied for 200 days. Results obtained indicated that A. donax could be successful ensiled by using the two approaches. Ensilage proceeded by fermentation of organic acids already present in the biomass, i.e. malic and oxalic acids that were degraded, giving volatile fatty acid accumulation. This was different from corn ensiling characterized by starch fermentation to lactic acids. Biological processes determined a loss of the potential biomethane production, namely −20.1% and −7.6% for trench and silo-bag, respectively. Taking into consideration biomethane yield per Ha and ensilage losses, potential biomethane losses of 5000 Nm3 CH4 Ha−1 for trench silage and of 2000 Nm3 CH4 Ha−1 for silo bag, were estimated, respectively. Nevertheless, taking into consideration the higher biomass and biomethane yields Ha−1 in comparison with the other energy crops, A. donax still remained more efficient and cheaper than traditional energy crops in producing biogas.

Detecting Nitrous Oxide in Complex Mixtures Using FTIR Spectroscopy: Silage Gas

Nitrous oxide (N2O) is a greenhouse gas with about 300 times the global warming potential (GWP) of carbon dioxide (CO2). It is emitted from a wide range of sources and is responsible for about 6% of anthropogenic US greenhouse gas emissions. Analytical techniques are needed that can measure concentrations of N2O rapidly and inexpensively in sources that are also emitting other compounds that may interfere with the analytical process. In this work, we demonstrate the use of Fourier Transform Infrared (FTIR) spectroscopy to analyze N2O in the complex mixture of gases produced during the early phase of the silage making process. Silage gas samples were collected into Tedlar bags from the bucket silos during the first week of corn ensiling. A bag of the silage gas was analyzed using a Bruker FTIR spectrometer coupled with a long optical path length White Cell. First, N2O infrared absorption bands were identified in the FTIR spectra of the silage gas by comparing them to both standard N2O gas and simulated infrared spectra which confirmed that N2O was present in the silage gas. Then, N2O concentration in the silage gas was derived from the FTIR spectra using LINEFIT program. It was demonstrated that FTIR spectroscopy is a viable method for measuring N2O concentrations in the silage gas.

Características agronômicas, bromatológicas e econômicas de alturas de corte para ensilagem da cultura do milho

The aim was to evaluate agronomic, bromatologic and economical characteristics harvest heights for ensiling of corn. The trial was conducted in randomized block design and treatments corresponded to harvest heights of 20; 50; 80 and 110 cm from the soil surface. The agronomic evaluations were conducted 114 days after planting. The percentage of dry matter (DM) and productivity of stem, grain and participation of potassium remaining in the stem increased linearly with increasing cutting height (p<0.05). Therefore, the mass used at ensiling decreased proportionally with increasing cutting height (p<0.05). The silage quality was improved because of the increase in the cutting height. We observed higher crude protein (CP) content and energetic value in the silage harvested at 110 cm from the soil surface, while there was lower fiber content. However, silages produced with plants harvested at 110 cm from the soil surface showed the highest production cost (4.47 times greater than cycling through K in the remainder of the stem). The agronomic and bromatologic characteristics of corn silage improves with increasing cutting height, but the increase cutting height unfeasible economically the practice silage when the generation of final products is not computed. Thus, it is recommended that the cutting height of the corn plant is at most 50 cm.

Effects of ensiling processes and antioxidants on fatty acid concentrations and compositions in corn silages.

BackgroundCorn silage is the main dietary component used for ruminant breeding in China and is an important dietary source of fatty acids for these animals. However, little is known regarding effective means to protect the fatty acid (FA) contents in silages. In this study, we examined the changes in FA contents and compositions during corn ensiling and screened several antioxidants for their inhibition of lipid oxidation during corn ensiling.MethodsWe conducted two different experiments. In Experiment 1, corn was ensiled in 30 polyethylene bottles (bottle volume: 1 L, silage density: 600 g/dm3) and three bottles were opened at 0.5 d, 1 d, 1.5 d, 2 d, 2.5 d, 3 d, 5 d, 7 d, 14 d, and 28 d after ensiling. In Experiment 2, corn was treated with various antioxidants: (1) No additives (CK); (2) BHA (Butylated hydroxyanisole); (3) TBHQ (Tertiary butyl hydroquinone); (4) TPP (Tea polyphenols); and (5) VE (Vitamin E). These treatments were applied at 50 mg/kg and 100 mg/kg of fresh weight with each treatment replicated 3 times.ResultsDuring ensiling in Experiment 1, saturated fatty acids (SFA; C16:0 and C18:0) and malondialdehyde (MDA) contents tended to increase, whereas unsaturated fatty acids (UFA; C18:1, C18:2 and C18:3) tended to decrease. However, these changes were only significant on the first 2 days of ensiling. In Experiment 2, all of the antioxidants tested affected the total FA contents and those of unsaturated fatty acids (C18:1, C18:2 and C18:3) and MDA. The effects of TBHQ and TPP were greater than those of the other antioxidants.ConclusionsThe reduced total FA contents in corn silages were due to unsaturated fatty acids’ oxidation during the early stages of ensiling. Adding an antioxidant could prevent fatty acids’ oxidation in corn silages.

Changes in the concentrations of fumonisin, deoxynivalenol and zearalenone in corn silage during ensilage

We assessed the production of the mycotoxins fumonisin, deoxynivalenol and zearalenone during the ensiling of corn. Corn was harvested at yellow-ripe or full-ripe stage and separated into the stem and leaf parts and the ear parts, including bracts. Each material was ensiled under five conditions: (1) no fungus added, anaerobic conditions; (2) no fungus added, aerobic conditions; (3) mycotoxin-producing fungus added, anaerobic conditions; (4) mycotoxin-producing fungus added, aerobic conditions; and (5) mycotoxin-producing fungus added to autoclaved material, aerobic conditions. After 40 days of ensilage, we analyzed the silage fermentative quality and mycotoxin concentration. The fermentative quality of all materials was good in treatments (1) and (3), because the pH < 4 increased the lactic acid content preventing mycotoxin levels from increasing. In treatments (2) and (4), fermentative quality of all materials was poor, and mycotoxin levels were slightly increased. In treatment (5), fermentative quality was poor, and mycotoxin levels were increased remarkably. These results indicate that mycotoxins are not produced under anaerobic conditions and are hardly produced under aerobic condition during the ensiling of corn. Our findings suggest that almost all mycotoxins in corn silage are produced pre-harvest.

Effect of inoculated corn silage on rumen fermentation and lipid metabolism in an artificial rumen (RUSITEC)

Effects of providing substrates containing corn silage (12 g of DM/day) and lucerne hay (3 g DM/day) to an artificial rumen (RUSITEC) in which the whole plant corn was not inoculated (CS, control), or inoculated with Lactobacillus plantarum CCM 4000 (CS + LP), Lactobacillus fermentum LF2 (CS + LF) or Enterococcus faecium CCM 4231 (CS + EF) on rumen metabolism was examined. The inoculants were promising probiotic- and bacteriocin-producing strains. The substrates were fermented in fermentation vessels for 11 days, which included a stabilization period of 5 days. The counts of inoculants decreased during ensiling of corn, and at the end of ensiling (105 days), their counts were less than 1.0 log 10 cfu/g; probably for lower pH (3.44–3.54). Organic matter and neutral detergent fibre degradabilities were increased in inoculated CS compared to control. Ammonia N production was decreased in all inoculated substrates. From other fermentation parameters, only total VFA production, production of acetate, n-butyrate (mmol/day) significantly increased during fermentation of CS + LP and CS + LF substrates compared to control. The inoculated CS substrates influenced the efficiency of microbial protein synthesis ( P<0.001). Biohydrogenation of C 18:1, C18:2 and total C18 FA increased in all inoculated CS substrates in fermentation fluid in RUSITEC. The concentration of trans 11 C18:1 (TVA) was unchanged in inoculated CS substrates and the concentration of cis 9, trans 11 C18:2 (CLA) were decreased ( P<0.05) compared in CS. All inoculants of whole plant corn were not effective for increasing CLA and TVA concentration in fermentation fluid and for decreasing of rumen biohydrogenation of C18 fatty acids in RUSITEC.

A Comprehensive Model of Forage Changes in the Silo

ABSTRACT Amodel describing the ensiling of corn and alfalfa in top- and bottom-unloaded tower and bunker silos was developed and evaluated. Oxygen infiltration through the silo wall or cover caused most of the dry matter loss with the rate of loss primarily influenced by silo size, wall or cover permeability and the length of the storage period. A change in wall permeability from 2 to 4 cm/h increased loss 2.0% in a medium-sized, top-unloaded tower silo. Emptying this silo in 120 days rather than 360 days reduced loss 6%. Dry matter loss was relatively insensitive to initial crop quality and moisture content over the range of 50-65% moisture. Ensiling losses were similar between corn and alfalfa.