Small Scale Silos Research Articles

Fermentation characteristics of maize–forage legume mixtures ensiled in small-scale silos

This study was conducted to evaluate the ensiling characteristics of maize–forage legume mixtures in small-scale silos. Sole and intercrops forage materials were harvested 80 days after planting and ensiled in small-scale silos, that is: plastic bags, plastic drums, and small pits, for 60 days. After ensiling, samples were collected to examine the chemical composition, microbial community and fermentation quality. Mixed silages stored in the drum silos had significantly (p ≤ 0.05) higher DM content (35.69%) than that from pit and bag silos. The drum silos had significantly (p ≤ 0.05) higher crude protein concentration (20.57% DM) in sole legume silages than other silo types. Neutral detergent fibre concentration (39.76% DM) of sole forage silages was greatest in bag silos than in other silos. High in vitro dry matter digestibility and water-soluble carbohydrate values (58.15 and 12.19% DM respectively) for mixed silages were recorded in drum silos. Bag silos showed lower numbers of lactic acid bacteria and higher populations of enterobacteria (4.86 and 4.26 log10 CFU g−1 respectively) in sole forage silages than other silos. Mixed silages ensiled in drum silos produced significantly lower (p ≤ 0.05) pH (3.03) and ammonia nitrogen content (3.73% TN) compared to pit and bag silos. The study concluded that ensiling maize–forage legume mixtures in drum silos can have a positive effect on the nutritive value of ruminants’ feeds. Therefore, the recommended forage type for ensiling is mixed silages.

Investigation of the effect of different additives on the qualities, <i>in vitro</i> degradation, and rumen fermentation profile of indigo waste silage

<abstract> <p>Natural indigo dye production produces indigo waste as a by-product. Our purpose of this study was to examine the effects of calcium hydroxide (Ca(OH)<sub>2</sub>), cellulase (CE), molasses (MO), and their combinations on the silage quality, <italic>in vitro</italic> degradability, and rumen fermentation parameters of indigo waste silage. A completely randomized design (CRD) was used for the experiment. Indigo waste was chopped and ensiled in a small-scale silo with no additive (control), Ca(OH)<sub>2</sub>, MO, CE, Ca(OH)<sub>2</sub>:MO, Ca(OH)<sub>2</sub>:CE, MO:CE, and MO:CE:Ca(OH)<sub>2</sub>. After 30 days of storage, the silages were tested for quality and chemical composition, as well as an <italic>in vitro</italic> fermentation. The ruminal fluid inoculum was collected from two beef cattle with a body weight (BW) of 200±10 kg, and the inoculum had been pre-heated before being transported to the laboratory. Silage with MO, CE, or their combination increased the amount of lactic acid (<italic>p</italic> < 0.01). The silage pH was lowest in MO:CE (4.5) and was highest in Ca(OH)<sub>2</sub>:CE (10.6) in indigo waste (<italic>p</italic> < 0.01). In comparison to the control (19.5% CP), the CP content of all additives increased by 20.7% to 21.5% (<italic>p</italic> = 0.02). The addition of Ca(OH)<sub>2</sub>:MO and Ca(OH)<sub>2</sub>:CE resulted in a reduction of NDF content by 60.7% and 59.4%, respectively, in comparison to the control group (72.4%) (<italic>p</italic> < 0.01). Silage with additives had no effect on the cumulative gas production or gas kinetics, except that the constant rate of gas production for the insoluble fraction (c) was higher in MO (<italic>p</italic> = 0.03). <italic>In vitro</italic> dry matter degradability (IVDMD) was higher in CE and MO and highest in MO:CE-treated silage (<italic>p</italic> < 0.01). The <italic>in vitro</italic> organic matter degradability (IVOMD) increased in Ca(OH)<sub>2</sub>:MO compared with the control (<italic>p</italic> = 0.03). The additives alone or in their two combinations in silage reduced the ruminal ammonia-nitrogen (NH<sub>3</sub>-N) concentration (28.0 to 31.5 mg/dL) when compared to the control (32.7 mg/dL) (<italic>p</italic> < 0.01). In addition, the highest total volatile fatty acid (VFA) level was found in the silage of the MO (92.9 mmol/L) compared with the control (71.3 mmol/l) (<italic>p</italic> < 0.01). The proportion of propionic acid and butyric acid increased (<italic>p</italic> < 0.01) whereas acetic acid decreased (<italic>p</italic> < 0.01) in the rumen of silage with MO and CE. In summary, the addition of MO and CE has the potential to be used in the silage of indigo waste.</p> </abstract>

In Vitro Rumen Fermentation of Coconut, Sugar Palm, and Durian Peel Silages, Prepared with Selected Additives

Understanding the nutritive values of fruit peel residues could expand our feed atlas in sustaining livestock production systems. This study aimed to investigate the effects of lactic acid bacteria (LAB), cellulase enzyme, molasses, and their combinations on the fermentation quality and in vitro digestibility of coconut peel (CCP), sugar palm peel (SPP), and durian peel (DRP) silage. The CCP, SPP, and DRP were ensiled in a small-scale silo without additive (control), and with LAB strain TH14 (TH14), molasses, or Acremonium cellulase (AC) using a small-scale silage preparation technique according to a completely randomized design. All fresh peels had sufficient factors for ensiling such as moisture content (78–83%), water-soluble carbohydrates (WSC, 4.20–4.61% dry matter (DM)), and epiphytic LAB population (104–105 colony-forming units (cfu)/g fresh matter (FM)). However, aerobic bacteria counts were high (107–109 cfu/g FM). The fiber content of these fruit peels was high, with lignin abundances ranging from 9.1–21.8% DM and crude protein was low (2.7–5.4% DM). After ensiling, the pH values of the silage were optimal (≤4.25) and lower (p < 0.01) for SPP silage. The addition of molasses+TH14, molasses+AC, and molasses+TH14+AC has the potential to enhance fermentation characteristics and improve chemical composition. Silages treated with molasses alone improved the in vitro digestibility of tropical fruit peels. The residue of tropical fruits has the potential to be used as an alternative feed source for ruminants. Adding molasses, TH14, and AC during silage preparation could improve its nutritive value and digestibility.

Filling of a grain silo. Part 1: Investigation of fine material distribution in a small scale centre-filled silo

When a silo is being filled with the granular material containing a range of particle sizes, larger particles tend to flow towards the silo wall while the smaller particles accumulate near the centre of the silo. Shelled corn was used in this study. This work encompasses the first part, where the distribution of broken corn and foreign material (BCFM) was investigated in a small scale silo filled from a central filling point (CFP). Factors that were varied included initial BCFM, volume flow rate of material and fill pipe diameter. A new approach was developed to ensure accurate sampling in the radial and vertical direction in the silo. The results indicated that the distribution of fine material became more uniform at lower grain depths and for increasing initial BCFM, volume flow rate and fill pipe diameter. The accumulation of fine material at the centre of the silo increased with increase in the distance from the bottom of the silo. In addition, a nonlinear model was developed to predict BCFM distribution in CFP method. Based on statistical parameters, namely, coefficient of determination (R2), Chi-square (χ2), RMSE (root mean square error) and MRDM (mean relative deviation modulus), the model fit the experimental data reasonably well.

Filling of a grain silo. Part 2: A new filling method for uniform distribution of fines in a small scale silo

During top filling of a storage silo, granular material containing a range of particle sizes, the smaller particles (fine material) accumulate under the filling point. This interferes with air distribution preventing effective aeration of regions with higher percentages of fine material. In the first part of the study, the distribution of broken corn and foreign material (BCFM) was investigated in a small scale silo filled from a central filling point (CFP). In this second part, a new variable filling point (VFP) method was developed and tested as a means of reducing the non-uniform distribution of fine material during filling. The VFP mechanism produces rotational and diametric motion of the fill pipe using a rotating rim placed at the top of the experimental silo. Factors that were varied included initial BCFM (BCI), volume flow rate of material (Q), fill pipe diameter (DF) and ratio of rotational velocity of the rim to the linear velocity of the fill pipe (VR/VL). The findings of the VFP experiments demonstrated that the distribution of fine material became more uniform with increasing VR/VL, BCI, Q, and with decreasing DF. The comparison between CFP and VFP experiments showed that the proposed VFP filling method gave a more uniform distribution of fine material, eliminating zones with high concentrations of fines.

Storage of WDGS under hermetic and non-hermetic conditions: Effect on sensory properties, microorganisms, mycotoxins and nutritional value

WDGS production in Argentina substantially increased in the last 5 years and become a frequent constituent for feed diets. However, due to the extremely high moisture content of the product, quality deterioration occurs in a few days under aerobic conditions; which creates a series of logistical problems for expanding the use of WDGS far away from production plants. Silo bag technology, a flexible hermetic storage system extensively used in Argentina, could be a good alternative for extending the storage time of WDGS. Thus, the main goal of this research was to compare the effect of hermetic and non-hermetic storage of WDGS using several quality parameters. Samples of WDGS from three different ethanol production plants were stored in hermetic (small scale silo bags) and non-hermetic conditions at 16 °C (60 days hermetic and 20 days no-hermetic). WDGS quality evolution was evaluated through sensory, microbiological, biochemical, nutritional and toxicological parameters. Results indicated that in the non-hermetic treatment, even though no evidence of nutritional quality losses was found in the mass of WDGS, spoilage developed at the surface after 10 day of storage. Additionally, evidence of mycotoxin formation was found (DON) during aerobic storage, implying that mycotoxin tests should be routinely implemented. On the contrary, hermetic storage in silo bag allowed a proper ensiling process, extending the shelf life of the product and preventing mycotoxins development for at least 60 days.

Effects of Three Different Additives and Two Different Bulk Densities on Maize Silage Characteristics, Temperature Profiles, CO2 and O2–Dynamics in Small Scale Silos during Aerobic Exposure

Silage quality and aerobic stability are sometimes insufficient. If management requirements are not met, or to improve silage quality, additives are often used. The objective of this study is to investigate the effects of different factors on silage during aerobic conditions. Whole-crop forage maize was harvested and 24 buckets (65 L) were filled and assigned to one of four treatment groups: (1) control (no treatment); (2) chemical additive (sodium benzoate, potassium sorbate, sodium acetate); (3) a mixed biological inoculant containing Lactobacillus buchneri, L. plantarum, and Pediococcus acidilacti; and (4) a mixed biological inoculant containing L. buchneri, L. plantarum, and L. rhamnosus. An untreated variation was also ensiled. Two different densities were adjusted during ensiling. After opening, the temperature was measured for seven days and O2 and CO2 concentrations were analysed. The findings show that the chemical additive very effectively prevented silage from reheating and deteriorating. Aerobic reheating of silage was also successfully inhibited through biological additives and high density.

USE OF SPATIOTEMPORAL DIAGRAMS TO CHARACTERIZE A SILO DISCHARGING PROCESS

To get a better knowledge of discharging flows of ensiled granular materials, a small scale silo was designed and built. It is equipped with a flat bottom and it has a rectangular cross section. Moreover, it is entirely transparent for image processing purpose. First of all, a physical and mechanical characterization of wood granules (inert materials) was performed using a shear box testing. Then, silo emptying flows were generated. Flow regimes and flow rate were determined using spatiotemporal diagrams extracted from images of the free surface of the ensiled material. The same method was then used to measure the flow rate of discharging flows of soya, colza and rye seeds which were characterized in a previous study. For each material studied, the flow rate measured with this non intrusive method was successfully compared with a direct method consisting in weighing a volume of grains discharged during a unit time and with Berveloo’s formula.

Effect of stage of growth on the chemical composition, nutritive value and ensilability of whole-crop barley

Chemical composition, nutritive value and ensilability of whole-crop barley as a supplementary feed for dairy cows was investigated using a range of maturities of barley (seed coat ripe—GS 69, early dough stage—GS 82, soft dough—GS 87 and grain ripe—GS 90) in small scale silos. The ensiling experiment was based on a complete randomised design with three replicate silos per harvest date. Twelve 0.225 m 3 plastic silo (were used in the experiment and silo were sampled on opening for chemical composition and nutritive value. The fermentation process reduced the concentrations of water-soluble carbohydrate in the ensiled forage compared to the fresh forage. The proportion of residual WSC in silage did however increase with increasing crop maturity (0.051, 0.077, 0.167 and 0.560 of WSC retained in the silage after the process of fermentation from forages cut at GS 69, 82, 87 and 90 respectively). Silages that were made from forage cut at the most mature stage of growth had a substantially lower production (P<0.001) of total fermentation acids (38.9 g/kg DM for GS 90) compared to those made from the least mature forage (203.4 g/kg DM for GS 69). The pH and concentrations of the various fermentation acids for silages made with the least mature forage (GS 69) were typical of acetic acid dominated fermentation. These silages contained little or no butyric acid and had a pH of 4.5 and contained high concentrations of ammonia-N (186 g/kg total N). Silages produced from forages cut at growth stage 82 were similar to those conserved from immature forages, having acetic acid dominated fermentation (lactic acid to acetic acid ratio of 1:1.22), relatively high pH (4.85) and high concentrations of ammonia-N (141 g/kg total N). These silages differed from those made from the most immature forage insofar that they contained high concentrations of butyric acid (50.5 g/kg DM). The processes of fermentation were affected by the stage of growth of the forage at ensiling and hence the economics of silage production. If the forage was too immature at ensiling, the yield of crop would be compromised but the silage produced may have moderate to high nutritive value and reasonable aerobic stability during the feed out phase. If the whole-crop forage was grown as a crop to secure high levels of supplementary feed from an alternative forage source (other than grass), the trade-off between yield, nutritive value and losses of feed immediately after silo opening would suggest the crop should be harvested between 350 and 450 g DM/kg dry matter.

Effects of slurry application method and timing on grass silage quality

Small-scale silos (60-litre polyethylene barrels) were used to examine the chemical composition of grass silage after the application of slurry, at 40 m3/ha, at a range of timings, at two sites with contrasting rainfall; North Wyke, in Devon (high rainfall) and Reaseheath College, Cheshire (low rainfall). Grass plots (60 m2) received cattle slurry via surface broadcast (S), shallow injection (I) or surface placement by trailing shoe (T) techniques at 10, 6 or 2 weeks before an early silage (first) cut in May/June, and 6 or 2 weeks before a second cut in June/July. Control plots (C) received no slurry treatment. The harvested grass was compressed and sealed in the experimental silos and samples of the herbage at ensiling and of ensilage (after &gt;100-day fermentation) were analysed for various chemical components. Herbage yield was measured when the harvests were taken. Wetter than average weather conditions in both years resulted in silages with variable DM content (range 140–277 g/kg) being made at both sites. Generally, silages were poorly preserved with high pH and NH4+-N and low lactic acid contents. In particular, the silages from treatment S where slurry was applied 2 weeks prior to harvest exhibited characteristics indicative of clostridial growth, with high pH (range 4·0–5·2) and NH4+-N (106–213 g/kg total N) and low lactic acid (16–86 g/kg DM) contents. Damage to herbage caused by the injection tines on taller swards (treatments I at 6 and 2 weeks before cutting) was evident and the injection process was impeded by tall grass. This contributed to herbage contamination with soil and slurry on these treatments and, consequently, to poor silage fermentation. Silages made with slurry application method T at all timings showed improved fermentation characteristics compared with the other treatments, particularly at North Wyke. The results indicate that silage quality is unlikely to be compromised by slurry applications made in early spring, during February, March or even in April, where these are at agronomically sensible rates. Such practice will enable better utilization of slurry nitrogen (N), reducing risks of nutrient losses via leaching or surface runoff. Furthermore, shallow injection and, particularly, trailing shoe slurry application techniques may be used to increase flexibility of slurry management by allowing more immediate spreading before cutting than with conventional surface broadcasting, without detriment to silage quality.

Changes in chemical composition and nutritive value of urea treated whole crop wheat during exposure to air

Utilisation of winter wheat for silage production is popular in northern Europe as the crop can be grown in a wide range of climates and soil conditions. However, unacceptable losses of dry matter (DM) and a decline in nutritive value of the ensiled crop can occur during conservation and feed-out. Changes in chemical composition and nutritive value of fermented whole crop wheat during exposure to air was investigated using a range of maturities of wheat (growth stages (GS) 49 (boot), 71 (seed coat water ripe) and 87 (hard dough)) and levels of urea (0, 20 and 40 kg/t DM) in small scale silos. The experiment was a factorial design with initial DM of forage, level of application of urea and period of exposure of silage to air being the factors. The effect of increasing concentration of urea reduced the maximum temperature of the silage on exposure to air ( P<0.001) and increased the time taken to achieve the maximum temperature ( P<0.001). Increasing the initial DM content of forage ensiled depressed the maximum temperature recorded in the silo as well as increased the period of time to reach maximum temperature ( P<0.001 for both effects). Losses in DM from the conserved forages were greatest in crops ensiled at an immature stage of growth not treated with urea. Addition of urea at ensiling reduced the losses in DM ( P<0.001). However, at intermediate stages of growth (GS 71) and low levels of application of urea (20 kg/t DM), the rate of loss of soluble carbohydrates were increased ( P<0.05) compared to untreated forages. Ammonia released as a result of urea treatment at ensiling reduced the rate of loss of DM and of loss of nutritive value (neutral detergent cellulase digestion (NDCD); P<0.001). However, no changes in the concentration of starch during exposure to air were observed for any treatment. Treatment of whole crop wheat with urea is an effective method of preserving forage nutritive value during ensiling and on exposure to air at feed-out.

Effect of stage of growth at harvest and level of urea application on chemical changes during storage of whole-crop wheat

Winter wheat ( Triticum aestivum L.) harvested at a range of stages of growth has become a popular conserved forage for winter feeding of dairy cattle. The detailed processes of the preservation of whole-crop wheat were studied in three experiments in 1989 (Experiment 1) and in 1990 (Experiments 2 and 3). A range of maturities of wheat (growth stages 49, 71 and 87 in Experiment 1 and growth stages 53, 70, 80, 83 and 85 in Experiment 2) were selected and ensiled with three (0, 20 and 40 kg (t DM) −1; Experiment 1) or four rates (0, 20, 40 and 60 kg (t DM) −1; Experiment 2) of application of urea in small-scale silos. The experiments were based on factorial designs with crop maturity (oven dry matter (DM) content) and level of application of urea as the principal factors. Experiment 3 considered the changes in chemical composition over time (silos opened after 0, 10, 20, 30, 60 and 90 days ensiling) at two level of urea treatment (0 and 40 kg (t DM) −1) and two stages of growth (GS 70 and 83). The rate of hydrolysis of urea was dependent on the moisture content of the ensiled forage and the level of urea applied (Experiment 3). Microbial activity, measured by the production of total fermentation acids (lactic acid+VFA), was progressively reduced in both experiments by the level of urea applied ( p<0.001; Experiments 1 and 2) and increasing maturity of forage at harvest ( p<0.001; Experiments 1 and 2). An interaction ( p<0.001; Experiments 1 and 2) was observed for production of total fermentation acids between level of urea applied and maturity of forage, reflecting the relative availability of nutrients, in particular sugars (WSC)) for microbial utilization. Losses of DM during ensiling were progressively reduced ( p<0.001; Experiments 1, 2 and 3) by the addition of urea at ensiling and by increasing maturity of the forage ( p<0.001; Experiments 1 and 2) and duration of storage (Experiment 3). Ensiling the forage without urea reduced its NDF content ( p<0.01; Experiment 1 and p<0.001, Experiment 2), but with increasing crop maturity the extent of the reduction in NDF was decreased. Application of urea at a rate >40 kg (t DM) −1 increased ( p<0.01; Experiments 1 and 2) the reduction in NDF content compared to forage ensiled without urea. Treatment of harvested forage at ensiling with urea reduced ( p<0.001; Experiments 1 and 2) the conversion of WSC to fermentation acids during conservation but slightly enhanced the loss of starch ( p<0.05; Experiment 2). There was a marked reduction (ranging from 6 to 17 g kg −1 ( p<0.01); Experiments 1 and 2 to 23 g kg −1 ( p<0.01); Experiment 2) in the digestibility of the ensiled forage compared to fresh forage, dependent on maturity of the forage, but no differences in digestibility were observed between urea treated forage and fresh forage. Treatment of whole-crop wheat forage with urea at harvest can be considered an effective method of preserving forage nutritive value.

Ensiling of whole-crop wheat with cellulase-hemicellulase based enzymes. 1. Effect of crop growth stage and enzyme on silage composition and stability

Whole-crop wheat was harvested at the heading, mealy-ripe, medium-dough and hard-dough stages of grain development corresponding to crop dry matter (DM) contents of 310 g DM kg −1, 405 g DM kg −1, 520 g DM kg −1 and 680 g DM kg −1, respectively. Crop from each harvest was either untreated or treated with one of two enzyme additives (Clampzyme or Deezyme) at three application rates of 333, 667 and 1000 ml t −1 DM and 1000, 1334 and 1667 ml t −1 DM (low, medium and high level) for Clampzyme and Deezyme, respectively. Crop from each harvest was ensiled in 5.0 kg quantities in polythene-bag silos, and sealed either immediately or after 24 h. Contents of DM, acid detergent fibre, neutral detergent fibre and in vitro digestible organic matter increased with advancing maturity, but contents of nitrogen, water-soluble carbohydrates and fermentation products decreased. Silage stability, as measured by silo DM loss when exposed, also increased as crops matured. Compared with untreated crop, enzyme treatment increased lactic and acetic acid contents and decreased pH, but these effects were more pronounced in less mature crops. Neither fibre content nor in vitro digestible organic matter content were affected by enzyme treatment; increasing levels of enzyme did not affect silage composition. An interesting finding was that delaying silo sealing by 24 h improved fermentation and improved the aerobic stability of silages. Albeit using small-scale silos, it is concluded that whole-crop wheat may be harvested at DM contents of up to 700 g DM kg −1 (hard-dough stage) and be effectively preserved by ensiling. Addition of cellulase-hemicellulase-based enzymes would enhance fermentation when ensiling less mature (less than 500 g DM kg −1 wheat.

Evaluation of conditions for fermentation of fish offal

Conditions for the lactic acid fermentation of fish offal were evaluated regarding the effect of substrate concentration (2, 5 and 10% dextrose), preacidification with lactic acid (initial pH of 6.8, to 6.5 or 6.0), and inoculum size of Lactobacillus plantarum (107 , 108 and 109 colony forming units (cfu)/g). pH and lactic acid production were monitored during a two-week storage period. A small-scale silo for fermenting fish offal was also constructed, and measurement of redox potential was evaluated as a means to estimate bacterial growth conditions. The most favourable conditions for fermentation, manifested by a low and stable pH and high lactic acid production, were achieved with an inoculum size of 108 cfu/g and 5% dextrose. Preacidification did not affect final pH. Redox potential was shown to give a reliable estimate of growth conditions for bacteria under anaerobic conditions by rapidly falling to below -550mV in silage with a high lactic acid concentration.

鋼製サイロの振動特性に関する研究 : 各種粉粒体の有効質量と実大振動実験について

This paper is a report on the equivalent mass of many kinds of grain and powder. We observe the experiment of the real-scale silo, and compare with the results obtained with the small-scale silo. From the results of this experiment, we can observe the vibration characteristics for the first and second normal modes and make a new model for analysis of the vibration of silos. Appling the transfer matrix methods for the flexural vibrations of a beam including the effect of shear deflection and rotary inertia, and applying the spring transfer matrix taking into consideration the effect of longitudinal stiffness and rotational stiffness, we can discover the vibrational characteristics of the silo with the foundation. By applying this method, we can obtain the equivalent mass.

Lactic acid bacteria active during the fermentation of wheat silage in small scale silos

Wheat was ensiled and periodically analyzed for lactic acid bacteria present. Initially Lactobacillus plantarum, Leuconostoc mesenteroides, Lactobacillus cellobiosus and Streptococcus lactis predominated. After two to four days enterococci including S. faecium and S. bovis were present in high populations as well as Lactobacillus plantarum. It was concluded that mixed populations of enterococci and L. plantarum are active in the successful fermentation of wheat silage.