Lactic Acid Bacterial Inoculant Research Articles

Effect of Lentilactobacillus buchneri on Chemical and Microbial Compositions of Herba Leonuri (Leonurus japonicus Houtt.)-Contained Alfalfa Silage

Lactic acid bacteria (LAB) inoculants are commonly used in silage production, yet their effects on silage containing antimicrobial components, such as those found in Leonurus japonicus, remain less explored. Herein, the harvested alfalfa were thoroughly mixed with dried Leonurus japonicus Houtt. (LJH) at a ratio of 9:1 on a fresh weight basis and treated without (CK) or with a lactic acid bacterial inoculant (L; Lentilactobacillus buchneri). The mixtures were stored under anaerobic conditions in vacuum-sealed polyethylene bags for 30 days at ambient temperature. The L-treated silage exhibited high levels of water-soluble carbohydrates (4.98% dry matter (DM)) and acid detergent fiber (27.88% DM). Compared to that of treatment CK, treatment with L increased the acetic acid content of the silage, as a result of increased (p < 0.05) bacterial dominance and decreased (p < 0.05) bacterial richness indices (e.g., Pielou’s E, Shannon, and Simpson) in the pre-storage period. However, these changes gradually reduced as the storage length increased. Treatment L reshaped the bacterial community structure of silage, by increasing the prevalence of Lactobacillus and reducing relative abundances of Enterococcus and Weissella. However, the principal coordinate and Bray–Curtis index analyses illustrated that samples from the L-treated silages exhibited similarities to the CK samples post-fermentation. Overall, the effect of LJH on LAB was only observed in the later stages of fermentation, which did not sufficiently change the silage quality. Hence, using LJH in silage is vital for clean livestock production without compromising the function of LAB when mixed with alfalfa silage.

The effect of the addition of fermented natural lactic acid bacterial liquid and some lactic acid bacterial inoculants on alfalfa silage quality, in vitro digestibility and gas production

This study was conducted to evaluate the effect of adding fermented natural lactic acid bacteria (PFJ) obtained from different sources and some lactic acid bacteria inoculants to alfalfa (Medicago sativa L.) silage on fermentation, in vitro organic matter digestibility (IVOMD) and in vitro gas production. In the study, (i) pure alfalfa plant constituted the control group, whereas (ii) 2% molasses added group (iii) PFJ (3% molasses) prepared from alfalfa + 2% molasses to alfalfa plant, (iv) PFJ (3% molasses) prepared from meadow grass + 2% molasses alfalfa. plant, (v) PFJ (3% Molasses) prepared from maize + 2% molasses to alfalfa plant, (vi) homofermentative added group + 2% molasses to alfalfa plant, (vii) heterofermentative group + 2% molasses to alfalfa plant, added groups formed the trial groups. Homofermentative and heterofermentative LAB inoculants were added to alfalfa plant at the level of 108 cfu/kg. When the DM, CA, ADF, NDF, IVOMD, ME and CH4 values of the prepared silages were examined, the differences between the groups were found to be statistically significant. When the fermentation characteristics (pH, NH3-N, CO2, LA, AA, BA, mold) of the silages prepared by adding PFJ and some LAB inoculants to alfalfa plant, the differences between groups were found to be statistically significant. When examined in terms of all parameters, it was determined that the addition of PFJ (3% molasses) prepared from meadow grass + 2% molasses to alfalfa plant had positive effects on silage quality, fermentation characteristics and in vitro organic matter digestion.

PSIII-11 Effects of Inoculation of Alfalfa Hay with Pediococcus Pentosaceus and α-Amylase on Hay Temperature, Microbial Ecology, Nutrient Composition, and Feed Value

Abstract Haying in the Midwest is challenging, with excessive spring and early summer precipitation followed by unpredictable rain events throughout the growing months, forcing farmers to be innovative and resort to novel haying practices. High moisture haying with lactic acid bacterial (LAB) inoculants allows farmers to harvest earlier with less expenditure. This study examined how inoculating high-moisture alfalfa hay with Pediococcus pentosaceus and α-amylase (Magniva for Hay; Lallemand Animal Nutrition, Milwaukee, WI) affected hay temperature, microbial ecology, nutritional content, and feed value. Alfalfa was harvested at the late flowering stage and allowed to wilt in windrows for two days until the moisture level dropped to 20-25%, at which point half of the field was baled (20 bales) with the inoculant at 1.25 L ton-1, providing 1.0 × 106 cfu g-1 fresh forage of Pediococcus pentosaceus (NCIMB 12675) and 2.5 × 106 units of α-amylase (INOC). Uninoculated alfalfa baled at 15–18% moisture (20 bales) served as control (CON). The hay bales were stored under cover and sampled using a hay corer on days 0, 60, 120, and 180 to evaluate nutrient composition, microbial ecology, and feed value. Dallas Thermochron iButton sensors (Embedded Data Systems, Lawrenceburg, KY) were inserted into the center of hay bales during day 0 sampling (20 sensors per treatment) to measure the temperature every 4 h over 180 days. The core holes were air-tightened with alfalfa hay after installing the iButton sensors. SAS (SAS Institute Inc., 2012) mixed model technique was used to assess repeated measurements with treatment (T), day (D), and T × D effects. CON had greater LAB counts (log10 cfu g-1 DM) than INOC (7.45 vs. 7.11; P = 0.03) during storage. On days 0, 120, and 180 of storage, INOC had lower yeast counts (P < 0.02) than CON (T × D interaction). INOC exhibited higher core temperatures (P < 0.03) than CON on days 14, 21, and 28 of storage, peaking at 46.7°C on day 14. INOC reported lower DM than CON on days 60 and 120 of storage (P < 0.03). INOC had a higher CP concentration (18.0 vs. 16.9; P < 0.0001) than CON throughout storage. On days 60, 120, and 180 of storage, INOC had increased ADICP and NDICP (% DM) concentrations than CON (P < 0.05). Results indicated that inoculation of high moisture alfalfa hay with LAB inoculants is a viable alternative for farmers in the Midwest severely impacted by unpredictable weather events due to global warming. Further studies will provide detailed information on nutrient degradability and utilization for livestock production.

Effects of Xylanase and Bacterial Inoculants on In Vitro Rumen Fermentation Pattern of Seasonal Pasture Hay and Green Maize Based Silage

The present study was conducted to evaluate the effects of xylanase and bacterial inoculants on in vitro rumen fermentation pattern of seasonal pasture hay and green maize based silage. Different silages were prepared by using green maize fodder and seasonal pasture hay in the proportion of 10:0 & 7:3 ratio in plastic jars of 3 kg capacity by adding common salt @ 0.5%, urea @ 1% and molasses @ 1.5% in each silage with seven different treatments, viz., Control (only green maize), PH (green maize and seasonal pasture hay in 7:3 ratio), X (PH added with xylanase), LP (PH added with L. plantarum), LF (PH added with L. fermentum), LPLF (PH added with both bacterial inoculants) and XLPLF (PH added with xylanase and both bacterial inoculants). Xylanase, L. plantarum and L. fermentum were used @ 1500 IU/g, 1 x 106 cfu/g and 2 x 106 cfu/g, respectively. All silages were used for in vitro study after 45 days of ensiling. None of the additives affected rumen pH. IVDMD (in vitro dry matter degradability ) was found significantly (p<0.05) higher in X, XLPLF and LPLF silages. All additives significantly (p<0.01) increased IVOMD (in vitro organic matter degradability) except LF silage as compared to PH silage. Values for total gas production and TVFA (Total volatile fatty acids) production were significantly (p<0.001) increased during in vitro rumen fermentation and that of PF (partitioning factor) were significantly (p<0.001) decreased in all additives inoculated silages as compared to PH silage. Content of NH3-N (Ammonia nitrogen) was significantly (p<0.001) higher in LP silage and that of total N was significantly (p<0.001) higher in X, LP, XLPLF silages as compared to PH silage during in vitro study. It could be concluded that xylanase and lactic acid bacterial (LAB) inoculants improved rumen fermentation quality of silage. Among all additives, xylanase is the best silage additive to improve in vitro rumen fermentation pattern.

Fermentation Quality, In Vitro Digestibility, and Aerobic Stability of Total Mixed Ration Silage in Response to Varying Proportion Alfalfa Silage.

Simple SummaryEnsiling a total mixed ration (TMR) allows longer storage times for thoroughly mixed feed. In our previous study, we found that alfalfa silage could directly provide an acidic environment in fresh TMR and had a function comparable to that of lactic acid bacterial inoculants in improving fermentation quality during ensiling. However, the specific percentage of silage addition to the TMR has not been evaluated. In this study, we explored the effects of different proportions of alfalfa silage on the fermentation quality, in vitro digestibility, and aerobic stability of TMR silage and discussed the results in terms of the chemical composition of the feed. We found that the gradual development of an acidic environment during the ensiling process, which can be achieved with 40% alfalfa silage addition, can improve aerobic stability. However, the addition of 60% or 20% alfalfa silage might cause lower aerobic stability or clostridial spoilage in TMR silage. Our findings provide a more in-depth understanding of the effects of silage components on TMR silage and may guide farmers to apply a proper silage composition in rations to avoid the loss of feed value during storage or feeding stages.This study aimed to evaluate the effects of different proportions of alfalfa silage on the fermentation quality, in vitro digestibility, and aerobic stability of total mixed ration (TMR) silage. Three TMRs were prepared with different silage contents on a fresh matter basis: (1) 60% alfalfa silage (AS60), (2) 40% alfalfa silage (AS40), and (3) 20% alfalfa silage (AS20). The lactic acid in AS60 did not increase after 30 days of ensiling (p > 0.05). Butyric acid was detected in the AS20 group after 14 days of ensiling. The AS60 group showed significantly higher in vitro dry matter digestibility than the AS20 group (p < 0.05). The aerobic stability of TMR silage gradually increased with a decreasing percentage of alfalfa silage (p < 0.05). Unlike AS60, which directly gained an acidic environment from the alfalfa silage, AS40 developed a stable acidic environment during ensiling and further improved aerobic stability. However, when the percentage of alfalfa silage was reduced to 20%, a risk of clostridial spoilage occurred in the TMR silage. Therefore, the addition of 40% alfalfa silage to TMR is optimal and could achieve both good fermentation quality and considerable resistance to aerobic deterioration in TMR silage.

Modulation of Fermentation Quality and Metabolome in Co-ensiling of Sesbania cannabina and Sweet Sorghum by Lactic Acid Bacterial Inoculants.

Sesbania cannabina (SC) is a protein-rich roughage that thrives under moderate-severe saline-alkali (MSSA) soils with the potential to relieve the shortage of high nutritive forage. Sweet sorghum (SS) also tolerates MSSA soils and contains rich fermentable carbohydrates which could improve the fermentation quality in mixed silage. The present study investigated the silage quality, bacterial community, and metabolome in the mixed silage of SC and SS (SC-SS) with or without lactic acid bacterial (LAB) inoculants. Four ratios (10:0, 7:3, 5:5, and 3:7) of SC and SS were treated with sterile water or LAB inoculants (homofermentative Companilactobacillus farciminis and Lactiplantibacillus plantarum, and heterofermentative Lentilactobacillus buchneri and Lentilactobacillus hilgardii), which were analyzed after 60 days of ensiling. Results revealed that LAB inoculation improved the fermentation quality by increasing the lactic acid content and decreasing the ammonia nitrogen and butyric acid contents compared with the untreated group. LAB inoculation also raised the relative feed value by reducing indigestible fibers [e.g., neutral detergent fiber (NDF), acid detergent fiber, and hemicellulose]. Microbial and metabolomic analysis indicated that LAB inoculants could modify the bacterial community and metabolome of SC-SS silage. In co-ensiling samples except for SC alone silage, L. buchneri and L. hilgardii were the dominant species. Metabolites with bioactivities like anti-inflammatory, antioxidant, antimicrobial, and anti-tumor were upregulated with LAB inoculation. Furthermore, correlation analysis demonstrated that active metabolites (e.g., glycitin, glabrene, alnustone, etc.) were positively correlated with L. buchneri, while tripeptides (e.g., SPK, LLK, LPH, etc.) were positively correlated with L. hilgardii. Adequately describing the SC-SS silage by multi-omics approach might deepen our understanding of complicated biological processes underlying feature silages fermentation. Moreover, it may also contribute to screening of targeted functional strains for MSSA-tolerating forage to improve silage quality and promote livestock production.

Effects of Lactic Acid Bacterial Inoculants on Fermentation Quality, Bacterial Community, and Mycotoxins of Alfalfa Silage under Vacuum or Nonvacuum Treatment

To investigate the effects of lactic acid bacterial (LAB) inoculants and vacuuming on the fermentation quality and bacterial community, alfalfas were ensiled with or without a commercial LAB YX or Lactobacillus plantarum strain ZZUA493 for 10, 30, 60, and 90 days while undergoing either vacuum (V) or nonvacuum (NV) treatment. At 90 days, analysis of the microbial community by high-throughput sequencing was performed, and contents of aflatoxin B1 and deoxynivalenol (DON) mycotoxins in alfalfa silage were determined. In all inoculated alfalfa silage, irrespective of V or NV treatment, lactic acid (LA) content increased, pH (p < 0.05), and ammonia nitrogen (p < 0.05) content decreased, and no butyric acid was detected. Lactobacillus or Pediococcus became the dominant genus, and the abundance of Garciella decreased in alfalfa silage with the addition of either inoculant. The LAB inoculants YX and ZZUA493 helped reduce the mycotoxin content in alfalfa silage. The abundance of Garciella in the control and DON content in all alfalfa silage groups were higher (p < 0.05) in NV than V. In summary, LAB inoculants and vacuuming had a positive influence on alfalfa silage quality, and LAB inoculants were effective in reducing mycotoxins in silage alfalfa.

Effects of formic acid and lactic acid bacteria inoculant on main summer crop silages in Korea.

To improve the fermentation quality of silage and reduce the nutrients loss of raw materials during the ensiling process, silage additives are widely used. The effect of additives on silage is also affected by the species of crop. Therefore, this study was designed to explore the effects of formic acid (FA) and lactic acid bacterial inoculant on the quality of main summer crop silage. The experiment was consisted on split-plot design with three replications. The experiment used the main summer forage crops of proso millet (“Geumsilchal”), silage corn (“Gwangpyeongok”), and a sorghum-sudangrass hybrid (“Turbo-gold”). Treatments included silage with Lactic acid bacterial Inoculant (Lactobacillus plantarum [LP], 1.0 × 106 CFU/g fresh matter), with FA (98%, 5 mL/kg), and a control (C, without additive). All silages were stored for 60 days after preparation. All additives significantly increased the crude protein content and in vitro dry matter digestibility (IVDMD) of the silages and also reduced the content of ammonia nitrogen (NH3-N) and pH. Corn had the highest content of IVDMD, total digestible nutrients and relative feed value among silages. Compared with the control, irrespective of whether FA or LP was added, the water soluble carbohydrate (WSC) of three crops was largely preserved and the WSC content in the proso millet treated with FA was the highest. The treatment of LP significantly increased the lactic acid content of the all silage, while the use of FA significantly increased the content of acetic acid (p < 0.05). The highest count of lactic acid bacteria (LAB) was detected in the LP treatment of corn. In all FA treatment groups, the total microorganism and mold numbers were significantly lower than those of the control and LP groups (p < 0.05). In conclusion, both additives improved the fermentation quality and nutritional composition of the main summer forage crops. The application of FA effectively inhibited the fermentation of the three crops, whereas LAB promoted fermentation. So, both FA and LP can improve the quality of various species of silage.

PSVIII-25 Evaluation of different ensiling methods of the residual material from edamame soybean processing

Abstract This research evaluated the storage and feeding value of residual from edamame soybean production on a laboratory scale. Two types of residual or waste material (waste from harvesting, and waste from processing stored material) were ensiled in 500-gram silos (≥ 3 silos per treatment). Material from harvest (a single trip) was ensiled either without wilting (fresh, 71% moisture) or after wilting to a target of 60% moisture; while material from processing (4 replicate trips) was ensiled at 80 (fresh), and targets of 65, 50, and 35% moisture; material at each targeted moisture level was ensiled with and without a commercial lactic acid bacterial inoculant (Lactobacillus buchneri). Dry matter loss and pH were determined after 42 (harvest waste) or 50 (processing waste) days of ensiling. Pre-ensiled processing waste material was 57% NDF, 39.4% ADF, 12.1% CP. and 8.1% ash (average of material from 3 trips). For harvest waste, there was an inoculant by ensiling DM interaction (P = 0.05) for post-ensiling pH. Ensiled fresh material without inoculant had the lowest pH (5.3) and fresh material ensiled with inoculant had a greater pH (5.5) but both were lower than either inoculant treatments using dryer material (6.5). Recoveries of DM after ensiling tended to be greater with the inoculant (89.8 vs. 86.2%). For processing waste, there was a quadratic effect of ensiling DM (P &amp;lt; 0.01), with post-ensiling pH being lowest for fresh and 22% DM (4.4 and 4.6) then increasing to 5.2 and 6.7 when ensiled at 46 and 74% DM. There was no effect of inoculant or an inoculant by ensiling DM on post-ensiling pH. As expected, ensiling wetter material resulted in a lower post-ensiling pH for both residual materials. Adding a silage inoculant had minimal effects on pH but tended to increase the recoveries of DM from the harvest waste.

Dynamics of Bacterial Community and Fermentation Quality during Ensiling of Wilted and Unwilted Moringa oleifera Leaf Silage with or without Lactic Acid Bacterial Inoculants.

To investigate the effects of wilting and lactic acid bacterial inoculants on the fermentation quality and bacterial community of Moringa oleifera leaf silage, fresh and wilted M. oleifera leaves were ensiled with or without Lactobacillus farciminis LF or Lactococcus lactis LL for 1, 7, 14, 30, and 60 days. The results showed that wilting, inoculants, and their interaction exerted significant (P < 0.05) effects on the fermentation characteristics covering dry matter loss, pH value, lactic acid bacterial number, the ratio of lactic acid to acetic acid, and the relative abundances of bacteria, like for species of Lactobacillus, Lactococcus, Pediococcus, Enterococcus, Leuconostoc, and Enterobacter Both LF and LL improved the fermentation quality of wilted and unwilted M. oleifera leaf silage by accelerating lactic acid production and pH decline, decreasing dry matter loss, and inhibiting yeast and coliform bacterial growth through the whole fermentation process. During ensiling, the abundances of Lactococcus, Enterococcus, and Leuconostoc spp. increased from day 1 to day 7 and then declined sharply from day 7 to day 14. Members of these genera and Enterobacter were inhibited, whereas Lactobacillus spp. were enhanced by these two lactic acid bacterial inoculants. The relative abundances of Enterobacter, Enterococcus, and Pediococcus spp. in inoculated silages were relatively low during the whole ensiling process. A lower abundance of Enterobacter spp. was observed in wilted silages than in unwilted silages. In summary, wilting and lactic acid bacterial inoculants had an influence on bacterial community and the fermentation process; LF and LL improved the fermentation quality of wilted and unwilted M. oleifera leaf silage.IMPORTANCEMoringa oleifera leaf is a high-quality feed source for livestock and is increasingly used all over the world. Ensiling might be an effective method for preservation of the leaves. In the practice of silage making, lactic acid bacterial inoculants and wilting are commonly used to improve nutrition preservation. Monitoring the changes in a bacterial community during fermentation gives an insight into understanding and improving the ensiling process. Our results suggest that wilting and lactic acid bacterial inoculants had an influence on the bacterial community and fermentation process of M. oleifera leaf silage. Wilting showed positive effects on silage fermentation by decreasing the abundance of Enterobacter spp., while LF and LL improved the fermentation quality by inhibiting Enterobacter spp. and enhancing Lactobacillus spp. Both LF and LL accelerated the ensiling process from cocci (like Lactococcus, Enterococcus, and Leuconostoc spp.) to lactobacilli.

Potential of Ensiling Sorghum without Grain Pretreated with Enzymes or Bacterial Inoculants

Silage is an alternative product from sorghum [Sorghum bicolor (L.) Moench] that does not make grain due to drought, disease, or pests. The objective of this experiment was to determine nutritive value and fermentation characteristics of silage made from sorghum without grain and evaluate the impact of pretreatment with fibrolytic enzymes or lactic acid bacterial inoculants. Triplicate plots (4 rows ×12.2 m) of four sorghum cultivars (Dairy Master, PS 747, Silo 700D, and MMR 381/73 [MMR]) were planted in a completely randomized block design field trial at three locations (Beeville, College Station, and Kingsville, TX). At the mid‐dough stage, sorghum was harvested and inflorescences were removed, chopped, and separated into three (5 kg) subsamples. Each subsample was treated with either distilled water (control), fibrolytic enzyme, or bacterial inoculant and ensiled for 120 d. Pre‐ensiled sorghum without grain had similar nutritive value, except Dairy Master had 25% lower crude protein and 30% lower lignin concentrations. After ensiling, water‐soluble carbohydrate concentration was lowest and crude protein concentration was greatest for MMR silage, which also had the greatest acetate concentration and lactate/acetate ratio. Silage treated with either lactic acid bacterial inoculant or fibrolytic enzyme had 40% greater water‐soluble carbohydrate concentration. Silage treated with fibrolytic enzyme had 8% lower neutral detergent fiber and acid detergent fiber concentrations than untreated silage, and treated silage had lower pH than untreated silage. The pH of all silage was &lt;4.0, and pretreatment did not improve silage fermentation characteristics or increase aerobic stability. The cultivar was more influential to the resulting silage product than pretreatment in this experiment.

Bakteriyal İnokulant ve Organik Asit Kullanımının Düşük Kuru Maddeli Küçük Balya Mısır Silajlarının Aerobik Stabilite ve Yem Değeri Üzerine Etkisi

Bu araştırma, bir homofermantatif laktik asit bakteri (LAB) inokulantının ve formik asit temeline dayalı bir koruyucunun (FAT) düşük kuru maddeli (KM) küçük balya mısır (Zea mays L.) silajının aerobik stabilite ve yem değeri üzerine olan etkisinin belirlenmesi amacı ile yürütülmüştür. Mısır süt olum döneminde hasat edilmiş (%26,4 KM) ve yaklaşık 2,0 cm boyutunda parçalanmıştır. Araştırmada LAB inokulantı olarak Pioneer 1132 H/M F, FAT olarak KemiSile 2000 adlı ticari ürünler kullanılmıştır. Katkı maddeleri mısıra sırasıyla, LAB 106 cfu/g; FAT 3, 4 ve 5 g/kg; LAB+FAT 106 cfu/g+3 g/kg, 106 cfu/g+4 g/kg, 106 cfu/g+5 g/kg düzeyinde katılmıştır. Kontrol ve katkı maddeleri ile muamele edilen mısır her uygulama için 3‘er tekerrür olmak üzere 30 kg kapasiteli plastik torbalara silolanmıştır. Silolamadan 60 gün sonra açılan silajlarda kimyasal ve mikrobiyolojik analizler yapılmış, silajlara 5 gün süre ile aerobik stabilite testi uygulanmış ve ayrıca silajların in vitro organik madde (OM) sindirilebilirlikleri ve metabolik enerji (ME) değerleri saptanmıştır. Sonuç olarak, homofermantatif LAB inokulantı, FAT ve LAB+FAT kombinasyonu düşük KM‘ li mısır silajlarının aerobik stabilitelerini etkilemezken, in vitro OM sindirilebilirliklerini ve ME değerlerini düşürmüştür.

Development of a new lactic acid bacterial inoculant for fresh rice straw silage.

ObjectiveEffects of newly isolated Lactobacillus plantarum on the fermentation and chemical composition of fresh rice straw silage was evaluated in this study.MethodsLactic acid bacteria (LAB) from good crop silage were screened by growing them in MRS broth and a minimal medium with low carbohydrate content. Selected LAB (LAB 1821) were Gram-positive, rods, catalase negative, and were identified to be Lactobacillus plantarum based on their biochemical characteristics and a 16S rRNA analysis. Fresh rice straw was ensiled with two isolated LAB (1821 and 1841), two commercial inoculants (HM/F and P1132) and no additive as a control.ResultsAfter 2 months of storage at ambient temperature, rice straw silages treated with additives were well-preserved, the pH values and butyric and acetic acid contents were lower, and the lactic acid content and lactic/acetic acid ratio were higher than those in the control (p<0.05). Acidity (pH) was lowest, and lactic acid highest, in 1821-treated silage (p<0.05). The NH3-N content decreased significantly in inoculant-treated silage (p<0.05) and the NH3-N content in 1821-treated silage was lowest among the treatments. The dry matter (DM) content of the control silage was lower than that of fresh rice straw (p<0.05), while that of the 1841- and p1174-inoculant-treated silages was significantly higher than that of HM/F-treated silage. Microbial additives did not have any significant (p>0.05) effect on acid detergent fiber or neutral detergent fiber contents. Crude protein (CP) content and in vitro DM digestibility (IVDMD) increased after inoculation of LAB 1821 (p<0.05).ConclusionLAB 1821 increased the CP, IVDMD, lactic acid content and ratio of lactic acid to acetic acid in rice straw silage and decreased the pH, acetic acid, NH3-N, and butyric acid contents. Therefore, adding LAB 1821 improved the fermentation quality and feed value of rice straw silage.

Dynamics of microbial community during ensiling direct-cut alfalfa with and without LAB inoculant and sugar.

To gain deeper insights into the clostridial community dynamics and chemical transformations during the ensiling of alfalfa. Direct-cut alfalfa silage (with the dry matter content of 240gkg-1 ) was prepared with or without the addition of a lactic acid bacterial inoculant and sucrose. Silages were sampled at 0, 3, 7, 14, 28 and 56days after ensiling and their bacterial community was determined using high-throughput sequencing with a special focus on the clostridial community. A clostridial fermentation occurred in the control silage, with high contents of acetic acid, butyric acid and ammonia nitrogen and Clostridia counts; while the inoculated silage was well preserved, with low pH and high lactic acid content. Lactic acid bacteria dominated the bacterial community during the ensiling process. In the control silage, Weissella confusa, Lactobacillus brevis, Enterococcus mundtii and Pediococcus acidilactici were identified at the beginning of the fermentation. Thereafter, W. confusa, Lactobacillus helsingborgensis and Bifidobacterium asteroides appeared and quickly prevailed. In the inoculated silage, Lactobacillus plantarum dominated the whole ensiling process. The genus Clostridium dominated the clostridial community, and was depressed with the inoculated treatment. Clostridium perfringens, Garciella sp. and Clostridium baratii were the main initiators of the clostridial fermentation of the control silage, while Clostridium tyrobutyricum became the most abundant Clostridia with prolonged ensiling. Overall in the inoculated silage, little changes in the clostridial community were observed throughout the ensiling period. Treating alfalfa silage with a homolactic acid-based bacterial inoculant prevented a clostridial fermentation resulting in more efficient fermentation. Distinct changes in the bacterial community with a special focus on the clostridial community were associated with the development of the clostridial fermentation during the ensiling of alfalfa. High-throughput sequencing based on a novel Clostridia-specific primer set proved a potentially useful tool to study the clostridial community dynamics, and could aid to elucidate the mechanism by which the clostridial fermentation develops during the ensiling of alfalfa.

Effects of lines and inoculants on nutritive value and production costs of triticale silages

The current study was undertaken to investigate the ensilage characteristics in triticale lines treated by inoculants and their interaction on fermentation metabolites and rumen degradability. Costs were estimated for growing and feeding whole-crop triticale lines for animal production. Triticale hybrids were harvested at the dough stage of maturity (38% dry matter, DM). Plants were chopped approximately 2 cm after harvest and then treated with inoculants and were ensiled in 1.5-L mini laboratory silos. Two lactic acid bacterial inoculants with enzymes (LAB+enzymes I: Pediococcus acidilactici, Lactobacillus plantarum, and Streptococcus faecium with cellulase, hemicellulase, pentosanase, and amylase; LAB+enzyme II: P. acidilactici, L. plantarum, and amylase) were used as silage additives. Inoculants were applied at 1.5 × 105 cfu/g chopped fresh material. Silages with no additive served as the control. Four jars per treatment were sampled on day 60 after ensiling for chemical and microbiological analysis. At the end of the ensiling period (60 day), the silages were subjected to an aerobic stability test. The nutrient degradability of silages was determined in situ. Overall, there were no obvious interactions between triticale lines and the treatments for any of the parameters measured. The fermentation and nutritive value of silages were affected by treatments. LAB+enzymes increased the concentrations of lactic acid of the triticale silages and decreased the concentrations of butyric acid, total alcohols, and ammonia-N. Under aerobic conditions, LAB+enzyme treated silages had lower pH, CO2 production, and number of yeasts. Fibrous fractions were decreased with the application of LAB+enzymes. The 48 h in situ organic matter, DM, and neutral detergent fiber digestibility of the silages were enhanced by treatments. Addition LAB+enzymes to dough stage triticale silage reduces proteolysis; the inoculant possess antimicrobial properties and improves fermentation and nutritional value. The economic results are favorable financially for growing winter triticale as an animal feed in Mediterranean-type climates.

An invitro model to study interactions between Escherichia coli and lactic acid bacterial inoculants for silage in rumen fluid.

Previous studies have shown that silages treated with lactic acid bacteria (LAB) inoculants enhance ruminants' performance. The objective of the current experiments was to develop an invitro model to study interactions between LAB silage inoculants and inoculated silages and Escherichia coli (EC) in rumen fluid (RF). Our hypothesis was that some inoculants inhibit EC in RF. For that purpose buffered RF was incubated under anaerobic conditions at 39°C with commercial strains of LAB silage inoculants or with laboratory corn and wheat silages treated with these LAB, an EC strain and with various ruminant feed ingredients. The EC strain was originally isolated from cattle manure and tagged with a plasmid expressing the green fluorescence protein and kanamycin and streptomycin resistance. Results indicate that the LAB or the treated silages did not suppress EC numbers in the RF. When the pH of the RF decreased below 5·0 the EC disappeared. We conclude that both LAB inoculants for silage and EC survived in RF for several days; however, the inoculants and silages treated with such inoculants did not inhibit EC in RF invitro. Forage crops, silage and hay are initial stages of the food chain for humans. Cattle harbours and sheds enterobacteria regularly, some strains of which are pathogens. These can contaminate forage crops through field fertilization with cattle manure. The objective of this study was to develop an invitro model to test whether lactic acid bacteria, which are used in silage inoculants, alone or in treated silages can inhibit Escherichia coli in rumen fluid. This study presents safety aspects and it is also part of a broad research effort aimed at finding out how LAB silage inoculants and inoculated silages enhance ruminant performance or exert probiotic effects in ruminants.

Ensiling corn silage with different levels of a multi-species lactic acid bacteria inoculant

A multi-species lactic acid bacterial inoculant (Lactisil maize, LM) was applied to whole-crop corn at different maturities in laboratory silos, to evaluate its effects on biochemical characteristics and aerobic stability. The corn crop was harvested at hard dough (HD, 253.1 g/DM kg), one-third milkline (ML, 293.7 g/DM kg) and one-third milkline with a killing frost (MLF, 297.6 g/DM kg). Crops were chopped to a 2.5-cm theoretical cut length, subsampled and treated with two levels of inoculant (LB1 = 1.5 × 105 cfu/g forage, LB2 = 3 × 105 cfu/g forage) or untreated (WO). The chemical composition of MLF crops was very similar to that of ML crops. However, lower (P &lt; 0.01) numbers of lactic acid bacteria and higher numbers of yeast were enumerated in MLF than in ML crops. Higher percentages of DM and neutral detergent fibre and higher pH, but lower (P &lt; 0.01) concentrations of water soluble carbohydrate and crude protein were measured in ML and MLF crops than in HD crops. Application of the inoculant increased (P &lt; 0.01) concentrations of volatile fatty acids, neutral detergent fibre and acid detergent fibre in silages. Lactic acid concentration increased (P &lt; 0.01) in HD treatments with an increasing level of inoculant. In contrast, the highest (P &lt; 0.01) lactic acid concentration was measured in LB1 treatment compared with WO and LB2 in ML and MLF silages. Silages prepared from ML and MLF crops had higher (P &lt; 0.01) lactic and acetic acid concentrations but lower (P &lt; 0.01) butyric acid concentrations than did those prepared from HD. The pH in LB1 and LB2 silages was higher (P &lt; 0.01) than that measured in WO silages. Aerobic stability was not influenced by inoculant treatment but low-DM silages were more (P &lt; 0.01) resistant to spoilage. Frost-killed corn crops had a good potential to produce well fermented silage. Using LM resulted in silages with slightly higher fermentation products but it failed to improve aerobic stability of silage after 120 days of ensiling. These results indicated that inoculation of corn crops with LM for a short-duration ensilage period cannot enhance aerobic stability of silages due to insufficient acetic acid production from lactic acid conversion.

Silage fermentation characteristics of three common grassland species in response to advancing stage of maturity and additive application

AbstractThis study investigated the effects of advancing stage of maturity and additive treatment on the fermentation characteristics of three common grassland species. Perennial ryegrass (PRG; Lolium perenne L., var. Gandalf), timothy (Phleum pratense L., var. Erecta) and red clover (Trifolium pratense L., var. Merviot) were harvested at three dates in the primary growth (11 May, 8 June and 6 July; Harvests 1–3) and ensiled with the following additive treatments: (1) control (i.e. no treatment), (2) formic acid‐based additive, (3) homofermentative lactic acid bacterial (LAB) inoculant and (4) heterofermentative LAB inoculant. Additive application to the PRG (irrespective of harvest date), the late‐harvest timothy (Harvest 3) and the red clover (Harvests 2 and 3) herbages had little impact on silage fermentation characteristics, where a lactic acid dominant fermentation already prevailed. However, the application of the formic acid‐based additive to the Harvest 1 and 2 timothy and Harvest 1 red clover herbages, where the silage fermentation characteristics were poorer, resulted in an increase in the proportion of lactic acid in total fermentation products and a decrease in pH. In contrast, the heterofermentative LAB inoculant had a negative impact on silage fermentation characteristics where a poor preservation prevailed in the corresponding control silage.

Changes in ruminal bacterial community composition following feeding of alfalfa ensiled with a lactic acid bacterial inoculant

Some silage inoculants help to improve silage quality and promote an increase in milk production, possibly through altering the rumen microflora. We hypothesized that rumen bacterial community composition (BCC) would be different in cows fed alfalfa ensiled with the inoculant Lactobacillus plantarum MTD/1 (LP) compared with those fed alfalfa ensiled without the inoculant (Ctrl). Eight ruminally cannulated Holstein cows were allotted to 2 diets (Ctrl or LP) in a double crossover design with four 28-d periods. Diets were formulated to contain (% dry matter basis) 28.0% neutral detergent fiber and 16.2% crude protein, and contained alfalfa silage, 50.9; corn silage, 20.6; high-moisture shelled corn, 21.4; soy hulls, 4.7; plus minerals and vitamins, 2.4. Ruminal digesta were collected just before feeding on 3 consecutive days near the end of each period, and were separated into solid and liquid phases. Microbial DNA was extracted from each phase, amplified by PCR using domain-level bacterial primers, and subjected to automated ribosomal intergenic spacer analysis. The pH was 4.56 and 4.86 and the lactate-to-acetate ratio 9.8 and 4.4, respectively, for the treated and untreated alfalfa silages. Dry matter intakes and milk production data were not influenced by diets but showed a cow effect. Total volatile fatty acids (mM) tended to be greater for LP compared with Ctrl. Individual volatile fatty acids were not influenced by diets but showed a significant cow effect. Ruminal acetate (mol/100mol) and acetate-to-propionate ratio were lower and propionate (mol/100mol) greater for the 2 milk fat-depressed (MFD; <3.2% fat content) cows compared with the other 6 cows. Correspondence analysis of the 265 peaks in the automated ribosomal intergenic spacer analysis profile across the 188 samples revealed that the first 2 components contributed 7.1 and 3.8% to the total variation in the profile. The ordination points representing the liquid and solid phases clustered separately, indicating that these phases differed in BCC. The analysis of similarity data showed differences between Ctrl and LP. The lactic acid bacterial counts (log10 cfu/g of wet silage) were 3.94 and 4.53 for the untreated and treated silage, respectively, at ensiling. The relative population size (RPS) of L. plantarum, determined by real-time PCR of 16S rRNA gene copies, was greater in LP compared with Ctrl. The ordination points corresponding to certain individual cows clustered separately, and the most distinctive bacterial communities were those associated with MFD cows. The RPS of Megasphaera elsdenii was greater in 1 of the 2 MFD cows, although mean RPS of M. elsdenii did not differ between the treatments. In addition to the differences in rumen BCC between LP and Ctrl, MFD cows also displayed differences in BCC compared with cows with normal milk fat yield.

Effects of stage of maturity at harvest, wilting and LAB inoculant on aerobic stability of wheat silages

The objective was to study effects of cultivar, stage of maturity at harvest, wilting, and addition of lactic acid bacterial (LAB) inoculant at ensiling, and their interactions, on the aerobic stability of wheat silages. Wheat of two cultivars, harvested at the flowering or the milk stage of maturity were ensiled in mini-silos, either directly after cutting (DC) or after wilting (W). After 2–7 months of storage, silages were subjected to a 7-day aerobic stability test during which changes in chemical composition, dry matter (DM) and neutral detergent fiber (aNDF) digestibility, and temperature, as well as DM losses and CO 2 production, were measured. Silages from wheat cultivar BH were relatively dry (DM between 287 and 430 g/kg) and were mostly stable upon aerobic exposure. The flowering wheat of cultivar Galil was moister (DM of 199 g/kg), and the DC silages were stable upon aerobic exposure. Silages of the wilted flowering wheat (DM of 370 g/kg) spoiled and after 4 and 7 days, produced 15 and 76 g/kg DM CO 2, respectively. Silages from the milk stage of this cultivar, both DC and W were unstable, and a homofermentative LAB enhanced aerobic spoilage. Factorial analysis of variance was applied to the results with cultivar, stage of maturity, wilting and inoculant as main effects, as well as their interactions. Cultivar and LAB inoculant had effects on silage composition and aerobic stability, with stage of maturity having an effect on aerobic losses, whereas wilting did not have effects on aerobic spoilage indicators. The inoculant enhanced CO 2 production in the silages prepared from the DC wheat of the flowering and milk stages, as compared with the respective non-inoculated control silages which contained high concentrations of VFA. However, in the wilted silages which contained less VFA, both control and inoculated silages deteriorated similarly with time of exposure to air.