Fermentation Pattern Research Articles

Effect of Molasses Addition at Ensiling on Ruminal <i>In Situ</i> Dry Matter and Nutrient Degradation of Whole-Plant Soybean Silage Harvested at Different Phenological Stages

Whole-plant soybean ensiling has limitations and challenges that affect silage fermentation patterns and reduce ruminal nutrient degradation. Perhaps either the addition of molasses at ensiling or harvesting at different phenological stages has the potential to enhance whole-plant soybean silage (WSS) ruminal degradation. This experiment was a completely randomized design with a 3 × 2 factorial arrangement of treatments evaluating the effects of molasses (0 and 40 g/kg fresh forage) and phenological stage (R5: beginning seed, R6: full seed, and R7: beginning maturity) on ruminal in situ degradation. Molasses increased effective ruminal degradability (ERD) of dry matter (DM) regardless of the phenological stage and increased ERD of crude protein at R5 and R6. The addition of molasses at later phenological stages increased ERD of neutral detergent fiber (NDF). There was a molasses × phenological stage interaction effect with greater fractions A and B of NDF at R7 and R5, respectively, but lower undegraded NDF at R5 and R6 with molasses addition. Although the benefits of adding molasses were more pronounced in R5 and R6, adding molasses to whole-plant soybean at ensiling is recommended regardless of phenological stage. Increasing the proportion of digestible nutrients at harvesting either by harvesting at later phenological stages or the addition of molasses is a powerful strategy to manage ruminal degradation of DM and nutrients in WSS.

Supplementing Glycerol to Inoculum Induces Changes in pH, SCFA Profiles, and Microbiota Composition in In-Vitro Batch Fermentation

Glycerol was generally added to the inoculum as a cryoprotectant. However, it was also a suitable substrate for microbial fermentation, which may produce more SCFAs, thereby decreased pH of the fermentation broth. This study investigated the effect of supplementing glycerol to inoculum on in vitro fermentation and whether an enhanced buffer capacity of medium could maintain the pH stability during in vitro batch fermentation, subsequently improving the accuracy of short chain fatty acids (SCFAs) determination, especially propionate. Two ileal digesta were fermented by pig fecal inoculum with or without glycerol (served as anti-frozen inoculum or frozen inoculum) in standard buffer or enhanced buffer solution (served as normal or modified medium). Along with the fermentation, adding glycerol decreased the pH of fermentation broth (p < 0.05). However, modified medium could alleviate the pH decrement compared with normal medium (p < 0.05). The concentration of total propionic acid production was much higher than that of other SCFAs in anti-frozen inoculum fermentation at 24 and 36 h, thereby increasing the variation (SD) of net production of propionate. The α-diversity analysis showed that adding glycerol decreased Chao1 and Shannon index under normal medium fermentation (p < 0.05) compared to modified medium (p < 0.05) along with fermentation. PCoA showed that all groups were clustered differently (p < 0.01). Adding glycerol improved the relative abundances of Firmicutes, Anaerovibrio, unclassified_f_Selenomonadaceae, and decreased the relative abundance of Proteobacteria (p < 0.05). The relative abundances of Firmicutes, such as Lactobacillus, Blautia and Eubacterium_Ruminantium_group in modified medium with frozen inoculum fermentation were higher than (p < 0.05) those in normal medium at 36 h of incubation. These results showed that adding glycerol in inoculum changed the fermentation patterns, regardless of substrate and medium, and suggested fermentation using frozen inoculum with modified medium could maintain stability of pH, improve the accuracy of SCFA determination, as well as maintain a balanced microbial community.

Isolation, Characterization and Acid/Alkaline Tolerance of Lactic Acid Bacteria Present in Fermented Rye, Wheat, Oat and Barley

Objective: This study determined the lactic acid bacteria (LAB) present in fermented rye, wheat, oat and barley grains, and evaluated their survival in simulated gastric juice and pancreatic juice.
 Methods: Samples of rye, wheat, oat and barley grains were fermented for 72 hours at room temperature. Lactic acid bacteria (LAB) strains were isolated using MRS agar and were enumerated. Isolated LAB strains were cultured with MRS broth and the fermentation patterns of the isolated strains were characterized using API 50 CH kit (Biomerieux, France). Each isolated LAB strain was exposed to simulated gastric juice at pH of 2.0 for 80 minutes at 370C, followed by exposure to simulated pancreatic juice at pH of 8.0 for 120 minutes at 370C. Aliquots were taken at 0 minute and 80 minutes at pH of 2.0 and 0 minutes and 120 minutes at pH of 8.0 for enumeration of LAB strains.
 Results: The total LAB cell count ranged from 6.6 * 108 ± 11 cfu/ml in the rye sample to 9.5*109 ± 7 cfu/ml in the oat sample. 13 LAB strains were isolated from the four selected cereal grains and were characterized as six strains of Lactobacillus plantarum1, five strains of L. brevis 1 and one strain each of L. collinoides and Leuconostoc citreum. All the isolated LAB strains from the four selected cereals survived in the simulated gastric juice at pH of 2.0 (before and after incubation at 0min and 80a min) and after addition of simulated pancreatic juice at pH of 8.0 (before and after incubation at 80b min and 200 min respectively). The mean viable counts of all the strains ranged from 2.0 *108 in R3 at 80b min to 1.54 * 1010 in B4 at 80b minutes.
 Conclusion: LAB associated with fermentation of rye, wheat, oat and barley grains are likely to survive transport through the harsh acidic and alkaline conditions of the GIT.

Impact of Citrus Pulp or Inulin on Intestinal Microbiota and Metabolites, Barrier, and Immune Function of Weaned Piglets.

We investigated the use of citrus pulp (CP) as a novel prebiotic capable of exerting microbiota and immunomodulating capacities to alleviate weaning stress. Inulin (IN), a well-known prebiotic, was used for comparison. Hundred and 28 male weaned piglets of 21 days old were assigned to 32 pens of 4 piglets each. Piglets were assigned to one of the four treatments, i.e., control, IN supplemented at 0.2% (IN0.2%), and CP supplemented either at 0.2% (CP0.2%) or at 2% (CP2%). On d10–11 and d31–32 post-weaning, one pig per pen was euthanized for intestinal sampling to evaluate the growth performance, chyme characteristics, small intestinal morphology, colonic inflammatory response and barrier integrity, metabolite profiles [gas chromatography-mass spectrometry (GC-MS), and liquid chromatography-mass spectrometry (LC-MS)], and microbial populations. The IN treatment and the two CP treatments induced higher small intestinal villus height to crypt depth ratios in comparison with the control diet at both sampling times. All treatments decreased acidic goblet cell absolute counts in the crypts in comparison to the control diet of the duodenum on d10–11 and d31–32. The gene expression of β-defensin 2 was downregulated in colonic tissues following the IN and CP2% inclusion on d31–32. On d31–32, piglets fed with IN and CP0.2% showed lower mRNA levels of occludin and claudin-3, respectively. Not surprisingly, flavonoids were observed in the colon in the CP treatments. Increased colonic acetate proportions on d10–11, at the expense of branched-chain fatty acid (BCFA) levels, were observed following the CP2% supplementation compared to the control diet, inferring a reduction of proteolytic fermentation in the hindgut. The beneficial microbial community Faecalibacterium spp. was promoted in the colon of piglets fed with CP2% on d10–11 (p = 0.04; false discovery rate (FDR) non-significant) and on d31–32 (p = 0.03; FDR non-significant) in comparison with the control diet. Additionally, on d31–32, CP2% increased the relative abundance of Megasphaera spp. compared to control values (p = 0.03; FDR non-significant). In conclusion, CP2% promoted the growth of beneficial bacterial communities in both post-weaning time points, modulating colonic fermentation patterns in the colon. The effects of CP supplementation were similar to those of IN and showed the potential as a beneficial feed supplement to alleviate weaning stress.

Regulation of CcpA on the growth and organic acid production characteristics of ruminal Streptococcus bovis at different pH

BackgroundCatabolite control protein A (CcpA) regulates the transcription of lactate dehydrogenase and pyruvate formate-lyase in Streptococcus bovis, but knowledge of its role in response to different pH is still limited. In this study, a ccpA-knockout strain of S. bovis S1 was constructed and then used to examine the effects of ccpA gene deletion on the growth and fermentation characteristics of S. bovis S1 at pH 5.5 or 6.5.ResultsThere was a significant interaction between strain and pH for the maximum specific growth rate (μmax) and growth lag period (λ), which caused a lowest μmax and a longest λ in ccpA-knockout strain at pH 5.5. Deletion of ccpA decreased the concentration and molar percentage of lactic acid, while increased those of formic acid. Strains at pH 5.5 had decreased concentrations of lactic acid and formic acid compared to pH 6.5. The significant interaction between strain and pH caused the highest production of total organic acids and acetic acid in ccpA-knockout strain at pH 6.5. The activities of α-amylase and lactate dehydrogenase decreased in ccpA-knockout strain compared to the wild-type strain, and increased at pH 5.5 compared to pH 6.5. There was a significant interaction between strain and pH for the activity of acetate kinase, which was the highest in the ccpA-knockout strain at pH 6.5. The expression of pyruvate formate-lyase and acetate kinase was higher in the ccpA-knockout strain compared to wild-type strain. The lower pH improved the relative expression of pyruvate formate-lyase, while had no effect on the relative expression of acetate kinase. The strain × pH interaction was significant for the relative expression of lactate dehydrogenase and α-amylase, both of which were highest in the wild-type strain at pH 5.5 and lowest in the ccpA-knockout strain at pH 6.5.ConclusionsOverall, low pH inhibited the growth of S. bovis S1, but did not affect the fermentation pattern. CcpA regulated S. bovis S1 growth and organic acid fermentation pattern. Moreover, there seemed to be an interaction effect between pH and ccpA deletion on regulating the growth and organic acids production of S. bovis S1.

In-Vitro Study on Fermentation Characteristics of Different Hulless Barley Cultivar Flakes

Abstract Barley (Hordium vulgare L.) grain is an important food ingredient due to the presence of essential compounds like β-glucans, proteins, resistant starch, phenolic compounds etc. β-glucans are able to lower cholesterol level in blood plasma and the glycaemic index, to enhance lipid metabolism and to reduce the risk of colon cancer. Hulless barley cultivars are more suitable to the human diet, because the hulls can be easily removed, as well as minimal grain processing in food production contributes to the full benefit of the whole grain. Several studies show that hulless grains have a higher digestible energy, and they have higher protein content compared to hulled grains. Different cultivars have unique composition and physical properties. The hulless barley cultivars are less studied than hulled barley and oats. The aim of this study was to evaluate the fermentation characteristics of flakes of different hulless barley cultivars in vitro and to analyse the fermentation pattern of β-glucans and proteins. Samples of six hulless barley cultivar flakes with different β-glucan (4.17–6.59%), soluble dietary fibre (18.1–32.0%) and resistant starch (0.74–10.65%) content were boiled in water 10 min, and the obtained porridge samples were treated under in vitro fementation conditions. The concentration of fermented porridge solids as well as β-glucans and proteins was measured. The concentration of undigested solids varied from 38.3 to 61.0% depending on barley cultivar. The concentration of protein was not significantly changed, but β-glucan concentration was significantly decreased after in vitro digestion comparing to indigestible samples.

Kefir 유래 유산균 Lactobacillus pentosus Strains의 항균 및 항산화 효과

In this study, useful lactic acid bacteria were isolated from kefir, which contains complexes of bacteria, yeast and serves as a reservoir for beneficial strains. As a result of 16s rRNA sequence analysis of 2 strains of kefir-derived lactic acid bacteria with remarkable antimicrobial activity, both BMSE-K006 and K009 showed 99.86% homology with Lactobacillus pentosus DSM 20314. The availability of carbohydrate fermentation patterns of L. pentosus BMSE-K006 and K009 were similar, and the availability of D-galactose and lactose was observed, confirming the availability of sugar in milk or dairy products. Also the antimicrobial activity of L. pentosus BMSE-K006 and K009 showed the highest against pathogenic bacteria such as Staphylococcus spp., Escherichia spp., Pseudomonas aeruginosa, but no antifungal effect was observed against Candida albicans strains. L. pentosus BMSE-K006 and K009 cultured supernatant showed DPPH radical scavenging activity of 69.02% and 65.88%, respectively. Therefore, these results are expected that L. pentosus BMSE-K006 and K009 could be potential resources as useful lactic acid bacteria isolated from kefir.

Leucaena leucocephala leaves and prickly pear (Opuntia ficus-indica) as substitutes for alfalfa hay (Medicago sativa L.) and their effects on the gas and methane production, prevalence of methanogens and patterns of ruminal fermentation in vitro

The aim of the study was to evaluate the replacement of alfalfa hay with Leucaena leucocephala leaves and prickly pear (Opuntia ficus-indica) as an alternative forage, on gas and methane production, ruminal fermentation patterns and total amount of methanogens during in vitro fermentation. Four treatments were evaluated: (T1) alfalfa hay + concentrate (50 : 50%, DM); (T2) alfalfa hay + Leucaena leaves + concentrate (30 : 20 : 50%, DM); (T3) alfalfa hay + prickly pear + concentrate (30 : 20 : 50%, DM) and (T4) alfalfa hay + Leucaena leaves + prickly pear + concentrate (30 : 10 : 10 : 50%, DM). The higher gas production from of soluble fraction (A) and rate gas production (Kd) values, ammonia-N (NH3-N) concentrations and propionate were found in T1 and lower in T2 (p<0.05). Nevertheless, the inclusion of Leucaena leucocephala in the diet decreased the methane production and did not affect the total of methanogens. Results showed that the replacement of alfalfa hay by Leucaena leucocephala and Opuntia ficus-indica in a diet do not affect the main variables of in vitro gas production, ruminal fermentation patterns and methanogenic microorganisms populations.

Effects of dietary supplementation of Mallotus philippensis leaf powder on rumen fermentation pattern, enzyme profile and ciliate protozoal population in growing crossbred calves

The aim of this study was to evaluate the effect of dietary supplementation of Mallotus philippensis (local name 'Kamela') leaf meal on rumen ciliate protozoal population, enzyme profile and fermentation characteristics in growing crossbred calves. Ten growing crossbred (Jersey — Tharparker) calves with an average body weight of 91.8±1.37 kg were divided in to two equal groups (G1 and G2) and fed individually under stall feeding for 140 days on a mixed ration containing paddy straw and concentrate mixture in 50:50 ratio. Two types (C1 and C2) of isonitrogenous concentrate mixtures were prepared. Wheat bran in concentrate mixture (C2) of test group (G2) was partially replaced (4 parts w/w) with sun dried ground Mallotus philippensis leaf meal. Experimental calves of test group (G2) were fed Mallotus philippensis leaf meal @ 2% of the diet. No significant differences were noticed between the two groups for daily dry matter intake while nutrient digestibility, i.e. organic matter and cellulose digestibility were higher in Mallotus philippensis leaf fed calves (G2). However, rumen pH, ammonia nitrogen concentration and total rumen protozoal as well as holotrich and spirotrich protozoal population decreased while ruminal TVFA and propionic acid production increased due to supplementation of Mallotus philippensis leaf. Activities of rumen fibre degrading enzymes e.g. carboxymethyl cellulase, xylanase and β-glucosidase enzyme activities were also higher in Mallotus philippensis leaf meal fed calves (G2). It is concluded that supplementation of Mallotus philippensis leaf have a potential for reducing rumen protozoal population and ammonia nitrogen concentration with improving rumen fibre degrading enzyme activities and nutrient digestibility in growing crossbred calves.

Transcriptome Analysis Reveals Catabolite Control Protein A Regulatory Mechanisms Underlying Glucose-Excess or -Limited Conditions in a Ruminal Bacterium, Streptococcus bovis.

Ruminants may suffer from rumen acidosis when fed with high-concentrate diets due to the higher proliferation and overproduction of lactate by Streptococcus bovis. The catabolite control protein A (CcpA) regulates the transcription of lactate dehydrogenase (ldh) and pyruvate formate-lyase (pfl) in S. bovis, but its role in response to different carbon concentrations remains unclear. To characterize the regulatory mechanisms of CcpA in S. bovis S1 at different levels of carbon, herein, we analyzed the transcriptomic and physiological characteristics of S. bovis S1 and its ccpA mutant strain grown in glucose-excess and glucose-limited conditions. A reduced growth rate and a shift in fermentation pattern from homofermentation to heterofermentation were observed under glucose-limited condition as compared to glucose-excess condition, in S. bovis S1. Additionally, the inactivation of ccpA significantly affected the growth and end metabolites in both conditions. For the glycolytic intermediate, fructose 1,6-bisphosphate (FBP), the concentration significantly reduced at lower glucose conditions; its concentration decreased significantly in the ccpA mutant strain. Transcriptomic results showed that about 46% of the total genes were differentially transcribed between the wild-type strain and ccpA mutant strain grown in glucose-excess conditions; while only 12% genes were differentially transcribed in glucose-limited conditions. Different glucose concentrations led to the differential expression of 38% genes in the wild-type strain, while only half of these were differentially expressed in the ccpA-knockout strain. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses showed that the substrate glucose concentration significantly affected the gene expression in histidine metabolism, nitrogen metabolism, and some carbohydrate metabolism pathways. The deletion of ccpA affected several genes involved in carbohydrate metabolism, such as glycolysis, pyruvate metabolism, fructose and mannose metabolism, as well as in fatty acid biosynthesis pathways in bacteria grown in glucose-excess conditions; this effect was attenuated under glucose-limited conditions. Overall, these findings provide new information on gene transcription and metabolic mechanisms associated with substrate glucose concentration and validate the important role of CcpA in the regulation of carbon metabolism in S. bovis S1 at differential glucose availability.

Can a blend of integrated feed additives modulate ruminal fermentation patterns and performance of growing lambs? In vitro and in vivo assessments

Two in vitro and in vivo experiments were accomplished to investigate the impacts of integrated feed additives (IFA, combination of protected fat, lysine, and methionine plus yucca extract, eucalyptus essential oil, and direct-fed microbial) on gas production (GP), ruminal fermentation and degradability parameters and lamb performance, digestibility, and nitrogen balance. In the in vitro experiment, responses of graded doses (0, 25, 50, 75, 100, and 125 g IFA/kg DM) were evaluated. In the in vivo experiment, 15 Barki male lambs (30.43 ± 0.74 kg BW ± SE) were individually allotted in complete randomized design into three treatments (five animal/treatment) as control (basal diet without additive), low dose (50 g/kg DM) and high dose (100 g/kg DM) for 120 days. In vitro results showed that both doses (100 and 125 g/kg DM) quadratically decreased (p < 0.001) GP and ammonia nitrogen (NH-3N) concentration. In vivo experiment revealed that dry matter intake was increased (p = 0.016) with low dose compared to high dose. Inclusion of high dose decreased blood serum glucose concentrations (p > 0.05) and ruminal protozoal populations (p = 0.094) compared with low dose and control diet. Both doses of IFA increased (p < 0.05) serum urea, creatinine, and triglyceride concentrations, while decreased (p < 0.001) ruminal NH3-N concentrations. These results suggested that, although IFA was effective to modify in vitro ruminal fermentation process and feed degradability, such aspects did not improve in vivo performance of growing lambs.

Biochemical property analysis of native probiotic isolates from selective poultry

Isolation and identification of probiotic bacteria are the prerequisites for their safer use in the food and feed industry. The objectives of the present study were the isolation of probiotic bacteria from the selective gastrointestinal tract of poultry obtained from Khulna and Barisal Divisions, and their identification based on bacterial morphological characterization and biochemical property analysis. Ten potential native probiotics were isolated from the poultry gastrointestinal tract and assayed for their morphological, physiological and biochemical properties. It was observed that, all the isolates were rod-shaped, gram-positive, endospore-negative, catalase-negative, non-motile and were able to ferment particular sugars which are an indicator for typical probiotic bacteria. The sugar fermentation pattern, ability to survive and growth in inhibitory substances like 1-4% NaCl, 0.3% bile salt as well as their ability to grow in different temperatures and pH levels ensured the presumptive identification of the lactic acid bacteria. All the ten isolates exhibited a clear zone of inhibition when they were grown with five enteric pathogens which are indicative of their antimicrobial activity. Ten isolates were assayed for their susceptibility to eight antibiotics using the disc diffusion method. All the isolates were resistant to tetracycline and nalidixic acid. Further research regarding molecular characterization and identification of specific genes using different technologies may open the door to utilize these isolates in different probiotic-based inventions. Bang. J. Livs. Res. Vol. 27 (1&amp;2), 2020: P. 39-54

The potential of nitrate supplementation for modulating the fermentation pattern and mitigating methane emission in ruminants: A meta-analysis from in vitro experiments

The aim of this study was to evaluate the potential of nitrate supplementation as an in vitro feed additive for modulating the rumen fermentation pattern and mitigating the enteric methane emission by using a meta-analysis method. A database was built from the previously published articles regarding the effectiveness of nitrate as a feed additive in the in vitro rumen fermentation system. Different doses or forms of nitrate supplementations were identified in the database. A total of thirteen studies containing 47 data sets were obtained from ten published research papers. The obtained data were subjected to the mixed model methodology. The doses or the different forms of nitrate were treated as a fixed factor, while the different studies were considered as a random effect. Results showed that nitrate addition decreased significantly (P<0.05) the total gas production, methane production, the TVFAs, and the acetic acid, and increased significantly (P<0.05) ammonia concentration in a linear pattern. However, nitrate did not affect significantly the rumen pH and the population of methanogenic archaea. In conclusion, nitrate is an effective additive for modulating the rumen fermentation by altering the fermentation process resulting in a lower methane production.

Silage fermentation characteristics and microbial diversity of alfalfa (Medicago sativa L.) in response to exogenous microbiota from temperate grasses.

The objective of this study was to explore the microbiological factors that cause the difference in silage fermentation characteristics between grass and legume. Specifically, the effects of epiphytic microbiota from alfalfa, oat and Italian ryegrass on ensiling characteristics and microbial community of alfalfa were assessed. By γ-ray irradiation sterilization and microbiota transplantation technology, the sterile alfalfa was inoculated as follows: (i) aseptic water (STAL); (ii) epiphytic bacteria from alfalfa (ALAL); (iii) epiphytic bacteria from oat (ALOT); (iv) epiphytic bacteria from Italian ryegrass (ALIR). Alfalfa at the initial flowering stage was ensiled in laboratory-scale silos for 1, 3, 7, 14, 30 and 60 days. Compared with ALAL and ALIR, higher lactic acid contents and ratio of lactic acid to acetic acid, and lower acetic acid, propionic acid, ethanol and ammonia nitrogen contents were observed in ALOT after 60 days of fermentation. In each treated group, Lactobacillus was the most dominant genus after 60 days of ensiling. Relatively higher abundance of Weissella, Hafnia-Obesumbacterium, Enterobacteriaceae or hetero-fermentative Lactobacillus was found in ALAL and ALIR after 60 days. Co-occurrence network analysis proved Pediococcus and Lactococcus were pivotal in deciding the fermentation pattern of alfalfa silage. According to the 16S rRNA gene-predicted functional profiles, the metabolism of amino acids was inhibited by the epiphytic microbiota from oat. Overall, ALOT showed a homo-fermentative process, whereas ALAL and ALIR exhibited a hetero-fermentative pattern. Furthermore, the exogenous microorganisms inhibiting the metabolism of amino acids can be a good potential source to improve the silage quality of legume forage.

Fermentation profile and microbial diversity of temperate grass silage inoculated with epiphytic microbiota from tropical grasses.

This study was designed to evaluate the effects of epiphytic microbiota from Italian ryegrass (IRIR), Napier grass (IRNP) and Sudan grass (IRSD) on ensiling characteristics and microbial community of Italian ryegrass silage. Each treatment was prepared in triplicate and ensiled in plastic bag silos for 1, 3, 7, 14, 30 and 60days. The γ-ray irradiation sterilization method, microbiota transplantation and next generation sequencing technology were used. Results indicated that significantly (P < 0.05) higher ratio of lactic acid to acetic acid, and lower acetic acid and ammonia nitrogen contents were observed in IRNP than IRIR and IRSD after 60days of ensiling. Lactobacillus was the most predominant in each treatment at the late stage of fermentation. Lactococcus was eventually replaced by Lactobacillus in IRSD, whereas higher abundance of Lactococcus was continuously found in IRNP. Co-occurrence network analysis demonstrated Lactococcus was pivotal in determining the silage fermentation pattern of Italian ryegrass. According to the 16S rRNA gene-predicted functional profiles, the metabolism of amino acids was enhanced by the epiphytic microbiota from Italian ryegrass and Sudan grass, while the carbohydrate metabolism was accelerated by the epiphytic microbiota from Napier grass. Overall, IRNP had a homo-fermentative process, whereas IRIR and IRSD possessed a hetero-fermentative pattern. The Lactococcus and heterofermentative Lactobacillus were mainly responsible for this. It also confirmed that the exogenous microorganisms that promote the carbohydrate metabolism and inhibit the metabolism of amino acids could be a good potential source to improve the silage quality of temperate grass.

Modified Nano-Montmorillonite and Monensin Modulate In Vitro Ruminal Fermentation, Nutrient Degradability, and Methanogenesis Differently.

Simple SummaryNatural montmorillonite (NM) is the most common clay used as a feed additive in ruminant diets. Under normal pH conditions, it can adsorb hydrogen and may affect methane (CH4) formation; however, it possesses less efficiency than other clays. Due to NM’s negative charge flat surface and positive charge edges, its physicochemical properties can be modified by cationic or anionic surfactants. Therefore, two types of modified nano-montmorillonite (MNM) were developed by ion-exchange reactions using cationic and anionic surfactants. Comparisons were made with monensin as a rumen modulator to reduce CH4 emission from ruminants. The results indicated that the physicochemical properties of both MNM types were enhanced (e.g., cation-exchange capacity and zeta potential). All MNM clays and monensin successfully reduced rumen CH4 production and ammonia concentration; however, clay modified by cationic surfactant was more efficient than what was modified by anionic surfactant in modulating in vitro rumen fermentation propertiesTwo types of modified nano-montmorillonite (MNM) were developed by ion-exchange reactions using two different surfactants; sodium dodecyl sulfate (SDS) and cetyltrimethylammonium bromide (CETAB), to prepare MNMSDS and MNMCETAB, respectively. Both MNM types were on the nano-scale and had higher cation-exchange capacity values than NM clay. The MNMCETAB had the highest zeta potential (−27 mV) compared with the other clays. Effects of MNM types on in vitro ruminal batch culture fermentation, nutrient degradability, and methane (CH4) emission compared with monensin were evaluated in vitro using a semi-automatic gas production system. The experimental treatments were the control (0 supplementations), monensin (40 mg/kg DM), and NM (5 g NM/kg DM), and two levels of MNMSDS and MNMCETAB were supplemented at 0.05 (low) and 0.5 (high) g/kg DM to the control basal feed substrate. Among the experimental treatments, the high dose of both MNM types reduced (p < 0.01) CH4 production and ammonia concentrations compared with the control, while only MNMCETAB treatment tended to increase (p = 0.08) the truly degraded organic matter compared with monensin. All MNM treatments increased (p < 0.01) acetate molar proportions compared with monensin. The high MNMCETAB increased (p < 0.01) the in vitro ruminal batch culture pH compared with the control and monensin. The MNMCETAB supplemented at 0.5 g/kg DM is the most efficient additive to reduce CH4 emission with the advantage of enhancing the in vitro nutrient degradability of the experimental feed substrate. These results indicated that MNM could modulate the in vitro ruminal fermentation pattern in a dose- and type-dependent manner.

Intercropped maize‐soybean silage: Effects on forage yield, fermentation pattern and nutritional composition

AbstractWe investigated whether the intercropping of maize and soybean could improve the silage nutritional content without reducing the forage yield or worsening silage fermentation process and aerobic stability. Three crop arrangements were studied: maize monoculture, soybean monoculture and maize‐soybean intercropping. The experimental design was completely randomized with 5 replicates per treatment. Maize‐soybean intercropping decreased the dry matter (DM) and grain yield as well as the production of digestible dry matter per hectare. The crude protein content of maize‐soybean intercropped silage was higher compared with maize in monoculture (by 40%), but, on average, both silages presented similar fermentation profile, in vitro digestibility (600 g/kg DM), dry matter loss (37.1 g/kg DM), gas loss (36 g/kg DM) and aerobic stability (60 hr). Soybean‐crop silage presented an elevated content of volatile organic compounds, low lactic acid concentration (2 g/kg DM), high pH (5.26), and greater losses of dry matter (73 g/kg DM) and gas (98.5 g/kg DM) during fermentation. Aerobic stability was higher in soybean‐crop silage (192 hr) due to the high content of volatile fatty acids (butyric acid &gt; 87 g/kg DM) and low contents of residual sugar and lactic acid. In conclusion, maize and soybean intercropping increased crude protein content, but contrary to our hypothesis, the crop association did not result in greater silage digestibility or higher aerobic stability, nonetheless reduced both crop productivity. Additionally, ensiling direct‐cut soybean crop with low DM content is not recommended due to the high risk of undesirable fermentation and nutrient losses.

288 Inclusion Effects of Quebracho (Schinopsis Balansaie) Extract and Active Dry Yeast (Saccharomyces Cerevisiae) in Beef Cattle Limit-fed a Grower Ration

Abstract Plant secondary metabolites (PSM) and yeast supplemented in growing cattle have been reported as improving dry matter digestibility (DMD) and reducing enteric methane emissions. This study aimed to evaluate the effect of combined supplementation with condensed tannin (CT; Schinopsis balansae) extract and active dry yeast (ADY; Saccharomyces cerevisiae) on fermentation dynamics, utilizing in vitro gas production (IVGP) technique. A 2 × 2 Latin square design was used to study fermentation patterns of four dietary treatments (CON- no CT and no ADY, ADY alone, CT alone or combined CT + ADY). Animals received daily CT at 1% DM and 10 g of ADY, respectively. On d 0, 7, 14, 21, 28, and 35 rumen inoculum was collected from 23 fistulated steers (284.3 ± 4.1 kg) four hours post-feeding. Samples were incubated under anaerobic conditions at 39oC for 48 h with 200 mg of a grower diet (14.8% CP, 40.6% NDF, 88.5% DM). Gas parameters were analyzed using a mixed linear statistical model. There was a day effect for total gas production (TGP; P &amp;lt; 0.001), non-fiber carbohydrate degradation (P = 0.031) and fractional degradation assuming an asymptote model (P = 0.015). Both asymptote and non-fiber fractional degradation rate estimates had an interaction between Day × TRT (P = 0.001 and 0.0104, respectively). Data were analyzed using polynomial contrasts showed a difference in non-fiber fractional rate of fermentation for CON × CT and CT × ADY (P = 0.052 and 0.054, respectively). This was also true if an asymptote model was assumed (P = 0.0 34 and 0.034, respectively). We concluded that combined supplementation of CT and ADY exhibited similar IVGP trends over time, this may be because animals only received a grower diet at 1.5% shrunk BW. Future studies should investigate the impact of combined supplementation on varying levels of concentrate diets.

Effect of Alfalfa Hay Substitution by Raw Garlic Leaves on In vitro Gas Methane Production and Ruminal Fermentation

Background: The aim of present research was to evaluate under in vitro conditions, the effect of alfalfa hay substitution by raw garlic leaves on ruminal fermentation patterns and methane production in diets ruminants. Methods: Four treatments were evaluated: (T1) alfalfa hay (50%); (T2) alfalfa hay (33%) + raw garlic leaves (17%); (T3) alfalfa hay (17%) + raw garlic leaves (33%) and (T4) raw garlic leaves (50%). Result: The highest values of fractional rate of gas production (kd), ammonia-nitrogen (NH3-N), propionate and microbial biomass synthesis (MBS) was recorded in T4 and the lowest in T1 (P less than 0.05). In contrast, the highest methane production was recorded in T1 and the lowest in T4 (P less than 0.05). It was concluded that the substitution of alfalfa hay by raw garlic leaves in diet with 50% roughages and 50% concentrate result in an improvement in vitro rumen fermentation pattern and decreases the methane production.

Rumen-protected glucose supplementation in transition dairy cows shifts fermentation patterns and enhances mucosal immunity.

Manipulation of perinatal diets, such as supplementing feed with rumen-protected glucose (RPG), has been positively regarded as a strategy to improve milking performance. This study was conducted to assess the effects of RPG on the fermentation profiles, resident microbiota and mucosal immunity in the cecum. Ten Holstein dairy cows were randomly assigned to either a 25 g/kg RPG diet (DM basis) or a 11 g/kg coating fat diet (control, CON). Compared with the CON group, the acetate-to-propionate ratio was lower in the RPG group. Gene expression analysis indicated that RPG supplementation tended to upregulate the expression of Na+/H+ hydrogen exchanger 3 (NHE3) (P = 0.076). RPG supplementation downregulated the expression of genes involved in self-rehabilitation such as matrix metalloproteinase 1 (MMP1), MMP3, MMP9 and MMP13. Additionally, the mRNA expression of genes involved in immunity including Toll-like receptors (TLR4, TLR6 and TLR7) and proinflammatory cytokines (immune interferon gamma [IFNG] and interleukins interleukin 17A [IL17F], IL17A, IL22), was downregulated by RPG supplementation. Nonetheless, no differences existed in the bacterial copy number and beta diversity between the 2 groups. Overall, supplementation with RPG would probably cause a shift towards propionate production in the cecal digesta, and promote the immune homeostasis of the cecal mucosa in transition dairy cows. Our results extended the basic understanding of RPG supplementation and utilization in transition dairy cows in terms of host microbe interplay in the cecum.