Proportion Of Butyrate Research Articles

Содержание короткоцепочечных жирных кислот в кале и потенциальные возможности коррекции кишечной микробиоты у пациентов с синдромом раздраженного кишечника с различной массой тела

Aim: to evaluate the fecal content of short-chain fatty acids (SCFAs) in patients with irritable bowel syndrome (IBS) across different body weight categories and to formulate recommendations for the personalized patient management with IBS. Patients and Methods: an open cross-sectional study was conducted with 175 patients aged 18 to 44 years. Participants were divided into the following groups: group 1: 100 patients diagnosed with IBS, further divided into: subgroup 1A: 50 overweight or obese patients; subgroup 1B: 50 patients with normal weight; group 2: 75 patients without IBS, further divided into: subgroup 2A: 50 overweight or obese patients; subgroup 2B: 25 conditionally healthy patients with normal weight. The severity and presence of IBS symptoms were evaluated using a 10-point scale. Parameters studied included eating habits, quality of life, and specific anxiety, assessed through validated questionnaires. Absolute and relative concentrations of SCFAs and zonulin in fecal samples were measured. Additionally, serum concentrations of leptin and adiponectin were assessed. Results: overweight and obese individuals exhibited a higher fecal SCFA content, independent of IBS presence. Within the IBS cohort, distinct SCFA profiles were noted based on IBS subtype. IBS with diarrhea predominance (IBS-D) was characterized by the highest absolute concentrations of acetate, propionate, and butyrate, increased relative proportions of propionate and butyrate, a significant shift in the anaerobic index into a markedly negative range. IBS with constipation predominance (IBS-C) showed the lowest absolute concentrations of acetate, propionate, and butyrate, elevated relative levels of acetate and isoacids and a milder shift in the anaerobic index toward a slightly negative range. SCFA levels were associated with IBS symptom severity, dietary patterns, intestinal epithelial barrier permeability, and concentrations of adipose tissue-related hormones such as leptin and adiponectin. Conclusion: the results suggest a potential role of the gut microbiota and its metabolites in shaping the clinical phenotype of IBS, particularly in overweight and obese patients. These results highlight the need for further research into personalized treatment approaches for IBS based on SCFA profiles and microbiota-associated mechanisms. Future studies may allow for the optimization of existing IBS treatment tactics, incorporating targeted dietary, lifestyle, and therapeutic modifications tailored to individual microbiota patterns. Keywords: irritable bowel syndrome, short-chain fatty acids, acetate, propionate, butyrate, obesity. For citation: Fedorin M.M., Livzan M.A., Gaus O.V., Druk I.V. Content of short-chain fatty acids in feces and the potential for correction of the intestinal microbiota in patients with irritable bowel syndrome with different body weight. RMJ. 2024;10:2–8. DOI: 10.32364/2225- 2282-2024-10-1

Enzyme production mechanism of anaerobic fungus Orpinomyces sp. YF3 in yak rumen induced by different carbon source

In order to investigate the enzyme production mechanism of yak rumen-derived anaerobic fungus Orpinomyces sp. YF3 under the induction of different carbon sources, anaerobic culture tubes were used for in vitro fermentation. 8 g/L of glucose (Glu), filter paper (Flp) and avicel (Avi) were respectively added to 10 mL of basic culture medium as the sole carbon source. The activity of fiber-degrading enzyme and the concentration of volatile fatty acid in the fermentation liquid were detected, and the enzyme producing mechanism of Orpinomyces sp. YF3 was explored by transcriptomics. It was found that, in glucose-induced fermentation solution, the activities of carboxymethyl cellulase, microcrystalline cellulase, filter paper enzyme, xylanase and the proportion of acetate were significantly increased (P < 0.05), the proportion of propionate, butyrate, isobutyrate were significantly decreased (P < 0.05). The results of transcriptome analysis showed that there were 5 949 differentially expressed genes (DEGs) between the Glu group and the Flp group, 10 970 DEGs between the Glu group and the Avi group, and 6 057 DEGs between the Flp group and the Avi group. It was found that the DEGs associated with fiber degrading enzymes were significantly up-regulated in the Glu group. Gene ontology (GO) function enrichment analysis identified that DEGs were mainly associated with the xylan catabolic process, hemicellulose metabolic process, β-glucan metabolic process, cellulase activity, endo-1,4-β-xylanase activity, cell wall polysaccharide metabolic process, carbohydrate catabolic process, glucan catabolic process and carbohydrate metabolic process. Moreover, the differentially expressed pathways associated with fiber degrading enzymes enriched by Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis were mainly starch and sucrose metabolic pathways and other glycan degradation pathways. In conclusion, Orpinomyces sp. YF3 with glucose as carbon source substrate significantly increased the activity of cellulose degrading enzyme and the proportion of acetate, decreased the proportion of propionate, butyrate and isobutyrate. Furthermore, the degradation ability and energy utilization efficiency of fungus in the presence of glucose were improved by means of regulating the expression of cellulose degrading enzyme gene and participating in starch and sucrose metabolism pathway, and other glycan degradation pathways, which provides a theoretical basis for the application of Orpinomyces sp. YF3 in practical production and facilitates the application of Orpinomyces sp. YF3 in the future.

The Effects of Grass Silage Additive Type and Barley Grain Preservation Method on Rumen Function, Microbial Ecology, and Energy Metabolism of Dairy Cows

The effects of grass silage and barley grain preservation methods on dairy cows were evaluated using four Nordic Red dairy cows placed in respiration chambers in a 4 × 4 Latin square. Silage was conserved using a formic acid-based product (AS) or a homofermentative lactic acid bacteria inoculant (IS), while grains were dried (DB) or crimped and ensiled (EB). Fermentation profile of silages and the chemical composition of the mixed diets were very similar. The dietary treatments did not affect feed intake, milk production, and rumen fermentation except molar proportion of butyrate, and energy metabolism. Digestibility of dry matter and organic matter were higher (p &lt; 0.05) and that of crude protein was lower (p &lt; 0.05) for AS than IS. Feeding EB compared to DB decreased (p &lt; 0.05) diet organic matter and starch digestibility. The cows receiving AS tended (p = 0.06) to emit more methane per day than those receiving IS, but methane yield and intensity were not different between dietary treatments. Bacteria alpha diversity was higher (p &lt; 0.01) in barley samples than grass silages and was not affected by the diet in rumen samples. All freshly prepared rations were dominated by Lactobacillaceae, Erwiniaceae, and Pseudomonadaceae but rations based on AS than IS remained more stable over 2 days. In conclusion, grass silage and barley grain preservation methods did not affect the measured parameters in dairy cows and the preservation method can be selected based on practical on-farm factors.

PSI-6 Effects of a Postbiotic Program Consisting of Liquid and Solid Saccharomyces Cerevisiae Fermentation Products on Digestibility, Ruminal Fermentation, and Plasma Metabolome of Finishing Beef Steers

Abstract The objective of this study was to determine the effects of a postbiotic feeding program consisting of liquid and solid Saccharomyces cerevisiae fermentation products (SCFP) on digestibility, ruminal fermentation, and plasma metabolome of finishing beef steers. Eight Holstein steers (BW 467 ± 13.9 kg) equipped with rumen cannulas were used in a crossover design study, with 21-d per period and 7-d washout period in between periods. Steers were blocked based on initial BW to one of two treatments: 1) Control, basal diet only (CON), or 2) SCFP, one day feeding of LiquiCare RTU (Diamond V, dosed via rumen cannula at 11 mL/100 kg BW) followed by daily feeding of 12 g NaturSafe (Diamond V, top-dressed). Feed and fecal samples were collected during d 17 to 20 for determination of digestibility and fecal excretion of N, P, Cu and Zn using acid-insoluble ash as an internal marker. Blood samples were collected on d 21 before morning feeding. Rumen fluid samples were collected on d 0, 1, 2, 3, 5 and 21 at 0, 4, 8, or 12 h post morning feeding via rumen cannula. Results were analyzed with the GLIMMIX procedure of SAS 9.4 (SAS, 2022). BW, DMI and digestibility were not affected by treatment. There was a tendency of treatment by period interaction (P = 0.09) on feed efficiency, which was improved by feeding SCFP only in period 1. Feeding SCFP did not affect (P &amp;gt; 0.10) ruminal pH. Feeding SCFP tended to reduce ruminal lactate concentration on d 21 (0.09 vs. 0.02 mM, P = 0.10). Supplementing SCFP reduced ruminal NH3-N concentration on d 2 (4.24 vs. 7.31 mg/dL, P = 0.03) and d 21 (4.86 vs. 6.83 mg/dL, P = 0.04). By feeding SCFP, ruminal total VFA concentration was increased 4-h post-feeding on d 5 (139.7 vs. 126.7 mM, P = 0.01) and numerically increased 4-h post-feeding on d 21 (151.2 vs. 133.3 mM, P = 0.12). For VFA composition, no treatment differences were observed on day 21. However, feeding SCFP reduced (P = 0.01) propionate proportion and increased (P = 0.05) butyrate proportion on day 3. The enriched plasma metabolic pathways (P ≤ 0.05) by feeding SCFP are citric acid cycle, pyrimidine metabolism, glycolysis/gluconeogenesis, retinol metabolism, and inositol phosphate metabolism pathways. Overall, our results indicated potential benefits of the SCFP feeding program on improving ruminal fermentation, preventing acidosis and improving N utilization in the rumen. Furthermore, feeding SCFP enriched several important pathways in lipid, protein, and glucose metabolism, which may improve feed efficiency of energy and protein in finishing beef cattle.

224 Effects of Feeding Hybrid Rye Grain as a Replacement for Barley Grain on Feed Intake, Ruminal Fermentation, and Site of Nutrient Digestion for Finishing Beef Cattle

Abstract The objective of this study was to evaluate effects of increasing hybrid rye as a replacement for barley grain on feed intake, ruminal fermentation, and site of nutrient digestion in finishing cattle. Eight ruminally and duodenally cannulated Hereford-cross heifers (starting body weight = 514 ± 25.3 kg) were used in a replicated 4×4 Latin square design with 21-d periods including 15 d of dietary adaptation and 6 d of sample collection. Dietary treatments included a control diet with 10.0% hay, 85.2% barley grain, and 4.8% of a vitamin and mineral supplement on a dry matter (DM) basis. Hybrid rye grain replaced 33, 67, or 100% of the barley grain. Both cereal grains were dry rolled to 80% processing index. Feed, refusals, ruminal fluid, duodenal digesta, and fecal samples were collected. Data were analyzed using the MIXED procedure of SAS 9.4 (SAS Inst. Inc., Cary, NC). Increasing hybrid rye inclusion tended (P = 0.052) to linearly decrease DM intake. Additionally, increasing hybrid rye grain linearly decreased mean and minimum ruminal pH (P &amp;lt; 0.01) and increased the duration (P &amp;lt; 0.01) and area (P = 0.01) that pH was less than 5.5. There was no effect of hybrid rye inclusion on total short chain fatty acid, lactic acid concentrations, or osmolality. Likewise, the molar proportion of acetate and butyrate were not affected by hybrid rye inclusion. Propionate tended to linearly increase with increasing hybrid rye inclusion (P = 0.08). Increasing hybrid rye linearly increased NH3-N concentration (P = 0.03). Ruminal organic matter (OM) digestibility tended to linearly increase (P = 0.08) and ash-free neutral detergent fiber (aNDFom) digestibility linearly increased (P &amp;lt; 0.01) when increasing hybrid rye. There was no effect on ruminal starch digestibility (71.1 ± 5.12%). Intestinal digestibility of CP linearly decreased (P = 0.050), but there were no effects for other nutrients. Increasing hybrid rye linearly increased apparent total-tract DM, OM, and aNDFom digestibility (P &amp;lt; 0.05) but did not affect starch digestibility (97.4 ± 0.42%). Increasing the inclusion rate of hybrid rye grain at the expense of barley grain in finishing diets may decrease DMI and increase risk for ruminal acidosis; however, hybrid rye inclusion did not influence the site or extent of starch digestion and increased total tract digestibility of DM, OM, and aNDFom.

PSI-24 Trace Mineral Source, Diet Type, and Rumensin Influences Ruminal Fermentation Characteristics

Abstract Sixteen Angus crossbred steers (531 ± 22.7 kg), fitted with rumen canulae, were used to determine the impact of trace mineral (TM) source, diet type, and Rumensin (R) or Rumensin + Tyolsin (RT) supplementation on rumen fermentation characteristics. In experiment 1, steers were individually housed and fed a high concentrate finishing diet for 21 d. Steers were then blocked (n = 4 steers/block) based on mean dry matter intake (DMI) over the acclamation period. Steer blocks were then randomly assigned to 4 dietary treatments for 28 d. A 2 x 2 factorial arrangement of treatments was used. Factors included: 1) TM source (Sulfate or Hydroxy Cu, Mn, and Zn TM supplemented at 18, 40, and 90, mg/kg DM, respectively), and 2) with or without RT (supplemented at 36.3 and 11 g/metric ton DM, respectively). Following the 28-d feeding period, rumen samples were collected at 0, 2, and 4 h post-feeding. On experiment 2, all steers were then transitioned to a lactating dairy diet for 21 d. Steers were then blocked and assigned to treatments for 28 d. Treatments included: 1) TM source (Sulfate or Hydroxy Cu, Mn, and Zn TM supplemented at 10, 50, and 60, mg/kg DM, respectively) and 2) with or without R (0.0 or 24.2 g of R/metric ton DM). Following the 28-d feeding period, rumen samples were collected as described previously. Rumen fluid samples from both experiments were analyzed for short chain fatty acids (SCFA), pH, and ammonia concentrations. Within an experiment, data over the three time periods (0, 2, and 4 h) were averaged for each parameter measured before statistical analysis. In experiment 1, Molar proportions of acetate were lesser (P &amp;lt; 0.04) and propionate greater (P &amp;lt; 0.01) in steers receiving Hydroxy TM compared with steers receiving Sulfate TM. All other rumen fermentation characteristics measured in this experiment were similar across TM source. Rumen molar concentrations of acetic acid were less in steers receiving RT than steers not receiving RT. Steers receiving RT and Hydroxy TM tended (P &amp;lt; 0.10) to have decreased rumen ammonia concentrations compared with steers receiving RT and Sulfate TM. In experiment 2, there were no TM source impacts on the rumen fermentation characteristics measured. Supplementation of R reduced molar concentrations (P &amp;lt; 0.02) and proportions (P &amp;lt; 0.01) of acetate and increased molar concentrations and proportions of propionate (P &amp;lt; 0.01, P &amp;lt; 0.01, respectively) and butyrate (P &amp;lt; 0.02, P &amp;lt; 0.04, respectively). These data indicate that TM source, R, and RT may modulate rumen fermentation characteristics but their impacts on rumen fermentation may be diet dependent.

37 Effects of Creep Feeding Duration on Rumen Fermentation Characteristics Using an Ex Vivo Model

Abstract The objective was to determine the effects of creep feeding duration on ruminal fermentation using an ex vivo model. Simmental × Angus, spring-born calves (n = 72) were stratified by age (83 ± 14 d) and body weight (BW) into 12 pens with 6 calves per pen. Pens were randomly assigned to 1 of 2 treatments: calves fed creep for 105 d (105dCF) or final 21 d (21dCF) before weaning. Cow-calf pairs were housed on concrete drylots with open-front buildings. Cows were limit-fed at maintenance a total mixed ration (TMR) that consisted of corn, grain coproducts, and corn stalks. Calves (n = 16) were utilized for ex vivo experiments. Experiment 1 was conducted on d 76, before the 21dCF calves having access to creep feed. Rumen fluid was collected from 8 calves per treatment via esophageal tubing and mixed with McDougall’s buffer (1:2 ratio). Each rumen fluid inoculum was combined with 2 substrates (cow TMR or creep feed) in a split-plot design and incubated for 24 h at 39°C. Data were analyzed using the MIXED procedure of SAS 9.4. In Exp. 1, there was no creep feeding duration by substrate interaction (P ≥ 0.16) for 24-h pH, butyrate, acetate, or IVDMD. Molar proportions of acetate and butyrate were greater (P ≤ 0.001) for the 105dCF calves than for the 21dCF calves. There was a treatment by substrate interaction (P = 0.02) for total VFA. The 105dCF calves had greater total VFA than 21dCF calves with a greater magnitude of difference observed with TMR substrate. Calves on 105dCF had greater (P &amp;lt; 0.01) IVDMD than 21dCF calves regardless of substrate (64% and 59%, respectively). Experiment 2 was conducted on day 105 after all calves were abruptly weaned and transported 263 km to the feedlot. Procedures were similar to Exp. 1, except substrates included creep feed and feedlot receiving diet. In Exp. 2, no treatment by substrate interaction (P ≥ 0.13) was observed for 24-h pH, acetate, propionate, total VFA, or IVDMD. Although acetate was greater (P &amp;lt; 0.01) for the 105dCF calves, propionate was greater (P &amp;lt; 0.01) for the 21dCF calves. There was no treatment effect (P = 0.57) for total VFA; however, it was greater (P &amp;lt; 0.01) for the creep feed substrate than for the receiving diet substrate. In Exp. 2, IVDMD tended to be greater (P = 0.06) for 21dCF calves than 105dCF calves. In conclusion, results indicated creep feeding improved ruminal fermentation ex vivo, but even a short-term creep feeding duration of 21 d appears to be adequate in preparing rumen microbial community to degrade the receiving diet as there were fewer differences in rumen fermentation characteristics at feedlot arrival.

Effect of structural characteristics of resistant starch prepared by various methods on microbial community and fermentative products

Resistant starch (RS) has been extensively studied because of its beneficial effects on gut microbiota. In this study, four RSs obtained through various preparation processes were utilized for in vitro fermentation, and their structural characteristics before and after fermentation were determined using chromatography, Fourier infrared spectroscopy, and scanning electron microscopy (SEM). It was observed that these RSs can be classified into two categories based on their fermentation and structural features. The autoclaving RS (ARS) and extruding RS (ERS) were classified as Class I Microbiome Community (MC-I), characterized by a higher proportion of butyrate and its producers, including unclassified_g_Megasphaera and Megasphaera elsdenii. While microwaving RS (MRS) and ultrasound RS (URS) belonged to Class II Microbiome Community (MC-II), marked by a higher proportion of acetate and its producer, Bifidobacterium pseudocatenulatum DSM 20438. MC-I had a lower molecular weight, shorter chain length, more chains with degree of polymerization (DP) 36–100, and a more ordered structure than MC-II. Furthermore, SEM observations revealed distinct degradation patterns between MC-I and MC-II, which may be attributed to their surface structural characteristics. These findings imply that the preparation methods employed for RS can determine its multilevel structural characteristics, and consequently influence its physiological properties.

211 Evaluating the Influence of Soybean Meal and its Bioactive Compounds on Nutrient Utilization, Fermentation, and Gastrointestinal Metabolites of Nursery Pigs

Abstract Recently soybean meal (SBM) has garnered more attention due to its increased feeding value during periods of stress and improved bioavailable energy. However, the influence of the innate bioactive compounds in SBM on the microbiome and fermentation products have not been fully elucidated. Thus, the experimental objective was to investigate the mechanism of action of SBM and its bioactive compounds in the gastrointestinal tract of nursery pigs. Two replications of 18 barrows (8.12 ± 0.80 kg BW; PIC800 × Camborough; n = 36), were randomly assigned to a dietary treatment of either a high SBM positive control (SBMC; 28.6%), a negative control void of SBM (SP), but included soy protein isolate and concentrate to provide amino acids from soy protein the same as SBM in SBMC; SP formulated to the same contribution and composition of isoflavones as SBMC (SP+ISO; 528 mg/kg of soy-isoflavones); SP diet fortified with soybean functional lipids of lecithin and phytosterols at similar concentration in SBMC (SP+LIP; 2.85 g/kg of functional lipids); SP formulated to the same contribution and ratio of insoluble to soluble fiber as SBM in SBMC (SP+FIB; 30 g/kg of soy fiber); or SP diet fortified with lunasin peptide at 3.81 g/kg (SP+LUN). Pigs were individually housed, and limit fed 2.5 times maintenance for a metabolism study consisting of a 6-d adaptation period, followed by 72-h of urine and fecal collections. On d 12, pigs were necropsied, and ileal, cecal, and colonic digesta were collected for immediate short-chain fatty acid (SCFA) analysis. The pH of ileal and cecal digesta were also collected. Data were analyzed as a linear mixed model with treatment as a fixed effect, replicate as a random effect, and initial BW as a covariate where appropriate using PROC MIXED in SAS 9.4. The pH of both ileal (P = 0.478) and cecal (P = 0.874) digesta did not differ among treatments. Relative to SP, pigs fed SP+FIB and SBM had a 97.8% and 63.4% increase in acetate production, respectively (P = 0.012). Similarly, pigs fed SP+FIB and SBM had increased total SCFA concentration in the ileum (P = 0.016), but there was no difference among treatments for propionate or butyrate production (P &amp;gt; 0.05). The molar proportion of butyrate was increased in the cecum in pigs fed SBMC and SP+FIB (P &amp;lt; 0.01), which increased the total concentration (mM/g) of SCFA in the cecal digesta (P &amp;lt; 0.05). The SP+FIB treatment had increased concentration (mM/g) and molar proportion of butyrate produced in the colon (P &amp;lt; 0.01). While pigs fed SBMC and SP had increased molar proportion of propionate in the colon (P &amp;lt; 0.05), total colonic SCFA concentration did not differ (P &amp;gt; 0.05). Collectively, SBM and its fiber can modulate SCFA composition and production in nursery pigs, and this may be related to an increase in fermentable substrates available to the microbiome.

Feeding alfalfa-grass or red clover–grass mixture baleage: Effect on milk yield and composition, ruminal fermentation and microbiota taxa relative abundance, and nutrient utilization in dairy cows

Our goal was to investigate the effect of diets containing baleages harvested from alfalfa-grass or red clover-grass mixture on production performance, ruminal fermentation and microbiota taxa relative abundance, milk fatty acid profile, and nutrient utilization in dairy cows. Twenty Jersey cows (18 multiparous and 2 primiparous) averaging (mean ± SD) 148 ± 45.2 days in milk and 483 ± 65.4 kg of body weight in the beginning of the study were used in a randomized complete block design with repeated measures over time. The experiment lasted 9 wk, with a 2 wk covariate period followed by 7 wk of data and sample collection (wk 4 and 7 used in the statistical analyses). Cows were fed diets containing (dry matter basis) 35% of a concentrate mash and the following forage sources: (1) 65% second- and third-cut (32.5% each) alfalfa-grass mixture baleages (ALF) or (2) 65% second- and third-cut (32.5% each) red clover-grass mixture baleages (RC). Diets did not affect dry matter intake, milk yield, and concentrations of milk fat and true protein. In contrast, milk fat yield tended to decrease and energy-corrected milk yield decreased with feeding RC versus ALF. The apparent total-tract digestibilities of dry matter, organic matter, and ash-free neutral detergent fiber, milk proportions of trans-10 18:1, cis-9,cis-12,cis-15 18:3, and total n-3 fatty acids, ruminal molar proportion of acetate, and plasma concentrations of Leu, Phe, and Val all increased in RC versus ALF. Diet × week interactions were found for several parameters, most notably ruminal molar proportions of propionate and butyrate, ruminal NH3-N, milk urea N, plasma urea N, and plasma His concentrations, urinary N excretion, enteric CH4 production, and all energy efficiency variables. Specifically, ruminal NH3-N and plasma urea N concentrations, urinary excretion of N, and CH4 production decreased in cows fed RC in wk 4 but not in wk 7. Milk urea N concentration decreased and that of plasma His increased with feeding RC during wk 4 and 7, although the magnitude of treatments difference varied between the sampling periods. Efficiency of energy utilization calculated as milk energy/metabolizable energy decreased and that of tissue energy/ME increased in RC versus ALF cows in wk 4, suggesting that ME was portioned toward tissue and not milk in the RC diet. Interactions were also observed for the relative abundance of the rumen bacterial phyla Verrucomicrobiota and Fibrobacterota, with cows offered RC showing greater values than those receiving ALF in wk 4 but no differences in wk 7. Several diet × week interactions were detected in the present study implying short-term treatment responses and warranting further investigations.

Gas exchange, rumen hydrogen sinks, and nutrient digestibility and metabolism in lactating dairy cows fed 3-nitrooxypropanol and cracked rapeseed

Fat in the form of cracked rapeseed and 3-nitrooxypropanol (3-NOP, market as Bovaer) were fed alone or in combination to 4 Danish Holstein multicannulated dairy cows, with the objective to investigate effects on gas exchange, dry matter intake (DMI), nutrient digestion, and nutrient metabolism. The study design was a 4 × 4 Latin square with a 2 × 2 factorial treatment arrangement with 2 levels of fat supplementation; 33 g of crude fat per kg of dry matter (DM) or 64 g of crude fat per kg of DM for low and high fat diets, respectively, and 2 levels of 3-NOP; 0 mg/kg DM or 80 mg/kg DM. In total, 4 diets were formulated: low fat (LF), high fat (HF), 3-NOP and low fat (3LF), and 3-NOP and high fat (3HF). Cows were fed ad libitum and milked twice daily. The adaptation period lasted 11 d, followed by 5 d with 12 diurnal sampling times of digesta and ruminal fluid. Thereafter, gas exchange was measured for 5 d in respiration chambers. Chromic oxide and titanium dioxide were used as external flow markers to determine intestinal nutrient flow. No interactions between fat supplementation and 3-NOP were observed for methane yield (g/kg DM), total-tract digestibility of nutrients or total volatile fatty acid (VFA) concentration in the rumen. Methane yield (g/kg DMI) was decreased by 24% when cows were fed 3-NOP. In addition, 3-NOP increased carbon dioxide and hydrogen yield (g/kg DM) by 6% and 3,500%, respectively. However, carbon dioxide production was decreased when expressed on a daily basis. Fat supplementation did not affect methane yield but tended to reduce methane in percent of gross energy intake. A decrease (11%) in DMI was observed, when cows were fed 3-NOP. Likely, the lower DMI mediated a lower passage rate causing the tendency to higher rumen and total-tract neutral detergent fiber digestibility, when the cows were fed 3-NOP. Total VFA concentrations in the rumen were negatively affected both by 3-NOP and fat supplementation. Furthermore, 3-NOP caused a shift in the VFA fermentation profile, with decreased acetate proportion and increased butyrate proportion, whereas propionate proportion was unaffected. Increased concentrations of the alcohols methanol, ethanol, propanol, butanol, and 2-butanol were observed in the ruminal fluid when cows were fed 3-NOP. These changes in rumen metabolites indicate partial re-direction of hydrogen into other hydrogen sinks, when methanogenesis is inhibited by 3-NOP. In conclusion, fat supplementation did not reduce methane yield, whereas 3-NOP reduced methane yield, irrespective of fat level. However, the concentration of 3-NOP and diet composition and resulting desired mitigation effect must be considered before implementation. The observed reduction in DMI with 80 mg 3-NOP/kg DM was intriguing and may indicate that a lower dose should be applied in a Northern European context; however, the mechanism behind needs further investigation.

Subcritical water treatment to modify insoluble dietary fibers from brewer’s spent grain for improved functionality and gut fermentability

Lactic acid (LA)-assisted subcritical water treatment (SWT) was applied to modify the insoluble dietary fiber (IDF) from brewer’s spent grain (BSG) for enhancing its functionality and gut fermentability. Modified IDFs were thoroughly characterized for their chemical and structural properties. The results revealed that increasing the treatment temperature and LA concentration reduced hemicellulose content in IDFs from 38.4 % to 0.7 %, alongside a decreased yield (84.8 %–51.4 %), reduced particle size (519.8–288.6 μm), and more porous structure of IDFs. These modifications were linked to improved functionalities, evidenced by the highest water and oil holding capacity increasing by 36 % and 67 %, respectively. Remarkably, the highest glucose adsorption capacity increased by 6.5 folds. Notably, modified IDFs exhibited slower in-vitro fermentation, elevated short-chain fatty acids (SCFAs) production, and a higher proportion of butyrate in SCFAs. These findings highlight the potential of LA-assisted SWT in transforming BSG-derived IDF into a valuable functional food ingredient.

Fucose modifies short chain fatty acid and H2S formation through alterations of microbial cross-feeding activities.

Algae are a rich but unexplored source of fibers with the potential to contribute to the next generation of prebiotics. The sulfated brown algae polysaccharide, fucoidan, is mainly composed of the deoxy-hexose L-fucose, which can be metabolized to 1,2-propanediol (1,2-PD) or lactate by gut microbes as precursors of propionate and butyrate. It was the aim of this study to investigate the impact of fucoidan on the fermentation capacity of the fecal microbiota and to compare to fucose. In batch fermentations of fecal microbiota collected from 17 donor samples, fucose promoted the production of propionate while no consistent effect was observed for commercial fucoidan and Fucus vesiculosus extract prepared in this study containing laminarin and fucoidan. H2S production was detected under all tested conditions, and levels were significantly lower in the presence of fucose in a dose-dependent manner. The addition of high fucose levels led to higher relative abundance of microbial 1,2-PD and lactate cross-feeders. Our results highlight that fucose and not fucoidan addition impacted fermentation capacity and increased the proportions of propionate and butyrate, which allows for precise modulation of intestinal microbiota activity.

Effects of chromium propionate supplementation on lactation performance, nutrient digestibility, rumen fermentation patterns, and antioxidant status in Holstein cows under heat stress

Chromium propionate (CrP) supplementation has the potential effects on mitigating metabolic stress on dairy cows, however, the effect of increased CrP supply on alleviating heat stress of mid-lactation cows is rarely evaluated. This study was conducted to evaluate the effect of CrP supplementation on lactation performance, nutrient digestibility, rumen fermentation patterns, and antioxidant status in dairy cows under heat stress. Sixty-four Holstein dairy cows in mid-lactation with similar parity (2.1 ± 0.2), current milk production (40 ± 1.4 kg/d), and days in milk (143 ± 7.8 d) were randomly allocated to one of four treatments with a completely randomized design. After a 7-day adaptation period, cows were fed CrP at doses of 0, 4, 8, and 12 mg/d of Cr per head for 49 d. The average temperature humidity index (THI) was 77 during the experimental period. The average respiration rate and rectal temperature decreased quadratically (P < 0.01) with increasing CrP supplementation. Dry matter intake (DMI), milk yield, and milk lactose yield increased quadratically (P < 0.05) with increasing CrP supplementation, whereas 4% fat-corrected milk was not affected by treatments, and feed efficiency tended to decrease quadratically (P = 0.07). The percentage of milk protein and lactose increased linearly (P = 0.05) with increasing CrP supplementation, whereas milk urea-N concentration and somatic cell count decreased quadratically (P < 0.01). Although total-tract apparent digestibility of dry matter, organic matter, crude protein, and ether extract was not affected by CrP supplementation, neutral detergent fiber digestibility increased quadratically (P = 0.01) with increasing CrP supplementation. The concentrations of milk Cr and urinary Cr were not affected by CrP supplementation. Ruminal pH, the concentration of total VFA and ammonia-N, and the molar proportion of propionate and butyrate were not affected by treatments, whereas the molar proportion of acetate increased quadratically (P < 0.01) with increasing CrP supplementation. The blood urea-N concentration decreased quadratically (P < 0.01) and the concentration of glutathione peroxidase and superoxide dismutase increased quadratically (P < 0.01) with increasing CrP supplementation, while the ratio of glucose to insulin and the concentration of glucose and malonaldehyde did not differ among treatments. In conclusion, CrP supplementation could increase milk yield in mid-lactation cows under heat stress by increasing DMI, reducing respiration rate and rectal temperature, and improving antioxidant status. The recommended dose of CrP is 4–8 mg/d of Cr per cow in hot weather.

Characterization of rumen microbiota in lactating Holstein cows fed molasses versus corn grain at two levels of rumen-degradable protein

We evaluated the influence of diets differing in non-fiber carbohydrates and rumen-degradable protein (RDP) levels on changes in the ruminal bacterial populations in lactating Holstein cows. In all, 12 ruminally cannulated cows were assigned to diets with high or low RDP levels. Within each RDP level, molasses was substituted for corn grain at a concentration of 0%, 5.25%, or 10.5% of diet dry matter in a replicated 3 × 3 Latin square design with 28-day periods. Liquid and solid rumen digesta fractions collected at the end of each period underwent 16S rRNA gene sequencing to identify operational taxonomic units and were analyzed for short-chain fatty acids. Protein degradability affected 6 bacterial genera, whereas carbohydrate alteration impacted 13 genera (p &amp;lt; 0.05). Of the 30 genera with the highest relative abundance, 26 differed by digesta fraction (p &amp;lt; 0.05), with Bacteroidetes genera showing a greater abundance in solids and Firmicutes genera demonstrating a greater prevalence in liquids. Regarding relative abundances, with increasing molasses, Succiniclasticum decreased in liquid (p &amp;lt; 0.05), and CF231, YRC22, Clostridium, Desulfovibrio, BF311, and Oscillospira increased in solids (p &amp;lt; 0.05). In contrast, at higher RDP levels, Succiniclasticum increased while YRC22 and Pseudobutyrivibrio decreased in solids (p &amp;lt; 0.05). Genera with abundances found to be correlated with fermentation products in the liquid included Shuttleworthia, Treponema, Lachnospira, and Schwartzia, which typically have lower relative abundances, showing strong positive correlations with molar proportions (mol%) of propionate, butyrate, and valerate (p &amp;lt; 0.05), and negative correlations with pH and acetate mol% (p &amp;lt; 0.05). Fibrobacter was positively correlated with lactate mol% (p &amp;lt; 0.05). Butyrate mol% exhibited a quadratic increase as molasses increased (p = 0.017), and lactate mol% rose with increased RDP levels (p = 0.042). No treatment effects were detected for pH propionate and valerate mol%; however, we observed a tendency (p = 0.075) for a quadratic effect of molasses treatment on the mol% of acetate. These findings substantiate the pivotal role of diet in shaping rumen microbiota and metabolism, elucidating a nuanced relationship between dietary components, bacterial community structure, and metabolic output. This offers a more detailed understanding of rumen function and the potential for high-precision dietary management in lactating cows.

Effect of replacing corn straw by sweet sorghum silage or whole plant corn silage in sheep diets on rumen fermentation and bacterial flora.

Sweet sorghum silage (SS; Sorghum dochna 'Dochna') has been extensively studied in recent years as a supplementary forage-to-corn silage (CS; Zea mays L.), but there are still relatively few studies on its effects on the rumen environment of sheep. Determining the short-term impact of converting roughage from corn straws to SS compared to CS on rumen fermentation and bacterial population dynamics was the main goal of the current study. Twelve female thin-tailed Han sheep (29.8±1.34kg) were randomly divided into one of two treatments: concentrate supplemented with SS or CS, respectively. During the 15-day pretest period, concentrate was fed in two separate feedings at 0800h and 1800h, and ensure that the animals were all consumed within an hour of being fed. Thereafter, the animals had free access to corn straw. The feeding procedures during the pretest period were the same as during the measurement period. Rumen fluid was collected via sheep esophageal tube on the last day of adaptation phase (1-7 days) and stabilisation phase (8-30 days), respectively. The results showed that there was a similarity in the total concentration of VFA (volatile fatty acid) and the proportions of acetate, propionate, butyrate, and branched-chain VFA (P>0.05) and microbial diversity indices (P>0.05) between the two silage groups throughout the experimental period. The concentration of Ammonia nitrogen (P=0.001) and proportion of valerate (P=0.028) decreased in the CS and SS groups, respectively. The abundance and predicted function of rumen bacteria in the SS group did not differ significantly (P>0.05) between the two measurement phases. However, the abundance of Prevotella_1 (P=0.038) was higher in the CS group than in the SS group at 7d. The abundances of Firmicutes (P=0.005) and Ruminococcaceae_NK4A214_group (P=0.002) increased, while the abundances of Bacteroidetes (P=0.044), Proteobacteria (P=0.046), and Prevotella_1 (P=0.009) decreased in the CS group at 30d. Genes related to pyruvate metabolism (P=0.020) were significantly higher at 30d than at 7d, whereas purine metabolism (P=0.007), pyrimidine metabolism (P=0.007), and metabolic pathways (P=0.010) were lower at 30d in the CS group. In conclusion, this study indicated that SS maintained a steady rumen environment, while CS caused high fluctuations in bacterial abundance and predicted function for sheep.

Lactation performance, milk fat output, and nutrient digestibility responses to the addition of liquid molasses or yeast culture in dairy cows fed super-conditioned corn

Increased diet fermentability may decrease ruminal pH and fiber digestibility, and increase the flow of trans fatty acids (FA) to the lower tract ultimately leading to milk fat depression. We recently showed that feeding super-conditioned corn, a new method of corn processing (95°C for 6 min in super-conditioner) for ruminants has potential to the reduction in milk fat yield caused by changes in ruminal pH and increased trans FA in milk fat. Supplementing yeast culture (YC) and replacing starch with sugar sources in diet can counteract the negative effects of high fermentable diets by improving ruminal pH and milk fat output. This study aimed to evaluate the effect of feeding beet liquid molasses (LM) and YC on intake and total-tract digestibility of nutrients, milk yield and composition, ruminal fermentation, milk FA profile, and plasma concentrations of glucose, nonesterified FA, β-hydroxybutyric acid, and urea N in early-lactation dairy cows fed high-starch diets containing super-conditioned corn. Twelve primiparous and 18 multiparous Holstein cows (mean ± SD; 67 ± 12 d in milk and 42 ± 2.1 kg of milk at the beginning of the experiment) were blocked by parity, pre-experimental milk yield, and DIM. Cows were used in a randomized complete block design experiment with 14 d as covariate period and 37 d for the experimental period. The following dietary treatments were fed as total mixed rations: (1) control diet (CTRL = no YC or LM supplementation), (2) LM supplementation at 5% of the diet dry matter (MOL diet), and (3) CTRL supplemented with 10 g/d of YC (YST diet). Diets were formulated to be isonitrogenous and isoenergetic. Intake of nutrients and apparent total-tract digestibility of crude protein and starch did not change across treatments. In contrast, cows fed the YST diet had the greatest apparent total-tract digestibility of dry matter, organic matter and neutral detergent fiber. Compared with the CTRL diet, yield of 4% FCM increased by 2.4 and 1.8 kg in cows fed MOL or YST, respectively. The ruminal molar proportions of acetate and butyrate increased in cows fed the YST or MOL diets, respectively, but the proportion of ruminal propionate was not affected by treatments. Milk fat concentration increased by supplementing both LM and YC and the milk yield of total trans-18:1 dropped by 45% and 18% relative to CTRL with MOL or YST diets, respectively. While the MOL diet increased the milk proportion and yield of de novo FA, no treatment effects were observed for the proportion and yield of preformed FA in the milk fat. Apart from β-hydroxybutyric acid concentration in plasma, which was greatest in cows fed MOL, remaining blood metabolites were not affected by treatments. Overall, MOL and YST diets increased 4% FCM and milk fat concentration and reduced the proportion of total trans-18:1 FA in milk fat in cows fed a concentrate based on super-conditioned corn. These responses were associated with increased ruminal pH and the molar proportions of acetate and butyrate with feeding the MOL and YST diets.

Screening macroalgae for mitigation of enteric methane in vitro

This study investigated the effects of 67 species of macroalgae on methanogenesis and rumen fermentation in vitro. Specimens were analyzed for their effect on ruminal fermentation and microbial community profiles. Incubations were carried out in an automated gas production system for 24-h and macroalgae were tested at 2% (feed dry matter basis) inclusion rate. Methane yield was decreased 99% by Asparagopsis taxiformis (AT) when compared with the control. Colpomenia peregrina also decreased methane yield 14% compared with control; no other species influenced methane yield. Total gas production was decreased 14 and 10% by AT and Sargassum horneri compared with control, respectively. Total volatile fatty acid (VFA) concentration was decreased between 5 and 8% by 3 macroalgae, whereas AT reduced it by 10%. Molar proportion of acetate was decreased 9% by AT, along with an increase in propionate by 14%. Asparagopsis taxiformis also increased butyrate and valerate molar proportions by 7 and 24%, respectively, whereas 3 macroalgae species decreased molar proportion of butyrate 3 to 5%. Vertebrata lanosa increased ammonia concentration, whereas 3 other species decreased it. Inclusion of AT decreased relative abundance of Prevotella, Bacteroidales, Firmicutes and Methanobacteriaceae, whereas Clostridium, Anaerovibrio and Methanobrevibacter were increased. Specific gene activities for Methanosphaera stadtmane and Methanobrevibacter ruminantium were decreased by AT inclusion. In this in vitro study, Asparagopsis taxiformis was most effective in decreasing methane concentration and yield, but also decreased total gas production and VFA concentration which indicates overall inhibition of ruminal fermentation. No other macroalgae were identified as potential mitigants of enteric methane.

Effect of substituting maize silage with fresh or ensiled sugar beets on nutrient digestibility, rumen fermentation and microbial synthesis, and enteric methane emission in dairy cows

This study aimed to 1) examine nutrient digestibility, rumen fermentation and microbial synthesis, and enteric methane emission when feeding diets high in sugar content provided as freshly stored or ensiled sugar beets to dairy cows, and 2) to evaluate the methane mitigation potential of ensiled sugar beets with different nutrient composition (sugar vs. alcohol) by use of an additive during ensiling. Four rumen, duodenal and ileal fistulated Danish Holstein dairy cows were used in a 4 × 4 Latin square design with 21-d periods. Maize silage was included in the control diet (CON) and was partially replaced in the experimental diets with either freshly stored sugar beets (SBF), ensiled beets with ensiling additive (SBE+), or ensiled beets without ensiling additive (SBE−) at 196 g/kg dietary dry matter (DM) content. Cows adapted to the diets for 11 d, after which rumen liquid and digesta were collected over 5 d, and gas exchange was measured in respiration chambers over the next 5 d. Dry matter intake (DMI), daily methane production, and methane per kg organic matter (OM) intake, rumen digested OM, and energy-corrected milk (ECM) yield were unaffected by diet. Methane per kg DMI (tendency) and per kg OM intake was lower for SBE– compared to SBF. Nutrient digestibility of DM, OM, starch, and neutral detergent fibre in different sections of the digestive tract were unaffected by diet. Molar proportion of acetate in rumen liquid decreased for ensiled sugar beet diets relative to CON, while molar proportions of propionate and acetate-to-propionate ratio remained unaffected. Molar proportion of butyrate was higher for SBE+ than CON. Microbial crude protein synthesis and microbial efficiency were unaffected by diet. Milk yield and ECM yield (tendency) were lower for SBE+ than CON. In conclusion, freshly stored sugar beets and sugar beets ensiled with or without additive, can replace maize silage in dairy cattle rations without adverse effects on DMI, rumen fermentation, and nutrient digestibility, and without altering most expressions of methane emissions, but methane per kg of OM intake was lower for beets ensiled without additive compared to freshly stored beets. The ECM yield, however, tends to be lowered for ensiled beets with additive.

The impact of cancer cachexia on gut microbiota composition and short-chain fatty acid metabolism in a murine model

This study investigates the relationship between cancer cachexia and the gut microbiota, focusing on the influence of cancer on microbial composition. Lewis lung cancer cell allografts were used to induce cachexia in mice, and body and muscle weight changes were monitored. Fecal samples were collected for targeted metabolomic analysis for short chain fatty acids and microbiome analysis. The cachexia group exhibited lower alpha diversity and distinct beta diversity in gut microbiota compared to the control group. Differential abundance analysis revealed higher Bifidobacterium and Romboutsia, but lower Streptococcus abundance in the cachexia group. Additionally, lower proportions of acetate and butyrate were observed in the cachexia group. The study observed that a significant impact of cancer cachexia on gut microbiota and their generated metabolites, indicating the host-to-gut microbiota axis.