4,4-Diallyl curcumin bis(2,2-hydroxymethyl)propanoate ameliorates nonalcoholic steatohepatitis in methionine-choline-deficient diet and Western diet mouse models.

Nonalcoholic steatohepatitis (NASH) is a progressive form of nonalcoholic fatty liver disease (NAFLD) that causes severe liver damage, fibrosis, and scarring. Despite its potential to progress to cirrhosis or hepatic failure, approved drugs or treatments are currently unavailable. We developed 4,4-diallyl curcumin bis(2,2-hydroxymethyl)propanoate, also known as 35e, which induces upregulation of mitochondrial proteins including carnitine palmitoyltransferase I (CPT-I), carnitine palmitoyltransferase II, heat shock protein 60, and translocase of the outer mitochondrial membrane 20. Among these proteins, the upregulated expression of CPT-I was most prominent. CPT-I plays a crucial role in transporting carnitine across the mitochondrial inner membrane, thereby initiating mitochondrial ß-oxidation of fatty acids. Given recent research showing that CPT-I activation could be a viable pathway for NASH treatment, we hypothesized that 35e could serve as a potential agent for treating NASH. The efficacy of 35e in treating NASH was evaluated in methionine- and choline-deficient (MCD) diet- and Western diet (WD)-induced models that mimic human NASH. In the MCD diet-induced model, both short-term (2 weeks) and long-term (7 weeks) treatment with 35e effectively regulated elevated serum alanine aminotransferase (ALT)/aspartate aminotransferase (AST) concentrations and histological inflammation. However, the antisteatotic effect of 35e was obtained only in the short-term treatment group. As a comparative compound in the MCD diet-induced model, curcumin treatment did not produce significant regulatory effects on the liver triglyceride/total cholesterol, serum ALT/AST, or hepatic steatosis. In the WD-induced model, 35e ameliorated hepatic steatosis and hepatic inflammation, while increasing serum AST and hepatic lipid content. A decrease in epididymal adipose tissue weight and serum free fatty acid concentration suggested that 35e may promote lipid metabolism or impede lipid accumulation. Overall, 35e displayed significant antilipid accumulation and antifibrotic effects in the two complementary mice models. The development of new curcumin derivatives with the ability to induce CPT-I upregulation could further underscore their efficacy as anti-NASH agents.

Effect of rice bran fermented with Ligilactobacillus equi on in vitro fermentation profile and microbial population.

This study was conducted to assess the effects of fermented rice bran (FRB) with Ligilactobacillus equi on ruminal fermentation using an in vitro system. Oat hay, corn starch, and wheat bran were used as substrate for control. Ten percent of wheat bran was replaced with rice bran (RB), rice bran fermented with distilled water, and rice bran fermented with L. equi for T1, T2, and T3, respectively. The experimental diets were mixed with buffered rumen fluid from wethers under nitrogen gas and incubated for 24 h at 39°C. The fermentation profile and microbial population were analyzed after the incubations. The results revealed that the RB and FRB (with or without L. equi) significantly reduced the gas, methane (CH4), and CH4 per dry matter digested (p < 0.001). Total short-chain fatty acid was also reduced in T1 and T2 in comparison with the control (p < 0.001). Propionate proportion was increased while butyrate proportion was reduced in response to treatment addition in cultures (p < 0.001). Anaerobic fungi and Fibrobacter succinogenes abundance were decreased in treatments (p < 0.001). Overall, CH4 production in vitro can be reduced by RB and FRB supplementation as a result of the reduction of fiber-degrading microorganisms and a decrease in gas production.

Adlercreutzia faecimuris sp. nov., producing propionate and acetate isolated from mouse feces.

A novel strictly anaerobic bacterium, strain JBNU-10 T, was isolated from BALB/c mouse feces. Cells of the strain JBNU-10 T were Gram-stain positive, non-motile and rod-shaped. Optimum growth occurred at 37℃, with 1% (w/v) NaCl and at pH 7. Phylogenetic analysis based on 16S rRNA gene sequence showed that strain JBNU-10 T belonged to the genus Adlercreutzia and were closely related to Adlercreutzia muris WCA-131-CoC-2 T (95.90%). The genome sequencing of strain JBNU-10 T revealed a genome size of 2,790,983 bp, a DNA G + C content of 69.4 mol%. It contains a total of 2,266 CDSs, 5 rRNA genes and 49 tRNA genes. According to the data obtained strain JBNU-10 T shared ANI value below 77.6- 67.7%, dDDH value below 23.8% with the closely type species. Strain JBNU-10 T possessed iso-C16:0 DMA, C18:1 CIS 9 FAME, and C18:0 DMA as the major fatty acids and had DMMK-6. The major end products of fermentation is propionate and acetate. Based on phylogenetic, physiological and chemotaxonomic characteristics, strain JBNU-10 T represent a novel species of the genus Adlercreutzia. The type strain is JBNU-10 T (= KCTC 25028 T = CCUG 75610 T).

Exploring rumen fermentation and microbial populations in Dhofari goats fed a chitosan-added diet.

The use of chitosan (CHI) in ruminant diets is a promising natural modifier for rumen fermentation, capable of modulating both the rumen pattern and microbial activities. The objective of this study was to explore the rumen fermentation and microbial populations in Dhofari goats fed a diet supplemented with CHI. A total of 24 Dhofari lactating goats (body weight, 27.32 ± 1.80 kg) were assigned randomly into three experimental groups (n = 8 ewes/group). Goats were fed a basal diet with either 0 (control), 180 (low), or 360 (high) mg CHI/kg of dietary dry matter (DM) for 45 days. Feeding high CHI linearly increased (p < 0.05) the propionate level and reduced the acetate, butyrate, and total protozoa count (p < 0.05). Ruminal ammonia nitrogen (NH3-N) concentrations and the acetate:propionate ratio decreased linearly when goats were fed CHI (p < 0.05). The abundances of both Spirochetes and Fibrobacteres phyla were reduced (p < 0.05) with both CHI doses relative to the control. Both low and high CHI reduced (p < 0.05) the relative abundances of Butyrivibrio hungatei, Fibrobacter succinogenes, Ruminococcus albus, Ruminococcus flavefaciens, Selenomonas ruminantium and Neocallimastix californiae populations. Adding CHI significantly decreased (p < 0.05) the abundances of Ascomycota, Basidiomycota, and Bacillariophyta phyla compared to the control. Adding CHI to the diet reduces the abundance of fibrolytic-degrading bacteria, however, it increases the amylolytic-degrading bacteria. Application of 360 mg of CHI/kg DM modified the relative populations of ruminal microbes, which could enhance the rumen fermentation patterns in Dhofari goats.

Effects of dietary forage neutral detergent fiber and rumen degradable starch ratios on chewing activity, ruminal fermentation, ruminal microbes and nutrient digestibility of Hu sheep fed a pelleted total mixed ration.

Pelleted total mixed ration (P-TMR) feeding, which has become a common practice in providing nutrition for fattening sheep, requires careful consideration of the balance between forage neutral detergent fiber (FNDF) and rumen degradable starch (RDS) to maintain proper rumen functions. The present study aimed to investigate the effects of the dietary FNDF/RDS ratio (FRR) on chewing activity, ruminal fermentation, ruminal microbes, and nutrient digestibility in Hu sheep fed a P-TMR diet. This study utilized eight ruminally cannulated male Hu sheep, following a 4 × 4 Latin square design with 31 d each period. Diets consisted of four FRR levels: 1.0 (high FNDF/RDS ratio, HFRR), 0.8 (middle high FNDF/RDS ratio, MHFRR), 0.6 (middle low FNDF/RDS ratio, MLFRR), and 0.4 (low FNDF/RDS ratio, LFRR). Reducing the dietary FRR levels resulted in a linear decrease in ruminal minimum pH and mean pH, while linearly increasing the duration and area of pH below 5.8 and 5.6, as well as the acidosis index. Sheep in the HFRR and MHFRR groups did not experience subacute ruminal acidosis (SARA), whereas sheep in another two groups did. The concentration of total volatile fatty acid and the molar ratios of propionate and valerate, as well as the concentrate of lactate in the rumen linearly increased with reducing dietary FRR, while the molar ratio of acetate and acetate to propionate ratio linearly decreased. The degradability of NDF and ADF for alfalfa hay has a quadratic response with reducing the dietary FRR. The apparent digestibility of dry matter, organic matter, neutral detergent fiber, and acid detergent fiber linearly decreased when the dietary FRR was reduced. In addition, reducing the dietary FRR caused a linear decrease in OTUs, Chao1, and Ace index of ruminal microflora. Reducing FRR in the diet increased the percentage of reads assigned as Firmicutes, but it decreased the percentage of reads assigned as Bacteroidetes in the rumen. At genus level, the percentage of reads assigned as Prevotella, Ruminococcus, Succinivibrio, and Butyrivibrio linearly decreased when the dietary FRR was reduced. The results of this study demonstrate that the dietary FRR of 0.8 is crucial in preventing the onset of SARA and promotes an enhanced richness of ruminal microbes and also improves fiber digestibility, which is a recommended dietary FRR reference when formulating P-TMR diets for sheep.

Forage neutral detergent fiber (FNDF) and rumen degradable starch (RDS) are key components of carbohydrates in the diet for ruminants, which would reflect saliva secretion and the acid production potential of feed. However, appropriate FNDF to RDS ratios (FRR) applicable to ruminants under the condition of pelleted total mixed ration (P-TMR) feeding have not been reported. In this study, we investigated the effects of the dietary FRR on chewing activity, ruminal fermentation, ruminal microbial communities, and nutrient digestibility of Hu sheep under P-TMR feeding. The results indicate that reducing dietary FRR levels would induce acidosis in sheep, which negatively affected fiber utilization and ruminal bacterial communities. The FRR of 0.8 was a recommended dietary FRR when formulating a P-TMR diet for fattening sheep, as indicated by decreased ruminal acidosis risk and increased richness of ruminal microbes in the rumen as well as nutrient digestibility.

Reverse electron transfer: Novel anaerobic methanogenesis pathway regulated through exogenous CO2 synergized with biochar.

Acid accumulation and carbon emission are two major challenges in anaerobic digestion. Syntrophic consortia can employ reverse electron transfer (RET) to facilitate thermodynamically unfavorable redox reactions during acetogenesis. However, the potential mechanisms and regulatory methods of RET remain unclear. This study examines the regulatory mechanisms by which exogenous CO2 affects RET and demonstrates that biochar maximizes CO2 solubility at 25.8 mmol/L to enhance effects further. CO2 synergized with biochar significantly increases cumulative methane production and propionate degradation rate. From the bioenergetic perspective, CO2 decreases energy level to a maximum of -87 kJ/mol, strengthening the thermodynamic viability. The underlying mechanism can be attributed to RET promotion, as indicated by increased formate dehydrogenase and enrichment of H2/formate-producing bacteria with their partner Methanospirillum hungatei. Moreover, the 5 % 13CH4 and methane contribution result show that CO2 accomplishes directed methanogenesis. Overall, this investigation riches the roles of CO2 and biochar in AD surrounding RET.

Rumen fermentation parameters and papillae development in Simmental growing bulls with divergent residual feed intake.

Residual feed intake (RFI), a widespread index used to measure animal feed efficiency, is influenced by various individual biological factors related to inter-animal variation that need to be assessed. Herein, 30 Simmental bulls, raised under the same farm conditions, were divided on the basis of RFI values into a high efficient group (HE, RFI =  - 1.18 ± 0.33 kg DM/d, n = 15) and a low efficient group (LE, RFI = 0.92 ± 0.35 kg DM/d, n = 15). Subsequently, bulls were slaughtered at an average BW of 734 ± 39.4 kg. Their ruminal fermentation traits were analysed immediately after slaughtering and after 24 h of in vitro incubation. Furthermore, ruminal micro-biota composition and ruminal papillae morphology were examined. The LE group exhibited a higher propionate concentration as a percentage of total volatile fatty acids (17.3 vs 16.1%, P = 0.04) in the rumen fluid collected during slaughtering, which was also confirmed after in vitro fermentation (16.6 vs 15.4% respectively for LE and HE, P = 0.01). This phenomenon resulted in a significant alteration in the acetate-to-propionate ratio (A:P) with higher values for the HE group, both after slaughter (4.01 vs 3.66, P = 0.02) and after in vitro incubation (3.78 vs 3.66, P = 0.02). Methane production was similar in both groups either as absolute production (227 vs 218 mL for HE and LE, respectively) or expressed as a percentage of total gas (approximately 22%). Even if significant differences (P < 0.20) in the relative abundance of some bacterial genera were observed for the two RFI groups, no significant variations were observed in the alpha (Shannon index) and beta (Bray-Curtis index) diversity. Considering the papillae morphology, the LE subjects have shown higher length values (6.26 vs 4.90 mm, P < 0.01) while HE subjects have demonstrated higher papillae density (46.4 vs 40.5 n/cm2, P = 0.02). Histo-morphometric analysis did not reveal appreciable modifications in the total papilla thickness, boundaries or surface between the experimental groups. In conclusion, our results contribute to efforts to analyse the factors affecting feed efficiency at the ruminal level. Propionate production, papillae morphology and a few bacterial genera certainly play a role in this regard, although not a decisive one.

Potential mechanisms of propionate degradation and methanogenesis in anaerobic digestion coupled with microbial electrolysis cell system: Importance of biocathode.

Microbial electrolysis cells (MEC) have the potential for enhancing the efficiency of anaerobic digestion (AD). In this study, microbiological and metabolic pathways in the biocathode of anaerobic digestion coupled with microbial electrolysis cells system (AD-MEC) were revealed to separate bioanode. The biocathode efficiently degraded 90 % propionate within 48 h, leading to a methane production rate of 3222 mL·m-2·d-1. The protein and heme-rich cathodic biofilm enhanced redox capacity and facilitated interspecies electron transfer. Key acid-degrading bacteria, including Dechloromonas agitata, Ignavibacteriales bacterium UTCHB2, and Syntrophobacter fumaroxidans, along with functional proteins such as cytochrome c and e-pili, established mutualistic relationships with Methanothrix soehngenii. This synergy facilitated a multi-pathway metabolic process that converted acetate and CO2 into methane. The study sheds light on the intricate microbial dynamics within the biocathode, suggesting promising prospects for the scalable integration of AD-MEC and its potential in sustainable energy production.

The gut commensal Blautia maintains colonic mucus function under low-fiber consumption through secretion of short-chain fatty acids.

Beneficial gut bacteria are indispensable for developing colonic mucus and fully establishing its protective function against intestinal microorganisms. Low-fiber diet consumption alters the gut bacterial configuration and disturbs this microbe-mucus interaction, but the specific bacteria and microbial metabolites responsible for maintaining mucus function remain poorly understood. By using human-to-mouse microbiota transplantation and ex vivo analysis of colonic mucus function, we here show as a proof-of-concept that individuals who increase their daily dietary fiber intake can improve the capacity of their gut microbiota to prevent diet-mediated mucus defects. Mucus growth, a critical feature of intact colonic mucus, correlated with the abundance of the gut commensal Blautia, and supplementation of Blautia coccoides to mice confirmed its mucus-stimulating capacity. Mechanistically, B. coccoides stimulated mucus growth through the production of the short-chain fatty acids propionate and acetate via activation of the short-chain fatty acid receptor Ffar2, which could serve as a new target to restore mucus growth during mucus-associated lifestyle diseases.

Dietary Supplementation of Vitamin B12 to Rats Fed High-Amylose Cornstarch Normalizes Propionate Fermentation in the Colon.

Since propionate exerts several physiological effects, maintenance of its normal colonic fermentation is essential. To investigate whether vitamin B12 (VB12) is essential for normal propionate fermentation by colonic bacteria, via the succinate pathway, we examined if high-amylose cornstarch (HACS) feeding activated such a pathway, if high HACS feeding impaired propionate fermentation, and if oral VB12 supplementation normalized propionate fermentation. Male rats were given control, 20% HACS or 3% fucose diets (Expt. 1); a VB12-free control diet or one supplemented with 5-30% HACS (Expt. 2); and the 20% HACS diet supplemented with 0.025-25 mg/kg of VB12 (Expt. 3), for 14 d. HACS feeding significantly increased cecal succinate concentration, activating the succinate pathway (Expt. 1). Cecal cobalamin concentration in 20% and 30% HACS groups was about 75% of that in the control group (Expt. 2). Cecal succinate and propionate concentrations significantly increased and decreased in 30% HACS groups, respectively, compared with the control group. Although HACS group supplemented with 0.025 mg/kg of VB12 had a low concentration of cecal propionate, adding high amounts of VB12 to HACS diets provided sufficient amounts of VB12 to rat ceca and increased cecal propionate concentration (Expt. 3). Compared with the non-HACS group, the relative abundance of Akkermansia muciniphila, but not Bacteroides/Phocaeicola, was lower in the HACS counterpart and showed improvement with increased VB12 doses. To summarize, feeding high HACS decreased and increased cecal VB12 and succinate concentrations, respectively. Furthermore, colonic delivery of sufficient amounts of VB12 to rats likely reduced accumulation of succinate and normalized propionate fermentation.

Improving feed intake and rumen fermentation in lambs using mixed-dimensional attapulgite clay to adsorb naturally occurring mycotoxins.

This experiment was conducted to evaluate the effects of including a mixed-dimensional attapulgite clay (MDA) into a naturally moldly diet for Hu lambs. Fifty male Hu lambs with similar initial body weight (28.24 ±â€…1.80 kg) were randomly allocated into five dietary treatments: a basal diet containing naturally occurring mycotoxins with 0, 0.5, 1.0, and 2.0 kg/t MDA, and basal diet with a commercial mycotoxin adsorbent Solis with montmorillonite as the major component at 1 kg/t. Both MDA and Solis increased average daily gain (ADG) and dry matter intake (DMI; P ≤ 0.004), and there was no difference in growth performance between MDA and Solis (P ≥ 0.26). The final body weight, DMI, and ADG were linearly increased with increasing MDA supplementation (P < 0.01). Lambs treated with both MDA and Solis demonstrated greater apparent digestibility of dry matter (DM), organic matter (OM), and energy compared with the control group (P ≤ 0.03), and there were no differences in nutrient digestibilities between MDA and Solis (P ≥ 0.38). Digestibility of CP was linearly increased with the increasing MDA supplementation (P = 0.01). Neither MDA nor Solis affected rumen total volatile fatty acid (TVFA) concentration (P ≥ 0.39), but decreased the acetate-to-propionate ratio and molar proportion of n-butyrate (P ≤ 0.01), and MDA also increased the concentration of ammonia (P = 0.003). Besides, increasing MDA supplementation linearly reduced the acetate-to-propionate ratio and molar proportion of n-butyrate (P = 0.01), but linearly and quadratically increased the concentration of ammonia (P ≥ 0.003). These results showed that the incorporation of MDA into a naturally moldy diet of Hu lambs yielded comparable results to the Solis product, with higher growth performance and nutrient digestibility but lower acetate-to-propionate ratio observed. In conclusion, including ≥ 1 kg/t of MDA in high mycotoxin risk diets for growing lambs improves feed intake and rumen fermentation.

The issue of mycotoxin-contaminated animal feed has consistently presented a significant challenge in relation to animal health and production. The mixed-dimensional attapulgite clay (MDA) has been proven effective in binding polar mycotoxins such as aflatoxin, while also effectively adsorbing hydrophobic or weakly polar mycotoxins such as zearalenone (ZEN) and ochratoxin. Therefore, this study was undertaken to assess the impact of MDA inclusion in mycotoxin-contaminated diets on performance and rumen fermentation variables in lambs. The results indicated that MDA not only significantly improved the growth performance and nutrient digestibility of Hu lambs but also enhanced the molar proportion of propionate and ammonia concentration, and reduced the acetate to propionate ratio and the molar proportion of n-butyrate.

Novel oxidising feed additives reduce in vitro methane emissions using the rumen simulation technique.

Enteric methane (CH4) produced by ruminant livestock is a potent greenhouse gas and represents significant energy loss for the animal. The novel application of oxidising compounds as antimethanogenic agents with future potential to be included in ruminant feeds, was assessed across two separate experiments in this study. Low concentrations of oxidising agents, namely urea hydrogen peroxide (UHP) with and without potassium iodide (KI), and magnesium peroxide (MgO2), were investigated for their effects on CH4 production, total gas production (TGP), volatile fatty acid (VFA) profiles, and nutrient disappearance in vitro using the rumen simulation technique. In both experiments, the in vitro diet consisted of 50:50 grass silage:concentrate on a dry matter basis. Treatment concentrations were based on the amount of oxygen delivered and expressed in terms of fold concentration. In Experiment 1, four treatments were tested (Control, 1× UHP + KI, 1× UHP, and 0.5× UHP + KI), and six treatments were assessed in Experiment 2 (Control, 0.5× UHP + KI, 0.5× UHP, 0.25× UHP + KI, 0.25× UHP, and 0.12× MgO2). All treatments in this study had a reducing effect on CH4 parameters. A dose-dependent reduction of TGP and CH4 parameters was observed, where treatments delivering higher levels of oxygen resulted in greater CH4 suppression. 1× UHP + KI reduced TGP by 28 % (p = 0.611), CH4% by 64 % (p = 0.075) and CH4 mmol/g digestible organic matter by 71 % (p = 0.037). 0.12× MgO2 reduced CH4 volume by 25 % (p > 0.05) without affecting any other parameters. Acetate-to-propionate ratios were reduced by treatments in both experiments (p < 0.01). Molar proportions of acetate and butyrate were reduced, while propionate and valerate were increased in UHP treatments. High concentrations of UHP affected the degradation of neutral detergent fibre in the forage substrate. Future in vitro work should investigate alternative slow-release oxygen sources aimed at prolonging CH4 suppression.

Operational mode and powdered activated carbon promoting syntrophic propionate oxidation during anaerobic digestion of complex organic substances.

Operational mode and powdered activated carbon (PAC) are key factors facilitating microbial syntrophy and interspecies electron transfer during anaerobic digestion, consequently benefiting process stability and efficient methanogenesis. In this study, continuous-flow reactor (CFR) and sequencing batch reactor (SBR), with and without the addition of PAC, respectively, were operated to examine their effects on system performance and methanogenic activity. Based on the cycle-test result, the PAC-amended CFR (CFRPAC) recorded both the highest methane yield (690.1 mL/L) and the maximum CH4 production rate (28.8 mL/(L·h)), while SBRs exhibited slow methanogenic rates. However, activity assays indicated that SBRs were beneficial for organics removal in batch experiments fed with peptone. Taxonomic and functional analysis confirmed that CFRs were optimal for proliferating oligotrophs (e.g., Geobacter) and SBRs were more suitable for copiotrophs (e.g., Desulfobulbus). Metagenomic analysis revealed that CFRs had efficient acetate metabolic pathways from propionate and ethanol, whereas SBRs did not, resulting in the buildup of propionate. Furthermore, Methanobacterium and Methanothrix were acclimated to the different operational conditions, while acetoclastic Methanosarcina and hydrogenotrophic Methanolinea were acclimated in SBRs (5.1-13.4%) and CFRs (0.3-1.7%), respectively. This study confirmed the enhancement of microbial syntrophy by the addition of PAC as well as the acclimation of electroactive bacteria (e.g., Geobacter) with complex organic substances.

The effects of including sprouted barley with alfalfa hay in the diet on ruminal health and performance of cow-calf pairs.

The world population is growing exponentially, increasing demand to produce high-quality protein for human consumption. Changes in weather patterns, drought, and decreased land resources due to urbanization have increased the strain on the agriculture sector to meet world demands. An alternative method to combat these issues and continue to produce high-quality livestock feed would be through a controlled environment vertical farming system. Commonly, cereal grains, such as barley, are used in these systems to produce livestock feed. However, there is little information on the viability of feeding sprouted grains to beef cattle. Two diets of either feeder-quality alfalfa hay (n = 10 pairs; ALF) or the same alfalfa hay and sprouted barley (SB; 12.6% dry matter [DM]; n = 10 pairs) were fed for 90 d to Angus pairs with a steer calf during mid to late lactation. On days 0 and 90, body weight (BW), milk, rumen fluid, and body condition score were collected from cows and hip height and BW were recorded for calves. On day 10, BW was recorded for cows and calves and rumen fluid was collected from cows. Rumen fluid was also collected from cows on day 45. On day 55, BW was collected for both cows and calves and milk from cows. Intake was recorded throughout the trial via bunks with Vytelle technology. The PROC MIXED procedure of SAS was used to analyze all data with the day as a repeated measure to determine the main effect of diet. Individual volatile fatty acids (VFA) were measured as a percent of total VFA. No differences (P ≥ 0.16) were observed in calf BW, hip height, milk protein, fat, lactose, calf DM intake (DMI), or cow DMI. Cows fed SB tended (P = 0.08) to have a decreased somatic cell count compared to ALF. Percent butyrate was impacted by diet × day (P = 0.02), but no difference (P > 0.09) at any time points were detected. Additionally, a diet × day effect (P = 0.001) on rumen pH demonstrated that both groups stayed consistent until day 45 and then SB pH decreased the last 45 d. There was a day effect for total VFA (P = 0.0009), acetate:propionate (Ac:Pr; P < 0.0001), acetate (P < 0.0001), and propionate (P < 0.0001) demonstrating that total VFA, acetate, and Ac:Pr all increased throughout the trial, while propionate decreased. These results indicate that SB can be a potential alternative feed at this stage of production as it does not negatively impact health or production, but does affect the rumen pH and proportion of some VFA.

Climate variability and uncertainty associated with weather patterns can greatly impact feed security for cattle producers. Flooding, drought, and temperature extremes can reduce a farmer's ability to produce a consistent crop, resulting in feed prices that can fluctuate greatly. Vertical farming systems that sprout cereal grains in a controlled environment, using precision irrigation, may alleviate the effects of external factors such as climate and resulting feed prices. The objective of this study was to determine if sprouted barley (SB) could be used as an effective alternative feed source for cow-calf pairs. Two diets were fed to 20 cow-calf pairs, a control diet consisting of 100% feeder-quality alfalfa hay, or an experimental diet comprised of feeder-quality alfalfa hay and a 12.6% dry matter inclusion of SB for 90 d. Body weight, feed intake, and feeding behavior were analyzed in the cows and calves. Ruminal health was also assessed in cows by analyzing the ruminal fluid for pH and volatile fatty acid composition. When health and performance metrics were analyzed, no differences were found between the two diets that were administered to the cattle.

Integrating microbial abundance time series with fermentation dynamics of the rumen microbiome via mathematical modelling.

The rumen represents a dynamic microbial ecosystem where fermentation metabolites and microbial concentrations change over time in response to dietary changes. The integration of microbial genomic knowledge and dynamic modelling can enhance our system-level understanding of rumen ecosystem's function. However, such an integration between dynamic models and rumen microbiota data is lacking. The objective of this work was to integrate rumen microbiota time series determined by 16S rRNA gene amplicon sequencing into a dynamic modelling framework to link microbial data to the dynamics of the volatile fatty acids (VFA) production during fermentation. For that, we used the theory of state observers to develop a model that estimates the dynamics of VFA from the data of microbial functional proxies associated with the specific production of each VFA. We determined the microbial proxies using CowPi to infer the functional potential of the rumen microbiota and extrapolate their functional modules from KEGG (Kyoto Encyclopedia of Genes and Genomes). The approach was challenged using data from an in vitro RUSITEC experiment and from an in vivo experiment with four cows. The model performance was evaluated by the coefficient of variation of the root mean square error (CRMSE). For the in vitro case study, the mean CVRMSE were 9.8% for acetate, 14% for butyrate and 14.5% for propionate. For the in vivo case study, the mean CVRMSE were 16.4% for acetate, 15.8% for butyrate and 19.8% for propionate. The mean CVRMSE for the VFA molar fractions were 3.1% for acetate, 3.8% for butyrate and 8.9% for propionate. Ours results show the promising application of state observers integrated with microbiota time series data for predicting rumen microbial metabolism.

Combination effects of phytonutrient pellet and lemongrass (Cymbopogon citratus) powder on rumen fermentation efficiency and nutrient degradability using in vitro technique.

Phytonutrients (PTN) namely saponins (SP) and condensed tannins (CT) have been demonstrated to assess the effect of rumen fermentation and methane mitigation. Phytonutrient pellet containing mangosteen, rambutan, and banana flower (MARABAC) and lemongrass including PTN, hence these plant-phytonutrients supplementation could be an alternative plant with a positive effect on rumen fermentation. The aim of this experiment was to evaluate the effect of supplementation of MARABAC and lemongrass (Cymbopogon citratus) powder on in vitro fermentation modulation and the ability to mitigate methane production. The treatments were arranged according to a 3 × 3 Factorial arrangement in a completely randomized design. The two experimental factors consisted of MARABAC pellet levels (0%, 1%, and 2% of the total substrate) and lemongrass supplementation levels (0%, 1%, and 2% of the total substrate). The results of this study revealed that supplementation with MARABAC pellet and lemongrass powder significantly improved gas production kinetics (P < 0.01) and rumen fermentation end-products especially the propionate production (P < 0.01). While rumen methane production was subsequently reduced by both factors. Additionally, the in vitro dry matter degradability (IVDMD) and organic matter degradability (IVOMD) were greatly improved (P < 0.05) by the respective treatments. MARABAC pellet and lemongrass powder combination showed effective methane mitigation by enhancing rumen fermentation end-products especially the propionate concentration and both the IVDMD and IVOMD, while mitigated methane production. The combined level of both sources at 2% MARABAC pellet and 2% lemongrass powder of total substrates offered the best results. Therefore, MARABAC pellet and lemongrass powder supplementation could be used as an alternative source of phytonutrient in dietary ruminant.

RNA and protein biomarkers for detecting enhanced metabolic resistance to herbicides mesosulfuron-methyl and fenoxaprop-ethyl in black-grass (Alopecurus myosuroides).

BACKGROUND: The evolution of non-target site resistance (NTSR) to herbicides leads to a significant reduction in herbicide control of agricultural weed species. Detecting NTSR in weed populations prior to herbicide treatment would provide valuable information for effective weed control. While not all NTSR mechanisms have been fully identified, enhanced metabolic resistance (EMR) is one of the better studied, conferring tolerance through increased herbicide detoxification. Confirming EMR towards specific herbicides conventionally involves detecting metabolites of the active herbicide molecule in planta, but this approach is time-consuming and requires access to well-equipped laboratories. RESULTS: In this study, we explored the potential of using molecular biomarkers to detect EMR before herbicide treatment in black-grass (Alopecurus myosuroides). We tested the reliability of selected biomarkers to predict EMR and survival after herbicide treatments in both reference and 27 field-derived black-grass populations collected from sites across the UK. The combined analysis of the constitutive expression of biomarkers and metabolism studies confirmed three proteins, namely, AmGSTF1, AmGSTU2 and AmOPR1, as differential biomarkers of EMR toward the herbicides fenoxaprop-ethyl and mesosulfuron in black-grass. CONCLUSION: Our findings demonstrate that there is potential to use molecular biomarkers to detect EMR toward specific herbicides in black-grass without reference to metabolism analysis. However, biomarker development must include testing at both transcript and protein levels in order to be reliable indicators of resistance. This work is a first step towards more robust resistance biomarker development, which could be expanded into other herbicide chemistries for on-farm testing and monitoring EMR in uncharacterised black-grass populations. © 2024 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Metabolic rescue of α-synuclein-induced neurodegeneration through propionate supplementation and intestine-neuron signaling in C. elegans.

Microbial metabolites that can modulate neurodegeneration are promising therapeutic targets. Here, we found that the short-chain fatty acid propionate protects against α-synuclein-induced neuronal death and locomotion defects in a Caenorhabditis elegans model of Parkinson's disease (PD) through bidirectional regulation between the intestine and neurons. Both depletion of dietary vitamin B12, which induces propionate breakdown, and propionate supplementation suppress neurodegeneration and reverse PD-associated transcriptomic aberrations. Neuronal α-synuclein aggregation induces intestinal mitochondrial unfolded protein response (mitoUPR), which leads to reduced propionate levels that trigger transcriptional reprogramming in the intestine and cause defects in energy production. Weakened intestinal metabolism exacerbates neurodegeneration through interorgan signaling. Genetically enhancing propionate production or overexpressing metabolic regulators downstream of propionate in the intestine rescues neurodegeneration, which then relieves mitoUPR. Importantly, propionate supplementation suppresses neurodegeneration without reducing α-synuclein aggregation, demonstrating metabolic rescue of neuronal proteotoxicity downstream of protein aggregates. Our study highlights the involvement of small metabolites in the gut-brain interaction in neurodegenerative diseases.

A meta-analysis of methane-mitigation potential of feed additives evaluated in vitro.

A systematic literature review of in vitro studies was performed to identify methane (CH4) mitigation interventions with a potential to reduce CH4 emission in vivo. Data from 277 peer-reviewed studies published between 1979 and 2018 were reviewed. Individual CH4 mitigation interventions were classified into 14 categories of feed additives based on their type, chemical composition, and mode of action. Response variables evaluated were absolute CH4 emission (number of treatment means comparisons = 1,325); total volatile fatty acids (n = 1,007), acetate (n = 783), propionate (n = 792), and butyrate (n = 776) concentrations; acetate to propionate ratio (n = 675); digestibility of dry matter (n = 489), organic matter (n = 277), and neutral detergent fiber (n = 177). Total gas production was used as an explanatory variable in the model for CH4 production. Relative mean difference between treatment and control means reported in the studies was calculated and used for statistical analysis. The robust variance estimation method was used to analyze the effects of CH4 mitigation interventions. In vitro CH4 production was decreased by antibodies (-38.9%), chemical inhibitors (-29.2%), electron sinks (-18.9%), essential oils (-18.2%), plant extracts (-14.5%), plant inclusion (-11.7%), saponins (-14.8%), and tannins (-14.5%). Overall effects of direct-fed microbials, enzymes, macroalgae, and organic acids supplementation did not affect CH4 production in the current meta-analysis. When considering the effects of individual mitigation interventions containing a minimum number of 4 degrees of freedom within feed additives categories, Enterococcus spp. (i.e., direct-fed microbial), nitrophenol (i.e., electron sink), and Leucaena spp. (i.e., tannins) decreased CH4 production by 20.3%, 27.1%, and 23.5%, respectively, without extensively, or only slightly, affecting ruminal fermentation and digestibility of nutrients. It should be noted, however, that although the total number of publications (n = 277) and treatment means comparisons (n = 1,325 for CH4 production) in the current analysis were high, data for most mitigation interventions were obtained from less than 5 observations (e.g., maximum number of observations was 4, 7, and 22 for nitrophenol, Enterococcus spp., and Leucaena spp., respectively), because of limited data available in the literature. These should be further evaluated in vitro and in vivo to determine their true potential to decrease enteric CH4 production, yield, and intensity. Some mitigation interventions (e.g., magnesium, Heracleum spp., nitroglycerin, ß-cyclodextrin, Leptospermum pattersoni, Fructulus Ligustri, Salix caprea, and Sesbania grandiflora) decreased in vitro CH4 production by over 50% but did not have enough observations in the database. These should be more extensively investigated in vitro, and the dose effect must be considered before adoption of mitigation interventions in vivo.

Effects of acetyl groups on the prebiotic properties of glucomannan extracted from Artemisia sphaerocephala Krasch seeds.

This study explores the structural modification of glucomannan extracted from Artemisia sphaerocephala Krasch seeds (60S) to assess the impact of acetyl groups on its prebiotic characteristics. The structural changes were examined, with a focus on the degree of acetyl group substitution (DS). Both deacetylation and acetylation had limited influence on the molecular properties of 60S. Despite these modifications, the apparent viscosity of all samples remained consistently low. In vitro fermentation experiments revealed that Escherichia-Shigella decreased as DS increased, while Bacteroides ovatus was enriched. Acetylation had no significant impact on the utilization rate of 60S but led to a reduction in the production of propionic acid. Furthermore, untargeted metabolomics analysis confirmed the changes in propionic acid levels. Notably, metabolites such as N-acetyl-L-tyrosine, γ-muricholic acid, and taurocholate were upregulated by acetylated derivatives. Overall, acetyl groups are speculated to play a pivotal role in the prebiotic properties of 60S.