Butyrate Concentrations Research Articles

Cecal Microbial Diversity and Metabolome Reveal a Reduction in Growth Due to Oxidative Stress Caused by a Low-Energy Diet in Donkeys

Dietary energy level plays an important role in animal growth and development. The present study investigated the effect of dietary energy on the growth performance, antioxidative state, and nutrient digestion of meat donkeys. It simultaneously explored the probable reason for cecal microbiota and metabolome. Twelve meat donkeys (male) aged 1 year with a similar weight (150 ± 25 kg) were divided into two treatment groups: low-energy group (E1) and high-energy group (E2). The experiment was divided into a 10-day pre-trial period and a 135-day trial period. Donkeys in the trial periods were fed diets with digestible energy values (in dry matter) of 12.08 and 13.38 MJ/kg (pre-fattening, 1–45 d), 13.01 and 14.07 MJ/kg (mid-fattening, 46–90 d), and 13.54 and 14.93 MJ/kg (late-fattening, 91–135 d). The results show that E1 decreases body weight, average daily gain (ADG), and the digestibility of crude protein, ether extract, neutral detergent fiber, and acid detergent fiber (p < 0.05), but increases cecal acetate and butyrate concentrations, non-esterified fatty acids (NEFAs) in serum, and the ratio of dry matter intake to ADG(F/G). E1 diminished the activities of catalase and glutathione peroxidase, while it increased the content of interleukin, tumor necrosis factor-alpha, and reactive oxygen species (ROS) (p < 0.05). Cecal microbiome showed that the abundance of Firmicutes and Actinobacteria in E1 was significantly lower than in E2 (p = 0.029, p = 0.002), whereas Bacteroidetes was higher (p = 0.005). E1 increased the genera Ruminococcaceae-UCG-004, Acinetobacter, and Rikenellaceae_RC9_gut_group. Meanwhile, cecal metabolome showed that formyl-5-hydroxykynurenamine, chorismate, 3-sulfinoalanine, and 3-isopropylmalate were upregulated in E1, while brassinolide was downregulated. The altered metabolites were mainly enriched in metabolic pathways related to energy metabolism and metabolism to mitigate oxidative stress in the meat donkeys, such as tryptophan metabolism, brassinosteroid biosynthesis metabolism, etc. In conclusion, low-energy diets resulted in a negative energy balance in meat donkeys, resulting in more nutrients being oxidized to provide energy, inducing oxidative stress, and thereby leading to decreasing growth. The reduction in meat donkey growth from low-energy diets was related to changes in cecum microbiota and metabolites.

Is Butyrate Concentration in the Equine Gastrointestinal Tract Altered During and After Surgery for Treatment of Large Colon Obstruction?

A major cause of morbidity and mortality in horses with large colon obstructive lesions is injury to the colonic mucosal barrier from ischemic injury. Since butyrate has been shown to play a critical role in the maintenance of a healthy mucosal barrier, it may play a role in the recovery process. This study’s objective was to determine whether the differences in butyrate concentrations existed between horses with surgical large colon obstructive lesions and healthy horses both during and after surgery. Eleven horses presenting with surgical colic lesions were enrolled; colonic samples were acquired during surgery, and fecal samples were obtained 36 h later. Colonic and fecal samples were also obtained from control groups. Samples were analyzed for butyrate, acetate, and propionate concentrations. There was no significant difference in butyrate content between surgical colonic or fecal samples and controls; however, an alteration in the proportion of SCFAs in relation to one another was noted. These changes in the individual SCFA levels were not statistically significant. The study findings demonstrated that there were no significant differences in butyrate proportions when comparing samples from horses with surgical colic lesions to healthy control horses.

Changes in the growth performance, serum biochemistry, rumen fermentation, rumen microbiota community, and intestinal development in weaned goats during rumen-protected methionine treatment

Rumen-protected methionine (RPM) such as coated methionine (CM) and 2-hydroxy-4-(methylthio)-butanoic acid isopropyl ester (HMBi) was usually used in dairy cows, but how RPM affects meat goats remains unclear. In this study, thirty weaned male Jianzhou Da’er goats were randomly assigned to one of three treatments: fed basal diet or basal diet supplemented with 0.12% CM or 0.22% HMBi, with the aim of examining their impact on growth performance, serum biochemistry, rumen fermentation, rumen microbiota, and intestinal development in meat goats. The findings indicate that HMBi supplementation led to an increase in body weight, feed intake, and feed-to-gain ratio, whereas CM only resulted in an increase in feed intake (all p < 0.05). Both CM and HMBi resulted in an increase in serum total cholesterol (TC), blood urea nitrogen (BUN), alkaline phosphatase (ALP), and aspartate aminotransferase (AST), albeit with a decrease in serum triglycerides (TG) and β-hydroxybutyric acid (BHB, all p < 0.05). Both CM and HMBi supplementation decreased the rumen butyric acid concentration (both p < 0.05). The 16S rRNA sequencing showed that HMBi supplementation significantly increased the total abundance of Bacteroidetes and Firmicutes. Both CM and HMBi supplements increased the abundance of Rikenella and Proteiniphilum but decreased the abundance of Eisenbergiella, Enterocloster, Massilioclostridium, Eubacterium, Angelakisella, Blastopirellula, Christensenella, and Pseudoruminococcus. CM supplementation specifically increased the abundance of Desulfobulbus, Sodaliphilus, and Coprococcus while decreasing the prevalence of Anaerocella, Mogibacterium, and Collinsella. The supplementation of HMBi significantly enhanced the abundance of Paraprevotella, Bacilliculturomica, Lachnoclostridium, Dysosmobacter, Barnesiella, and Paludibacter, while decreasing the abundance of Butyrivibrio and Pirellula. Moreover, the administration of both CM and HMBi supplementation resulted in an increase in the ammonia-producing and sulfate-reducing bacteria, whereas a decrease was observed in the ammonia-oxidating, health-associated, and disease-associated bacteria. Correlational analysis revealed that TG and BHB had a positive correlation with disease-associated and ammonia-oxidating bacteria, whereas they had a negative correlation with ammonia-producing bacteria. The serum BUN, ALP, and AST were positively correlated with ammonia-producing bacteria but were negatively correlated with ammonia-oxidating bacteria. Furthermore, both CM and HMBi supplementation improve the development of the small intestine, with HMBi having a better effect. In summary, this study indicates that both CM and HMBi supplementation improve lipid metabolism, nitrogen utilization, and intestinal development. The growth promotion effect of HMBi supplementation may be attributed to the increased abundance of volatile fatty acid-producing and nitrogen-utilizing bacteria and improved intestinal development.

Inulin alleviates inflammatory response and gut barrier dysfunction via modulating microbiota in lipopolysaccharide-challenged broilers

This study was conducted to explore the protective effects of inulin against lipopolysaccharide (LPS)-induced inflammatory response and intestinal barrier dysfunction in broilers. 108 broilers were allocated to 3 treatments: 1) non-challenged broilers (Control, CON); 2) LPS-challenged broilers (LPS); 3) LPS-challenged broilers fed the basal diet supplemented with 15 g/kg of inulin (Inulin+LPS). At 21 d of age, the LPS-challenged groups received an intraperitoneal injection of LPS, and the CON group received an equal volume of saline. After 4 h of LPS exposure, samples of blood, intestinal mucosa and cecal digesta were collected. The results showed that LPS challenge induced systemic inflammation and damaged intestinal barrier function, whereas inulin attenuated LPS-induced production of pro-inflammatory cytokines by inhibiting the activation of TLR4 and NF-κB p65, and enhanced intestinal barrier function. In addition, LPS stimulation caused cecal microbial dysbiosis as shown by increased abundance of pathogenic bacteria including Ruminococcus_torques_group, Escherichia-Shigella and Subdoligranulum, while supplementation of inulin increased abundance of beneficial bacteria Faecalibacterium and Anaeroplasma, and metabolite production including propionate and butyrate concentrations. In conclusion, dietary supplementation of inulin could partially alleviate LPS-induced inflammation and intestinal barrier injury by modulating intestinal microbiota, thereby minimizing growth retardation of broilers. Our results provide a basis for the rational utilization of inulin in alleviating immune stress in broiler production.

Ferulic Acid and Clinoptilolite Affect In Vitro Rumen Fermentation Characteristics and Bacterial Abundance

This study evaluated the effects of clinoptilolite (CTL) and ferulic acid (FA) supplementation on in vitro ruminal fermentation characteristics, gas production, and bacterial abundance. Treatments were arranged in a 2 × 2 factorial design (FA: 0 or 300 ppm; CTL: 0 or 1%) with repeated measures over time (2, 4, 8, 12, 24, 36, 48, and 72 h). Throughout the incubation period, the CTL and FAZ treatments recorded the highest pH values (p ≤ 0.05), maintaining levels closest to neutrality after 72 h. After 48 and 72 h, FA and CTL decreased (p ≤ 0.05) the ammonia concentrations while increasing (p ≤ 0.05) acetate and propionate. The methane, butyrate, and iso-VFA concentrations were unaffected (p > 0.05) by any treatment. FA increased the total gas production throughout the experimental period (p ≤ 0.05). Additionally, FA and CTL significantly reduced the relative abundance of Ruminococcus albus and Streptococcus bovis (p ≤ 0.05), while no significant effects were observed for Selenomonas ruminantium (p > 0.05). These findings suggest that both additives can positively modify the rumen fermentation characteristics and microbial composition, which could significantly contribute to animal nutrition by providing a promising strategy for enhancing rumen fermentation.

Gender and age-related variations in rumen fermentation and microbiota of Qinchuan cattle.

Our study aimed to investigate the gender and age-related variations in rumen fermentation, serum metabolites, and microbiota in Qinchuan cattle. A total of 38 Qinchuan beef cattle were selected and maintained on a uniform diet for three months. Rumen fluid and blood samples were collected to determine rumen fermentation, serum metabolites, and microbial 16S rRNA sequencing. The results revealed that the concentration of rumen butyrate in female Qinchuan cattle was significantly higher than in males (P<0.05). Isobutyrate, butyrate, and isovalerate exhibited significant age-related differences. Females exhibited lower serum GLU and higher TG, NEFA levels compared to males (P<0.05). Serum ALB and UREA levels increased with age (P<0.05). Furthermore, the alpha diversity of rumen bacteria improved with age (P<0.05), with no gender differences observed. Males had higher relative abundances of Bacteroidota, Verrucomicrobiota, and Cyanobacteria, while females had higher Firmicutes and Desulfobacterota (P<0.05). The cellulose-degrading genus Ruminococcus and propionate-producing genus Succiniclasticum were more abundant in females, whereas the anti-inflammatory genus Lachnospiraceae_NK4A136_group and the hemicellulose-degrading genus Prevotella were more abundant in males (P<0.05). Age-related differences in bacteria were found in Pseudobutyrivibrio and several members of the Lachnospiraceae. Functional prediction indicated that "Amino acid metabolism" and "Lipid metabolism" were mainly enriched in females, whereas "Carbohydrate metabolism" and "Glycan biosynthesis and metabolism" were enriched in males (P<0.05). RDA analysis highlighted butyrate as a key factor influencing the rumen bacterial community. NK4A214_group and Ruminococcus were positively correlated with butyrate, while Prevotella and Pseudobutyrivibrio were negatively correlated with butyrate (P<0.05). We observed a significant improvement in the diversity and stability of rumen microbiota as age increased. Ruminococcus, NK4A214_group, and Prevotella were likely contributors to variations in energy utilization and fat deposition between male and female Qinchuan cattle.

Iron (Magnetite) Nanoparticle-Assisted Dark Fermentation Process for Continuous Hydrogen Production from Rice Straw Hydrolysate

The use of metal nanoparticles (NPs) to enhance hydrogen production in dark fermentation (DF) has become a pioneering field of interest. In particular, iron-based nanoparticles (FeNPs) play a pivotal role in enhancing the activity of metalloenzymes and optimizing feedstock utilization, resulting in improved hydrogen production. This study investigated the effect of FeNPs (magnetite) supplementation at three different concentrations of 50, 100, and 200 ppm in a continuous dark fermenter for the production of hydrogen from rice straw acid hydrolysate. The highest hydrogen production rate of 2.6 ± 0.3 NL H2/L-d was achieved with the addition of 100 ppm of nanoparticles, representing a 53% increase compared to the condition without FeNPs addition. This improvement was driven by a microbial community in which Clostridium was the major dominant genus. In addition, increasing the nanoparticle concentration to 100 ppm resulted in an increase in butyrate concentration to 2.0 ± 0.1 g/L, which is 43% higher than the butyrate concentration without FeNPs. However, when the NP concentration was increased to 200 ppm, the hydrogen production rate decreased to 1.6 ± 0.2 NL H2/L-d. This study can serve as a guideline for future research aimed at evaluating the effects of FeNPs in continuous dark fermentation systems. This work highlights the potential benefits and challenges associated with the use of FeNPs, paving the way for future studies to optimize their application and improve the efficiency of dark fermentation processes.

Xylanase enhances gut microbiota-derived butyrate to exert immune-protective effects in a histone deacetylase-dependent manner

BackgroundCommensal bacteria in the intestine release enzymes to degrade and ferment dietary components, producing beneficial metabolites. However, the regulatory effects of microbial-derived enzymes on the intestinal microbiota composition and the influence on host health remain elusive. Xylanase can degrade xylan into oligosaccharides, showing wide application in feed industry.ResultsTo validate the immune-protective effects of xylanase, Nile tilapia was used as the model and fed with xylanase. The results showed that dietary xylanase improved the survival rate of Nile tilapia when they were challenged with Aeromonas hydrophila. The transcriptome analysis showed significant enrichment of genes related to interleukin-17d (il-17d) signaling pathway in the xylanase treatment group. High-throughput sequencing revealed that dietary xylanase altered the composition of the intestinal microbiota and directly promoted the proliferation of Allobaculum stercoricanis which could produce butyrate in vitro. Consequently, dietary xylanase supplementation increased the butyrate level in fish gut. Further experiment verified that butyrate supplementation enhanced the expression of il-17d and regenerating islet-derived 3 gamma (reg3g) in the gut. The knockdown experiment of il-17d confirmed that il-17d is necessary for butyrate to protect Nile tilapia from pathogen resistance. Flow cytometry analysis indicated that butyrate increased the abundance of IL-17D+ intestinal epithelial cells in fish. Mechanistically, butyrate functions as an HDAC3 inhibitor, enhancing il-17d expression and playing a crucial role in pathogen resistance.ConclusionDietary xylanase significantly altered the composition of intestinal microbiota and increased the content of butyrate in the intestine. Butyrate activated the transcription of il-17d in intestinal epithelial cells by inhibiting histone deacetylase 3, thereby protecting the Nile tilapia from pathogen infection. This study elucidated how microbial-derived xylanase regulates host immune function, providing a theoretical basis for the development and application of functional enzymes.7BVRPuQYn3eQdwFeU5j8vPVideo

Effects of chicken slurry inclusion on apparent total tract macronutrient digestibility, palatability, and fecal characteristics, microbiota, and metabolites of healthy adult dogs.

"Premium" pet foods are often formulated with meat slurries. Meat slurries are believed to be of higher quality than rendered meals, but inadequate research has been performed to test how their inclusion affects palatability, digestibility, or indicators of gastrointestinal health. Therefore, the objectives of this study were to determine how chicken slurry inclusion affected the palatability and apparent total tract macronutrient digestibility (ATTD) of dog foods and to assess their effects on the fecal characteristics, metabolites, and microbiota of dogs. A replicated 3x3 Latin square design digestibility study was conducted using 9 healthy adult dogs (age = 5.44 ± 0.53 yr) to test diets containing 0% (control; CON), 8% (low inclusion; LOW), and 16% (high inclusion; HIGH) chicken slurry. The experiment comprised three 21-day experimental periods (14 days of adaptation, 5 days of total fecal collection (used for ATTD calculations), and 2 days of blood collection). On the first day of fecal collections, one fresh sample was collected for measurement of pH, dry matter (DM) content, fermentative metabolite concentrations, and microbiota populations. A 2-day palatability study (n=20 dogs) was also conducted to compare CON vs. HIGH. Data were analyzed statistically by Mixed Models using SAS 9.4, with P<0.05 being significant. In the palatability study, dogs were shown to prefer (P<0.05) the HIGH diet by a ratio of 2:1. In the digestibility study, fecal output, scores, pH, and DM percentage were not different among diets. The ATTD of protein was higher (P<0.05) for the HIGH diet (84.6%) than for the LOW (82.7%) or CON (82.6%) diets. The ATTD of other nutrients and energy were not different among diets (all over 80%). Fecal propionate, butyrate, and total short-chain fatty acid concentrations were higher (P<0.05) in dogs fed the LOW diet (122.0, 67.4, and 408.2 βmol/g, respectively) than those fed the HIGH diet (89.0, 46.9, and 338.2 βmol/g, respectively). The other fecal metabolites (acetate, branched-chain fatty acids, ammonia, phenol, and indole) were not different among treatments. Few changes to the fecal microbiota were noted. However, the relative abundance of fecal Fusobacterium was higher (P<0.05) in dogs fed the CON diet than those fed the HIGH diet (25.% vs. 20.0% relative abundance). In summary, chicken slurry inclusion improved palatability but had minimal effects on nutrient digestibility and fecal characteristics, metabolites, and microbiota.

Effect of Dietary Supplementation with Different Proportions of Amaranthus hypochondriacus Stem and Leaf Powder on Intestinal Digestive Enzyme Activities, Volatile Fatty Acids and Microbiota of Broiler Chickens

Amaranthus hypochondriacus is rich in nutrients and represents a feed resource with significant potential. This experiment aimed to study the effects of different proportions of Amaranthus hypochondriacus stem and leaf powder (AHSL) on intestinal digestive enzyme activities, cecal volatile fatty acids, and the microbiota of broilers. A total of 288 one-day-old male broilers (Ross 308) were randomly assigned to the control diet group and the 3%, 6%, and 9% AHSL diet group for days 0–21. Subsequently, the 3%, 6%, and 9% AHSL diets were switched to 5%, 10%, and 15% AHSL diets for days 22–42. The results demonstrated that the dietary inclusion of AHSL significantly affected sucrase activity in the jejunal mucosa (p &lt; 0.05). The 5% AHSL group exhibited the highest sucrase activity, followed by the control group, both of which showed significantly higher activity compared to the 10% and 15% AHSL groups (p &lt; 0.05). The cecal pH in the 5%, 10%, and 15% AHSL groups was significantly lower than that in the control group (p &lt; 0.05). The contents of acetate, propionate, butyrate, and valerate in the cecum of the 10% and 15% AHSL groups were significantly higher than those of the control group (p &lt; 0.05). The addition of AHSL had no significant effect on the alpha diversity of cecum microorganisms. The relative abundance of Ruminococcaceae_UCG_005 and Lactonifactor was significantly higher in the 10% AHSL group compared to the control group, whereas the 15% AHSL group had a significantly higher relative abundance of Clostridium_sensus_tricto12, Peptoclostridium, Anaerofilum, and Peptococcaceae. In summary, the inclusion of 5% AHSL in the diet enhances sucrase activity in the jejunum of broilers, while 10% or 15% AHSL increases the volatile fatty acid content and reduces the pH value in the cecum, without adverse effects on the cecal microbiota.

Dynamic changes in microbiota and volatile profiles of Marselan wine by single or pairwise inoculated three indigenous non-Saccharomyces yeasts

The object of this study was to compare the effects of three indigenous non-Saccharomyces cerevisiae strains (Hanseniaspora uvarum, Metschnikowia sinensis and Rhodotorula mucilaginosa) and their paired (co-inoculated) fermentation on the microbial communities and volatile profiles during the fermentation of Marselan wine. Results showed that both monoculture and mixed fermentation with non-Saccharomyces strain can complete alcohol fermentation wherein the alcohol content of indigenous yeast treatments were significantly higher than that of control NSD. A total of 44 aroma compounds were identified in all samples, among which the H + R mixed inoculation showed the highest aroma content (28581±1576.61 μg/L). In particular, the contents of ethyl butyrate (V5), ethyl octanoate (V9), and ethyl decanoate (V11) were significantly high, which could enhance the fresh fruit aroma in Marselan wine. Microbial diversity analysis showed that the diversity of fungi between groups was greater than that of bacteria, and H + R (Hanseniaspora and Rhodotorula) had higher microbial abundance (bacteria 79, fungi 78) than the other groups. Spearman correlation analysis revealed that Fructobacillus, Acinetobacter, and other indigenous microorganisms were positively correlated with volatile substances. In summary, the mixed fermentation of Hanseniaspora and Rhodotorula can be considered an effective strategy for improving the aroma quality of Marselan wine. This study provides new insight and useful references for the role and application of native non-Saccharomyces yeast in wine making.

Hydrophobic interaction-induced self-assembly of V-type lotus starch with butyric acid into stable structures: Regulation by butyric acid concentration

V-amylose is a modified helical structure capable of interacting with butyric acid (BA), which typically shows limited affinity for native amylose. The encapsulation of BA within V-amylose enhances its enzymatic resistance while facilitating the delivery of BA to the gut, where it can exert beneficial health effects. Consequently, enhancing the incorporation of BA into starch-based food is a crucial strategy for achieving these objectives. The concentration of guest BA plays a critical role in the hydrophobic interaction-induced complexation with V-amylose, and understanding the structural changes involved in this process is essential for the design of optimal products. In this study, V-amylose derived from high-amylose lotus starch was utilized to form complexes with BA. The structure and in vitro digestibility of the complexes formed at varying BA concentrations were investigated. The results demonstrate that higher BA concentrations weakened the hydrophobic interactions in the V-amylose system. Nevertheless, the highest complex index (i.e., 11.7 g/100 g) of V-amylose was attained at a 50 % BA concentration, indicating a balance between BA-regulated hydrophobic aggregation and the density of BA during complexation. These V-amylose complexes produced with elevated BA content exhibited high crystallinity and molecular order, along with enhanced thermal stability and resistance to enzymolysis. These findings support the feasibility of loading BA into V-amylose and provide valuable insights into the hydrophobic complexation regulated by BA concentration.

The effect of supplemental arginine on the gut microbial homeostasis of broilers during sub-clinical necrotic enteritis challenge.

Necrotic enteritis (NE) is an enteric disease of poultry that alters the structure of the gut microbial community causing dysbiosis. This 28day experiment investigated the effects of 125% and 135% arginine diets on the gut microbial diversity and composition of broilers during a subclinical NE challenge. One hundred and twenty one-day-old chicks were randomly allocated to 4 treatments with six replicates each- Uninfected + Basal, NE + Basal, NE + Arg 125%, and NE + Arg 135% diet groups. NE was induced by inoculating 1 × 104E. maxima sporulated oocysts on day 14 and 1 × 108CFUC. perfringens on days 19, 20, and 21 of age. The NE challenge significantly decreased the number of observed amplicon sequence variants (p = 0.03), the abundance of the phylum Firmicutes (p < 0.01), and the species Mediterraneibacter cottocaccae (p = 0.01) in the ceca of birds on day 21. The NE challenge significantly increased the Bray-Curtis index (p < 0.01), and the abundance of the phylum Bacteroidota (p < 0.01), family Odoribacteraceae (p < 0.01), genus Odoribacter (p < 0.01), and species O. splanchnicus (p = 0.01) on day 21. During NE, the 125% arginine diet restored the abundance of the phylum Bacteroidota (p = 0.03), family Odoribacteraceae (p = 0.03) and Oscillospiraceae (p = 0.03), genus Odoribacter (p = 0.03), and species O. splanchnicus (p = 0.03) and M. cottocaccae (p < 0.01) on day 21. The 135% arginine diet effectively restored the loss in alpha diversity (p = 0.01) caused by NE, the abundance of the phylum Firmicutes (p = 0.01) and Bacteroidota (p < 0.01), family Oscillospiraceae (p = 0.03) and Odoribacteraceae (p < 0.01), genus Odoribacter (p < 0.01), and species O. splanchnicus (p < 0.01) and M. cottocaccae (p < 0.01) on day 21. On day 28, the treatments had a significant effect on the cecal propionate (p = 0.01), butyrate (p = 0.04), and total SCFA (p = 0.04) concentrations. In conclusion, the 125% and 135% arginine diets restored gut microbial composition during a subclinical NE challenge, but not the cecal SCFA profile. Hence, arginine in combination with other feed additives could be used in restoring gut microbial homeostasis during NE in poultry.

Effects of Supplementing Different Quantities of Moringa stenopetala Leaves on Plasma Metabolite and Acylcarnitine Profile, Body Condition Score and Milk Yield Performance in Zebu (Bos indicus) Cattle.

The formulation of multi-nutrient blocks based on low-cost and locally available browse feed resources can be a valid feeding strategy in Sub-Saharan Africa, where inadequate feed supply, both in quality and quantity, is a major constraint. We evaluated the four different inclusion percentages (M-0%, M-25%, M-35% and M-45%) of Moringa stenopetala leaf powder to multi-nutrient blocks on their change on blood metabolite of dairy cows under practical, ranging conditions. Multi-nutrient blocks with four inclusion rates of M. stenopetala leaves were applied as complementary feed for free ranging dairy cows. The study was performed on 24 free ranging dairy cows reared around Arba Minch town in the Southern Ethiopian Rift Valley. Blood samples were collected from the jugular vein of dairy cows both before and after supplementation. Plasma glucose, beta hydroxy butyrate (BHB), urea, creatinine, triglycerides and nonesterified fatty acids (NEFA) concentration was quantified spectrophotometrically. Dried serum spots were subject to quantitative electrospray tandem mass spectrometry to estimate changes in nutrient metabolism based on selected carnitines. Based on these measurements, the milk yield and body condition score were increased during the period of multi-nutrient block supplementation. During the supplementation period, the cows got higher plasma glucose, triglyceride and urea concentrations and lower concentrations of BHB, NEFA and creatinine. From the metabolite profiles, a more efficient nutrient use could be concluded. Although no clear dose-response relationship was observed, the highest inclusion of the M. stenopetala leaves in the multi-nutrient blocks gave the best performance. This outcome supports the idea of implementing M. stenopetala based multi-nutrient blocks on tropical smallholder farms that are not easily accessible to conventional extension services.

Comparing the Impact of Continuous Endurance and High-intensity Interval Training on Cecal Butyrate and Propionate Levels in Diabetic Rats Induced by High-fat Diet

Background: Dysbiosis and metabolic disorders of the microbiota, often caused by an imbalance in the intestinal microbial composition, are significant issues linked to immobility, obesity, and diabetes. Physical exercise is recognized for its role in managing these symptoms by regulating the composition and metabolites of the intestinal microbiota, thereby improving gut health and overall metabolic function. Objectives: This study aimed to investigate and compare the effects of continuous endurance training (CET) and high-intensity interval training (HIIT) on two key cecal microbiota metabolites, butyrate and propionate, in diabetic rats. Methods: Forty-five male Wistar rats were made diabetic by a high-fat diet and were trained under CET and HIIT exercise protocols. Cecal tissue samples were taken from the rats to evaluate the effect of exercise, and the levels of two microbial metabolites, butyrate and propionate, were measured using the high-performance liquid chromatography (HPLC) method. Results: Among the exercise patterns studied, HIIT significantly improved the concentrations of butyrate and propionate, while CET showed no effect on these metabolites. Conclusions: Our findings suggest that, unlike CET, HIIT may effectively mitigate metabolic disturbances resulting from gut dysbiosis in diabetic patients. However, any definitive conclusion about the effects of CET and HIIT exercises on intestinal microbial metabolites necessitates further comprehensive tests on other metabolites and an examination of additional supporting evidence, such as changes in the composition of the intestinal microbiome.

The Link between Salivary Amylase Activity, Overweight, and Glucose Homeostasis.

Butyrate, a short-chain fatty acid (SCFA) produced by the fermentation of dietary fibers in the colon, plays a pivotal role in regulating metabolic health, particularly by enhancing insulin sensitivity. Given the rising incidence of metabolic disorders, understanding the factors that influence butyrate production is of significant interest. This study explores the link between salivary amylase activity and butyrate levels in overweight women of reproductive age. Participants were categorized into low (LSA) and high (HSA) salivary amylase activity groups and further divided into two subgroups: one followed a low-starch diet (LS), and the other underwent caloric restriction (CR). We assessed salivary amylase activity and measured serum butyrate concentrations to examine their associations. Our findings showed a significant, though weak, positive correlation (ρ = 0.0486, p < 0.05), suggesting a link between salivary amylase activity and butyrate levels. The statistical significance, despite the weak correlation, implies that this relationship is not random. Moreover, higher baseline butyrate levels were observed in women with elevated salivary amylase activity. Also, women with low salivary amylase activity on a low-starch diet experienced a more pronounced increase in butyrate levels compared to those on caloric restriction. These results suggest that salivary amylase activity and dietary intake interact to influence butyrate production, with potential implications for improving insulin sensitivity and metabolic health. The study underscores the potential of butyrate in enhancing insulin sensitivity and promoting overall metabolic well-being. Further research is necessary to clarify the mechanisms involved and to understand the long-term effects of butyrate on metabolic health across different populations.

483 DMI, gastrointestinal tract fermentation and permeability, and white blood cell responses in beef heifers provided post-ruminal yeast cell wall extract following feed restriction

Abstract The objectives of this study were to 1) evaluate gastrointestinal fermentation characteristics and permeability, and white blood cell concentrations as beef heifers recovered from a feed restriction (FR) challenge, and 2) determine whether post-ruminal provision of a yeast cell wall extract (YCW) modulated responses. Ruminally cannulated beef heifers (n = 8) were used in a 2 × 2 crossover design. Treatments (TRT) included an abomasal infusion of a placebo (PLC; maltodextrin) or YCW derived from Saccharomyces cerevisiae (2 g/dose) infused at 0600 and 1800 h. Heifers were subject to 5-d of FR (offering 30% of ad libitum DMI) followed by five 5-d recovery phases (REC1, REC2, REC3, REC4, and REC5). Daily DMI, and rumen, fecal, and blood samples were collected on d 5 of FR, REC1, REC3, and REC5 with an additional collection on d 2 of REC1. Total gastrointestinal and post-ruminal permeability were measured using a ruminal dose of Cr-EDTA and an abomasal dose of Co-EDTA, respectively, during FR, REC1, REC3, and REC5 with concurrent urine collection. Data were analyzed to determine the effects of YCW provision, day, and the 2-way interaction. There were no TRT or TRT×day effects for any variables except DMI (interaction, P = 0.04), where DMI did not differ during the FR challenge; however, heifers provided YCW had a greater increase by REC1 compared with PLC heifers without any means differing. DMI progressively increased from FR, to REC1, REC2, and REC5. Ruminal acetate concentration increased (P &amp;lt; 0.01) from FR (45.4 mmol/L) to REC1 d5 (60.1 mmol/L) and increased further to REC3 (67.3 mmol/L) with no change thereafter (68.3 mmol/L in REC5). Ruminal propionate concentration increased (P &amp;lt; 0.01) from FR (14.5 mmol/L) to REC1 d2 (27.7 mmol/L) and was not different thereafter. Similarly, butyrate concentration increased (P &amp;lt; 0.01) from FR (7.9 mmol/L) to REC1 (d 5; 15.0 mmol/L) and was not different thereafter. Fecal acetate, propionate, and butyrate concentrations were not affected by day (P ≥ 0.12). Total gastrointestinal and post-ruminal permeability were greatest during FR (P &amp;lt; 0.01; 2.6% and 2.2% of the infused marker was excreted in urine, respectively) and decreased to 1.6% and 1.1%, respectively, in REC3 followed by an increase in REC5 for total (2.0% of infused) but not post-ruminal (1.0% of infused) permeability. The concentration of neutrophils (P &amp;lt; 0.01) was greatest on REC1 d2 (4.84 ×106 μmol/mL) and eosinophil concentration (P &amp;lt; 0.01) was greatest during FR (0.53 ×106 μmol/mL), least on d 2 of REC1 and increased on d 5 of REC1 but was not different thereafter. WBC (P &amp;lt; 0.01) gradually decreased (P = 0.02) from FR and REC1 d2 to REC3 and REC5. Post-ruminal provision of YCW may accelerate increases in DMI early in the recovery from FR, yet treatment did not modulate ruminal or fecal SCFA, blood concentrations, or gastrointestinal permeability.

33 Beyond bacteria: Impact of live yeast as a probiotic on the intestinal health of dogs

Abstract Inactivated yeast and yeast-based products are commonly used in pet food to improve palatability, contribute to dietary protein content, and improve gastrointestinal functionality. However, the use of viable yeast Saccharomyces as a probiotic may contribute to additional beneficial effects on dogs and cats. Considering that, in this presentation, we will focus on the use of viable yeast as a probiotic for dogs. A study conducted at the Federal University of Parana, Brazil, observed that Beagle dogs supplemented with a probiotic yeast presented reduced fecal concentrations of total biogenic amines, ammonia, and aromatic compounds and greater fecal concentrations of butyrate. The supplemented dogs also presented an improvement in dysbiosis index, a greater abundance of Bifidobacterium and Turicibacter, and a reduced abundance of Escherichia coli in feces. In addition, control group dogs presented upregulation in microbial genes related to virulence factors (such as lipopolysaccharide export system), antibiotic resistance, and osmotic stress, compared with the probiotic group. These results may indicate a possible protective effect of the yeast probiotic against potential pathogenic bacteria in the gut. The mechanisms by which yeast probiotics may contribute to gastrointestinal functionality in dogs and cats are not fully elucidated. However, they are usually attributed to the stimulation of brush edge disaccharidases; competition for adhesion sites against potential pathogens; stimulation of nonspecific immunity; neutralization of toxins; and direct effect against potentially pathogenic microorganisms. Many of these mechanisms are influenced directly by yeast cell wall components, such as mannans and beta-glucans. One of the main mechanisms of action of mannans is the elimination of bacteria with pathogenic potential that present type-1 fimbriae, such as some strains of E. coli and Salmonella, preventing their adhesion and colonization to the host mucosa. This may also contribute to the establishment of beneficial bacteria in the gut. We can conclude that viable yeast Saccharomyces as a probiotic may have promising beneficial effects on intestinal functionality of dogs.

Effects of 5-Aminolevulinic Acid Supplementation on Gas Production, Fermentation Characteristics, and Bacterial Community Profiles In Vitro.

To investigate the effect of 5-aminolevulinic acid (5-ALA) on in vitro rumen gas production, fermentation characteristics, and bacterial community profiles, five levels of 5-ALA (0, 100, 500, 1000, and 5000 mg/kg DM) were supplemented into a total mixed ration (concentrate/forage = 40:60) as substrate in an in vitro experiment. Results showed that as the supplementation level of 5-ALA increased, asymptotic gas production (b) decreased linearly and quadratically (p < 0.01) while the dry matter degradation rate increased quadratically (p < 0.01). Meanwhile, the propionate concentration of 72 h incubation fluid increased linearly (p = 0.03) and pH value increased linearly and quadratically (p < 0.01), while the concentrations of butyrate, isobutyrate, valerate, isovalerate, and NH3-N and the ratio of acetate/propionate (A/P) decreased linearly and quadratically (p < 0.05). There was no significant difference in any alpha diversity indices of bacterial communities among the various 5-ALA levels (p < 0.05). PCoA and PERMANOVA analysis revealed that the bacterial profiles showed a statistical difference between the treatment 5-ALA at 1000 mg/kg DM and the other levels except for 5000 mg/kg DM (p < 0.05). Taxonomic classification revealed a total of 18 and 173 bacterial taxa at the phylum and genus level with relative abundances higher than 0.01% in at least half of the samples, respectively. LEfse analysis revealed that 19 bacterial taxa were affected by 5-ALA levels. Correlation analysis showed that Actinobacteriota was positively correlated with the gas production parameter b, the ratio of A/P, and the concentration of butyrate, isovalerate, and NH3-N (p < 0.05) and negatively correlated with pH (p < 0.05). WPS-2 exhibited a negative correlation with the gas production parameter b, the ratio of A/P, and the concentration of butyrate, valerate, isobutyrate, isovalerate, and NH3-N (p < 0.05), along with a weaker positive correlation with pH (p = 0.04). The Bacteroidales BS11 gut group was negatively correlated with the concentration of propionate but positively correlated with gas production parameter b and the concentration of butyrate and NH3-N (p < 0.05). The Lachnospiraceae NK3A20 group was found to have a positive correlation with gas production parameter b, the ratio of A/P, and the concentration of butyrate, isobutyrate, isovalerate, valerate, total VFA, and NH3-N (p < 0.05), but a highly negative correlation with pH (p < 0.01). Differential metabolic pathways analysis suggested that metabolic pathways related to crude protein utilization, such as L-glutamate degradation VIII (to propanoate), L-tryptophan degradation IX, and urea cycle, increased with 5-ALA levels. In summary, including 5-ALA in the diet might improve energy and protein utilization by reducing the abundance of Actinobacteriota, the Bacteroidales BS11 gut group, the Lachnospiraceae NK3A20 group, and certain pathogenic bacteria and increasing the abundance of WPS-2.

The optimization and validation of a gas chromatography-mass spectrometry method to analyze the concentration of acetate, propionate and butyrate in human plasma or serum

Fermentation-derived short-chain fatty acids (SCFA)44SCFA: short-chain fatty acids. are potential mediators of the health benefits associated with dietary fiber intake. SCFA affect physiological processes locally in the gut and on distant organs via the systemic circulation. Since SCFA are used as energy source for colonocytes and substrate for the liver metabolism, their concentrations in the systemic circulation are low. Therefore, quantification of systemic SCFA requires sensitive analytical techniques. This article covers the optimization and validation of a gas chromatography-mass spectrometry method to measure systemic SCFA concentrations following derivatization with 2,4-difluoroaniline (DFA)55DFA: 2,4-difluoroaniline. and extraction in ethyl acetate. Sample preparation was optimized by varying the amount of DFA, coupling agent 1,3-dicyclohexylcarbodiimide, ethyl acetate and sodium bicarbonate, which is used to quench derivatization. In addition, evaporation of the samples using a vacuum concentrator resulted in less contamination, notably of acetate, compared to drying with N2 gas. The method showed excellent linearity with coefficient of variation (R2) > 0.99 and a good precision (relative standard deviation < 20 %) and accuracy. Finally, systemic concentrations of SCFA in human plasma samples could successfully be determined.