Lactobacillus acidophilus and Bacillus subtilis significantly change the growth performance, serum immunity and cecal microbiota of Cherry Valley ducks during the fattening period.

This study explored the effects of a Bacillus subtilis and Lactobacillus acidophilus mixture containing the co-fermented products of the two probiotics on growth performance, serum immunity and cecal microbiota of Cherry Valley ducks. This study included 480 one-day-old Cherry Valley ducks divided into four feeding groups: basal diet (control group) and basal diet supplemented with 300, 500, or 700 mg/kg of the probiotic powder; the ducks were raised for 42 days. Compared with the control group, body weight on day 42 and the average daily gain on days 15-42 significantly increased (p < 0.05), and the feed conversion rate significantly decreased (p < 0.05) in the experimental groups. Furthermore, the serum immunoglobulin (Ig) A, IgG, IgM, and interleukin (IL)-4 levels increased significantly (p < 0.05), and IL-1ß, IL-2, and tumor necrosis factor-α decreased significantly (p < 0.05) in the experimental groups. Finally, Sellimonas, Prevotellaceae NK3B31 group, Lachnospiraceae NK4A136 group and Butyricoccus played an important role in the cecal microbiota of the experimental group. Thus, the probiotic powder has impacts on the growth performance, serum immunity and cecal microbiota of Cherry Valley Ducks.

A type 4 resistant potato starch alters the cecal microbiome and gene expression in mice fed a western diet based on NHANES data.

Four major types of resistant starch (RS1-4) are present in foods, all of which can alter the microbiome and are fermented in the cecum and colon to produce short-chain fatty acids (SCFAs). Type 4 RSs are chemically modified starches, not normally found in foods, but have become a popular food additive as their addition increases fiber content. Multiple studies, in humans and rodents, have explored how different RS4 affect post-prandial glucose metabolism, but fewer studies have examined the effects of RS4 consumption on the microbiome. In addition, many RS studies conducted in rodents use high-fat diets that do not approximate what is typically consumed by humans. To address this, mice were fed a Total Western Diet (TWD), based on National Health and Nutrition Examination Survey (NHANES) data that mimics the macro and micronutrient composition of a typical American diet, for six weeks, and then supplemented with 0, 2, 5, or 10% of the RS4, Versafibe 1490™ (VF), a phosphorylated and cross-linked potato starch, for an additional three weeks. The cecal contents were analyzed for SCFA content and microbiota composition. Butyrate production was increased while branched chain SCFA production decreased. The alpha-diversity of the microbiome decreased in mice fed the TWD with 10% VF 1490 added while the beta-diversity plot showed that the 5% and 10% VF groups were distinct from mice fed the TWD. Similarly, the largest changes in relative abundance of various genera were greatest in mice fed the 10% VF diet. To examine the effect of VF consumption on tissue gene expression, cecal and distal colon tissue mRNA abundance were analyzed by RNASeq. Gene expression changes were more prevalent in the cecum than the colon and in mice fed the 10% VF diet, but the number of changes was substantially lower than we previously observed in mice fed the TWD supplemented with native potato starch (RPS). These results provide additional evidence that the structure of the RS is a major factor determining its effects on the microbiome and gene expression in the cecum and colon.

Effects of different supplemental levels of protease DE200 on the production performance, egg quality, and cecum microflora of laying hens.

This study aimed to investigate the effects of different levels of the protease DE200 on the performance, egg quality, organ index, and cecum microflora of Hy-line W36 laying hens. In this experiment, a total of 180 laying hens aged 300 d were randomly divided into three treatment groups and fed diets containing 0, 100, or 200 g/t DE200. The experimental period was 8 wk, including 2 wk of prefeeding and 6 wk of the formal experiment. Regular feeding was performed thrice a day and eggs were collected twice daily, and the feed intake and the egg quality were recorded. The results showed that in terms of production performance, dietary supplementation with different levels of DE200 significantly increased egg production (EP; P < 0.05) and significantly decreased the feed conversion ratio (FCR; P < 0.05) and average daily feed intake (ADFI; P < 0.05) without affecting egg weight (EW). In addition, the addition of DE200 significantly reduced the egg breakage rate (P < 0.05) and tended to increase the Haugh unit and decrease the water content of the yolk (P > 0.05). In the cecal microflora, the addition of DE200 increased the proportions of Bacteroidetes and Firmicutes at the phylum level while reducing the proportion of Fusobacteria. Furthermore, at the genus level, the addition of DE200 increased the proportions of Bacteroides and Faecalibacterium and reduced the proportion of Megamonas. This study suggested that the protease DE200 can be used as a feed supplement to improve the production performance of laying hens.

In the production of laying hens, improving the efficiency of dietary protein utilization is important. The aim of this study was to investigate the effects of the protease DE200 on the performance, egg quality and cecal microflora of Hyline white laying hens. A total of 180 laying hens aged 300 d were randomly divided into three treatment groups and fed diets containing 0, 100, or 200 g/t DE200 for 56 d. The results showed that supplementation with 100 or 200 g/t DE200 in the basal diet improved the production performance and egg quality of laying hens. DE200 (100 g/t) improved the balance of the cecal microflora, and DE200 (200 g/t) increased the richness and diversity of the cecal microflora of laying hens. Dietary supplementation with DE200 can improve the intestinal health and nutrient utilization efficiency of laying hens by improving the intestinal flora.

Does the dietary supplementation of organic nano-zinc as a growth promoter impact broiler's growth, carcass and meat quality traits, blood metabolites and cecal microbiota?

The present investigation aimed to examine the impact of different dietary organic zinc nanoparticle (ZnNP) levels on gut bacteria, meat quality, growth performance, carcass traits, and blood indicators of broilers. A total of 180 unsexed one-wk broiler chicks (Cobb) were allotted to 3 experimental groups and received a basal diet supplemented with 0, 0.2, and 0.4 mg ZnNPs/Kg diet, respectively. The results showed that, after 38 d of age, the supplementary ZnNPs at a level of 0.4 mg/kg raised body weight and weight gain compared to the control and 0.2 mg ZnNPs/kg diet. The addition of ZnNPs improved the daily feed intake. Some of the carcass characteristics in ZnNPs groups excelled that of the control. ZnNPs treatments gave higher dressing % and decreased (P < 0.05) the cholesterol rates, LDL, and uric acid in the blood. In addition, it gave the best concentrations of ALT and AST. The ZnNPs groups exhibited substantially (P < 0.05) improved moisture and fat values in meat samples. The group given ZnNPs at a concentration of 0.4 mg/kg had a substantially (P < 0.05) lower count of TYMC and E. coli. In conclusion, the high level of ZnNPs (0.4 mg/kg) improved the broilers' performance and some of their carcass traits, enhancing their health and meat quality.

Impacts of willow (Salix babylonica L.) leaf extract on growth, cecal microbial population, and blood biochemical parameters of broilers.

The investigation examined the use of willow leaf extract (WLE) on broiler chickens, examining carcass characteristics, cecal microbiota, antioxidants, and blood parameters. In 4 groups of 300 chicks, a basal diet was given for 5 wk, and the first treatment was basal diet (C). The diets for the remaining 3 treatments (WLE150, WLE300, and WLE450) contained 150, 300, and 450 mg of willow leaf extract /kg, respectively. The study found that birds fed willow leaf extract supplements had significantly greater body weight (BW), body weight gain (BWG), and enhanced feed conversion ratio (FCR) vs. the control group. Birds fed at 450 mg/kg food showed the greatest growth features, carcass weight, liver weight, lower abdominal fat, better low-density lipoprotein (LDL), and high-density lipoprotein (HDL) concentrations, and highest hematological characteristics. Chickens fed diets supplemented with varied doses of willow leaf extract showed significantly increased antioxidant enzyme activity, with higher amounts of glutathione peroxidase (GPx) activity, superoxide dismutase (SOD), total antioxidant capacity (TAC), and lower malondialdehyde (MDA). However, in the study, birds fed a diet supplemented with 450 mg of willow leaf extract per kg meal showed a significant drop of 13.02%, which found no significant variations in hazardous bacteria (Escherichia coli) across 2 treatments (WLE150 and WLE300). In addition, the study discovered that birds fed with varied doses of willow leaf extract had fewer cecum infections (Staphylococci aureus). We conclude that using willow at a level of 450 mg/kg diet can significantly enhance the BWG, FCR, antioxidant levels and beneficial bacteria activity besides the condition of broiler chicken's general health.

Effects of grape seed procyanidins on antioxidant function, barrier function, microbial community, and metabolites of cecum in geese.

The gut is the first line of defense for body health and is essential to the overall health of geese. Grape seed procyanidins (GSPs) are proverbial for their antioxidant, anti-inflammatory, and microflora-regulating capabilities. This study aimed to inquire into the influences of dietary GSPs on the intestinal antioxidant function, barrier function, microflora, and metabolites of geese based on 16S rRNA sequencing and metabolomics. In total, 240 twenty-one-day-old Sichuan white geese were randomly divided into 4 groups, each of which was supplied with 1 of 4 diets: basal diet or a basal diet supplemented with 50, 100, or 150 mg/kg GSPs. Diets supplemented with GSPs at different concentrations significantly increased the total antioxidant capacity and superoxide dismutase activity in cecal mucosa (P < 0.001). Dietary supplementation with 50 or 100 mg/kg GSPs significantly increased catalase activity (P < 0.001). The serum diamine oxidase, D-lactic acid, and endotoxin concentrations were decreased by GSP supplementation in the goose diet. Dietary GSP supplementation increased microbial richness and diversity, enhanced the relative abundance of Firmicutes, and decreased that of Bacteroidetes in the cecum. Diets supplemented with 50 or 100 mg/kg GSPs enriched Eubacterium coprostanoligenes and Faecalibacterium. Dietary GSPs substantially raised the acetic and propionic acid concentrations in the cecum. The butyric acid concentration increased when the GSP dosage was 50 or 100 mg/kg. Additionally, dietary GSPs increased the levels of metabolites that belong to lipids and lipid-like molecules or organic acids and derivatives. Dietary GSP supplementation at 100 or 150 mg/kg reduced the levels of spermine (a source of cytotoxic metabolites) and N-acetylputrescine, which promotes in-vivo inflammation. In conclusion, dietary supplementation with GSPs was beneficial to gut health in geese. Dietary GSPs improved antioxidant activity; protected intestinal barrier integrity; increased the abundance and diversity of cecal microflora; promoted the proliferation of some beneficial bacteria; increased the production of acetic, propionic, and butyric acids in the cecum; and downregulated metabolites associated with cytotoxicity and inflammation. These results offer a strategy for promoting intestinal health in farmed geese.

Combined effect of metabolites produced by a modified Lactobacillus casei and berry phenolic extract on Campylobacter and microbiome in chicken cecum contents.

Campylobacter is one of the most common foodborne bacterial pathogens causing illness, known as campylobacteriosis, in the United States. More than 70% of the campylobacteriosis cases have direct or indirect relation with poultry/poultry products. Currently, both conventional and organic/pasture poultry farmers are searching for sustainable alternative to antibiotics which can reduce colonization and cross-contamination of poultry products with Campylobacter and promote poultry health and growth. Probiotic and their nutritional supplement, known as prebiotic, have become consumers' preferences as alternatives to antibiotics/chemicals. In this study, we evaluated the combined effect of plant-derived prebiotic and probiotic-derived metabolites in reducing growth of Campylobacter in cecum contents, a simulated chicken gut condition. Cecum contents were collected from chickens pre-inoculated with kanamycin-resistant Campylobacter (CJRMKm), were incubated over 48 h time period, while being supplemented with either berry phenolic extract (BPE), cell free cultural supernatant from an engineered probiotic, Lactobacillus casei, or their combination. It was found that combine treatments were able to reduce both inoculated and naturally colonized Campylobacter more effectively. Microbiome analysis using 16S rRNA sequencing also revealed that combine treatments were capable to alter natural microflora positively within chicken cecum contents. Differences were observed in bacterial abundance at both phylum and genus level but did not show significant alteration in alpha diversity due to this treatment. PRACTICAL APPLICATION: The results of this study provide critical information for understanding the potential of synbiotic as an alternative in sustainable poultry farming. The outcomes of this study will lead future direction of using combination of probiotic-derived metabolites and BPE in poultry farming.

Effects of fermented feed on growth performance, immune organ indices, serum biochemical parameters, cecal odorous compound production, and the microbiota community in broilers.

The aim of this study was to explore the effects of dietary fermented feed addition on growth performance, immune organ indices, serum biochemical parameters, cecal odorous compound production, and the bacterial community in broilers. A total of 480 broiler chicks (1-day-old) were randomly assigned to 6 groups, including a basal diet (control group), a basal diet supplemented with 10, 15, 20, and 25% dried fermented feed, and 10% wet fermented feed. Each group contained 8 replicates of 10 chicks each. The results showed that fermentation increased (P < 0.05) the total acid level and the number of Lactobacillus, Yeast, and Bacillus. The 15% dried fermented feed group had an increased (P < 0.05) body weight (BW) than the control, while the 25% dried fermented feed group had the lowest (P < 0.05) BW on 42 d. Compared to the control group, the feed intake (FI) was increased (P < 0.05) in the 10, 15% dried and 10% wet fermented feed groups from 22 to 42 d and from 1 to 42 d. No significant difference (P > 0.05) was observed in feed conversion ratio (FCR) among all groups. Supplementation with fermented feed increased (P < 0.05) the bursa of Fabricius index but not (P > 0.05) the thymus and spleen indices. Compared with the control, the broilers fed fermented feed had increased (P < 0.05) serum total protein, albumin, globulin, IgA, IgG, IgM, lysozyme, complement 3, and complement 4 levels. The cecal concentrations of acetic acid, propionic acid, butyric acid, and lactic acid were increased and the pH values were decreased in the fermented feed groups (P < 0.05). Among the groups, the 15% dried fermented feed group showed the lowest concentrations of skatole and indole in the cecum (P < 0.05). The composition of the cecal microbiota was characterized, in which an increased abundance of Ruminococcaceae, Lactobacillaceae, and unclassified Clostridiales and a decreased abundance of Rikenellaceae, Lachnospiraceae, and Bacteroidaceae were found in the fermented feed groups. Taken together, dietary fermented feed supplementation can improve growth performance, immune organ development, and capacity and decrease cecal odorous compound production, which may be related to the regulation of microbial composition.

Changed cecal microbiota involved in growth depression of broiler chickens induced by immune stress.

A previous study identified genes and metabolites associated with amino acid metabolism, glycerophospholipid metabolism, and inflammatory response in the liver of broilers with immune stress. The present research was designed to investigate the effect of immune stress on the cecal microbiome in broilers. In addition, the correlation between altered microbiota and liver gene expression, the correlation between altered microbiota and serum metabolites were compared using the Spearman correlation coefficients. Eighty broiler chicks were randomly assigned to 2 groups with 4 replicate pens per group and 10 birds per pen. The model broilers were intraperitoneally injected of 250 µg/kg LPS at 12, 14, 33, and 35 d of age to induce immunological stress. Cecal contents were taken after the experiment and kept at -80°C for 16S rDNA gene sequencing. Then the Pearson's correlation between gut microbiome and liver transcriptome, between gut microbiome and serum metabolites were calculated using R software. The results showed that immune stress significantly changed microbiota composition at different taxonomic levels. KEGG pathways analysis suggested that these gut microbiota were mainly involved in biosynthesis of ansamycins, glycan degradation, D-glutamine and D-glutamate metabolism, valine, leucine, and isoleucine biosynthesis and biosynthesis of vancomycin group antibiotics. Moreover, immune stress increased the activities of metabolism of cofactors and vitamins, as well as decreased the ability of energy metabolism and digestive system. Pearson's correlation analysis identified several bacteria were positively correlated with the gene expression while a few of bacteria were negatively correlated with the gene expression. The results identified potential microbiota involvement in growth depression mediated by immune stress and provided strategies such as supplement of probiotic for alleviating immune stress in broiler chickens.

Red osier dogwood extract vs. trimethoprim-sulfadiazine (Part 2). Pharmacodynamic effects on ileal and cecal microbiota of broiler chickens challenged orally with Salmonella Enteritidis.

With the subsisting restrictions on the use of antibiotics in poultry production, the use of plant extracts has shown some promising antimicrobial capacity similar to antibiotics; however, such capacity is largely dependent on their total polyphenol concentration and profile. Given the emerging antimicrobial potential of red osier dogwood (ROD) extract, the study aimed to investigate the pharmacodynamic effect of ROD extract on the ileal and cecal microbiota of broiler chickens challenged orally with Salmonella Enteritidis (SE). A 21 d 4 × 2 factorial experiment was conducted based on 2 main factors, including diets and SE challenge. A total of 384 one-day-old mixed-sex Cobb-500 broiler chicks were randomly allotted to 4 dietary treatments; Negative control (NC), NC + 0.075 mg trimethoprim-sulfadiazine (TMP/SDZ)/kg of diet, and NC containing either 0.3 or 0.5% ROD extract. On d 1, half of the birds were orally challenged with 0.5 mL of phosphate-buffered saline (Noninfected group) and the remaining half with 0.5 mL of 3.1 × 105 CFU/mL SE (Infected group). Dietary treatments were randomly assigned to 8 replicate cages at 6 birds/cage. On d 21, 10 birds/treatment were euthanized and eviscerated to collect ileal and cecal digesta for gut microbiota analysis. The ileal and cecal microbiota was dominated by phyla Firmicutes, Proteobacteria, and Actinobacteriota. The SE infection decreased (P < 0.05) the relative abundance of Proteobacteria and Actinobacteriota in the ileum and ceca, respectively, however, it increased (P < 0.05) Proteobacteria in the ceca. Both 0.3 and 0.5% ROD extracts (P < 0.05) depressed the relative abundance of Actinobacteriota in the ileum but marginally improved (P < 0.05) it in the ceca compared to the TMP/SDZ treatment. Dietary TMP/SDZ increased (P < 0.05) genus Bifidobacterium at the ileal and cecal segments compared to other treatments. Dietary 0.3 and 0.5% marginally improved (P < 0.05) Bifidobacterium in the ceca and depressed (P < 0.05) Weissella and was comparably similar to TMP/SDZ in the ileum. Regardless of the dietary treatments and SE infection, alpha diversity differed (P < 0.05) between ileal and cecal microbiota. Beta diversity was distinct (P < 0.05) in both ileal and cecal digesta along the SE infection model. Conclusively, both ROD extract levels yielded a pharmacodynamic effect similar to antibiotics on ileal and cecal microbiota.

Protective effects of Fagopyrum dibotrys on oxidized oil-induced oxidative stress, intestinal barrier impairment, and altered cecal microbiota in broiler chickens.

The objective of this study was to evaluate protective effects of Fagopyrum dibotrys on antioxidant ability, intestinal barrier functions, and cecal microbiota in broiler chickens fed oxidized soybean oil. A total of 640 male Tiejiaoma broilers were randomly assigned to 8 treatments with 8 cages (10 birds per cage), as follows: birds fed basal diets containing fresh soybean oil and 0, 0.5, 1, or 2% F. dibotrys (FSCON, FSFAL, FSFAM, and FSFAH, respectively), and birds fed basal diets containing oxidized oil and 0, 0.5, 1, or 2% F. dibotrys (OSCON, OSFAL, OSFAM, and OSFAH). Oxidized oil significantly decreased transcription of Nrf2 and its downstream genes, including CAT and SOD1 in the jejunal mucosa, increased jejunal mucosa IL-6 mRNA expression, and decreased jejunal mucosa IL-22 mRNA expression and downregulated Claudin-1 and ZO-1; however, all these effects were reversed by F. dibotrys. Either 1 or 2% F. dibotrys alleviated the decreased liver SOD induced by oxidized oil on d 42. The decreased SOD and GPX, and increased MDA induced by oxidized oil were reversed by adding 1 or 2% F. dibotrys in jejunal mucosa. In addition, based on 16S rDNA, 2% F. dibotrys promoted the Firmicutes phylum and Candidatus_Arthromitus genera, but suppressed the Proteobacteria phylum and Streptococcus, Enterococcus, and Escherichia genera. In summary, oxidative stress induced by oxidized oil was ameliorated by F. dibotrys upregulating transcription of Nrf2 and its downstream genes to restore redox balance, reinforcing the intestinal barrier via higher expression of Claudin-1/ZO-1, ameliorating the inflammatory response by regulating expression of IL-6 and IL-22, and facilitating growth of Candidatus_arthromitus in the cecum. Therefore, F. dibotrys has potential as a feed additive for poultry by ameliorating oxidative stress caused by oxidized oil, enhancing barrier function, and improving gut microbiome composition.

Effects of supplementing organic- and inorganic-based selenium with vitamin E on intestinal histomorphology, caecal bacterial proliferation, and short-chain fatty acid profile in layer hens.

The effects of supplementing different dietary selenium (Se) sources on intestinal histomorphology, caecal bacterial proliferation, and caecum short-chain fatty acid in layer chickens were studied. A total of 120 of 54-week-old Lohman Brown Classic laying hens were subjected to four dietary treatments: control group with no Se supplementation (T1), 0.3 mg/kg of sodium selenite (T2), 0.3 mg/kg of selenium yeast (T3), and 0.3 mg/kg of bacterial Se (Stenotrophomonas maltophilia, ADS18) (T4). All treatments were also supplemented with 250 mg/kg of vitamin E. Results showed significantly (p < 0.05) higher villus height in different small intestine parts in hens fed with diets containing organic Se sources (T3 and T4), as compared to inorganic sources (T2) and control (T1). A greater crypt depth was observed for the T1 group, as compared to T3 and T4 groups. The total bacterial populations of Bifidobacteria spp. and Lactobacilli spp. were significantly increased (p < 0.05), and tEscherichia coli population was significantly decreased (p < 0.05) in T3 and T4 groups. No effect on the total caecal short-chain fatty acid (SCFAs) content was observed. However, there was a significant increase (21.5%) of the butyric acid content in T4 group. In conclusion, organic Se supplementation, particularly bacterial organic Se, enhances intestinal histomorphology, increases the beneficial caecal bacterial proliferation, and increases butyric acid content.

Effects of citrus pulp on the composition and diversity of broiler cecal microbes.

Diet may affect gut microbial composition and diversity. There were 3 dietary groups: 0% citrus pulp diet (C), 1.5% citrus pulp diet (I), and 2.5% citrus pulp diet (II). A total of 180 healthy AA broilers (21-day old) were divided into 3 groups (C, I, and II), each group was set up with 6 replicates, and each replicate including 10 broilers (half male and female). At 42 d, the cecal contents of 18 broiler chickens were collected after slaughter. The cecal contents were analyzed using 16S rRNA sequencing technology. Compared with group C, the abundance of Firmicutes in groups I and II decreased, while the relative abundances of Bacteroidetes, Verrucomicrobia, Lactobacillus, and Faecalibacterium increased. LEfSe analysis showed that Actinobacteria, Coriobacteriia, Coriobacteriales, and Ruminococcaceae_bacterium_Marseille_P2935 in group I were significantly higher than those in group C. Bacteria, Coriobacteriales, Coriobacteriia, Coriobacteriaceae, Slackia, Bacteroides_sp_Marseille_P3132, and Lactobacillus_pontis in group II were significantly higher than those in group C. The Staphylococcaceae, Bacteroides_sp_Marseille_P3132, Macroccus, Lactobacillus_pontis, and Streptococcus_equinus in group II were significantly higher than those in group I. Functional predictions indicated that the cecal microbiota of broilers fed the 2.5% citrus pulp diet was more tend to utilize carbohydrates through glycolytic/gluconeogenesis metabolism. Adding citrus pulp to the diet affects the microbial composition and has important implications for studying gut health and improving economic benefits.

Transcriptome and metabolome analyses reveal the regulatory effects of compound probiotics on cecal metabolism in heat-stressed broilers.

The effect of compound probiotics on the caecum of broilers under heat stress was assessed in this study. A total of 400 twenty-eight-day-old AA male broilers were randomly divided into 4 treatment groups, where each group had 5 replicates of 20 broilers. The 4 treatment groups were a heat stress control group (broilers receiving a normal diet) and groups HP I, HP II, and HP Ⅲ, consisting of broilers receiving 1, 5, and 10 g of compound probiotics added to each kilogram of feed, respectively. Compound probiotics (L. casei, L. acidophilus, and B. lactis at a ratio of 1:1:2) were used to formulate a compound probiotic powder, with 1 × 1010 CFU/g of effective viable bacteria. Heat stress treatment was performed at 32 ± 1°C from 9:00 to 17:00 every day from 28 d to 42 d. In d 28 to 42, compared with the HC group, the ADG of broilers in the HP II and III groups was significantly increased (P < 0.05); the ADFI difference between groups was not significant (P > 0.05); the FCR of HP II and III broilers was significantly decreased (P < 0.05); and the FCR of the HP I group increased, but the difference was not significant (P > 0.05). Transcriptome results demonstrate that 665 differential genes were screened (DEGs; upregulated: 366, downregulated: 299). The DEGs were enriched in the B cell receptor signaling pathway, the intestinal immune network for IgA synthesis, the Fc epsilon RI signaling pathway, and other signaling pathways, according to KEGG enrichment analysis. Metabolome analysis identified 92 differential metabolites (DAMs; upregulated: 48, downregulated: 44). KEGG enrichment analysis indicated significant enrichment of Pantothenate and CoA biosynthesis and beta-Alanine metabolism. The combined transcriptome and metabolome analysis revealed that the DAMs and DEGs were mostly involved in beta-alanine metabolism, arginine biosynthesis, amino sugar and nucleotide sugar, and alanine, aspartate, and glutamate metabolism. The results of this study suggest that the addition of compound probiotics has a positive effect on intestinal metabolites, improving the growth performance and contributing to the overall health of broilers under heat stress.

Enterococcus faecium supplementation prevents enteritis caused by Escherichia coli in goats.

The probiotic Enterococcus faecium is a gut microbe with immunomodulatory effects, which has been widely used to prevent diarrhoea in pigs and birds. Escherichia coli is a common pathogen that causes inflammatory bowel disease in animals. The aim of this study was to investigate the protective effects of E. faecium on enteritis in goats. Forty goats were randomly divided into 4 treatment groups: control, E. faecium, E. coli, and E. faecium + E. coli. The changes of physiological indicators and diarrhoea scoring were evaluated on days -4, -2, 0, 2, 4, 6, and 8. The pathological examination, inflammatory cytokines mRNA expression and bacterial counts in jejunum and caecum were detected on day 4 and 8. The results showed that body temperature, respiratory rate, heart rate and leukocyte counts all increased from the 2nd to the 6th day after feeding with E. coli, and the diarrhoea score was significantly increased. However, E. faecium-pretreated goats had lower body temperatures and fewer leukocytes than E. coli-treated goats on day 2, as well as decreased diarrhoea scores. E. coli treatment caused histopathological damage and morphological changes in the jejunum and caecum, while pretreatment with E. faecium significantly alleviated these injuries. E. faecium pretreatment can reduce the load of E. coli and increase the prevalence of Lactobacillus, thereby balancing the microbiota in the intestine. Furthermore, E. coli-infected goats pretreated with E. faecium showed obvious inhibition of Toll-like receptor 4, interleukin (IL)-1ß, IL-6, IL-8 and tumour necrosis factor-α mRNA expression in the jejunum and caecum compared to that in the E. coli treatment group. In conclusion, the addition of E. faecium to goat feed is beneficial for improving clinical symptoms, maintaining intestinal mucosa integrity, balancing the microbiota and decreasing inflammatory responses in E. coli-induced intestinal injury.

Dietary benzoic acid and supplemental enzymes alter fiber-fermenting taxa and metabolites in the cecum of weaned pigs.

Inclusion of enzymes and organic acids in pig diets is an important strategy supporting decreased antibiotic usage in pork production. However, limited knowledge exists about how these additives impact intestinal microbes and their metabolites. To examine the effects of benzoic acid and enzymes on gut microbiota and metabolome, 160 pigs were assigned to one of four diets 7 days after weaning: a control diet or the addition of 0.5% benzoic acid, 0.045% dietary enzymes (phytase, ß-glucanase, xylanase, and α-amylase), or both and fed ad libitum for 21 to 22 d. Individual growth performance and group diarrhea incidence data were collected throughout the experimental period. A decrease of 20% in pen-level diarrhea incidence from days 8 to 14 in pigs-fed both benzoic acid and enzymes compared to the control diet (P = 0.047). Cecal digesta samples were collected at the end of the experimental period from 40 piglets (n = 10 per group) and evaluated for differences using 16S rRNA sequencing and two-dimensional gas chromatography and time-of-flight mass spectrometry (GCxGC-TOFMS). Analysis of cecal microbiota diversity revealed that benzoic acid altered microbiota composition (Unweighted Unifrac, P = 0.047, r2 = 0.07) and decreased α-diversity (Shannon, P = 0.041; Faith's Phylogenetic Diversity, P = 0.041). Dietary enzymes increased fiber-fermenting bacterial taxa such as Prevotellaceae. Two-step feature selection identified 17 cecal metabolites that differed among diets, including increased microbial cross-feeding product 1,2-propanediol in pigs-fed benzoic acid-containing diets. In conclusion, dietary benzoic acid and enzymes affected the gut microbiota and metabolome of weaned pigs and may support the health and resolution of postweaning diarrhea.

Feeding weaned pigs diets containing benzoic acid or supplemental enzymes for 21 d after weaning changed the gut microbiota and metabolome. Benzoic acid increased feed intake, weight gain, and the presence of 1,2-propanediol in cecal digesta, which is an important microbial cross-feeding product. Dietary enzymes altered microbiota composition, increasing the presence of fiber-fermenting microbes including Prevotellaceae. Pigs fed a combination of both benzoic acid and enzymes showed improved resolution of postweaning diarrhea. These differences demonstrate the role of these feed additives in the establishment of gut microbes and metabolic pathways for the degradation of complex dietary components in the weaned pig. This study provides new information about alterations in microbial function and community composition using microbiota sequencing and metabolomic analysis.

Effect of Probiotic E. coli Nissle 1917 Supplementation on the Growth Performance, Immune Responses, Intestinal Morphology, and Gut Microbes of Campylobacter jejuni Infected Chickens.

Campylobacter jejuni is the most common cause of bacterial foodborne gastroenteritis and holds significant public health importance. The continuing increase of antibiotic-resistant Campylobacter necessitates the development of antibiotic-alternative approaches to control infections in poultry and in humans. Here, we assessed the ability of E. coli Nissle 1917 (EcN; free and chitosan-alginate microencapsulated) to reduce C. jejuni colonization in chickens and measured the effect of EcN on the immune responses, intestinal morphology, and gut microbes of chickens. Our results showed that the supplementation of 3-week-old chickens daily with free EcN in drinking water resulted in a 2.0 log reduction of C. jejuni colonization in the cecum, whereas supplementing EcN orally three times a week, either free or microencapsulated, resulted in 2.0 and 2.5 log reductions of C. jejuni colonization, respectively. Gavaged free and microencapsulated EcN did not have an impact on the evenness or the richness of the cecal microbiota, but it did increase the villous height (VH), crypt depth (CD), and VH:CD ratio in the jejunum and ileum of chickens. Further, the supplementation of EcN (all types) increased C. jejuni-specific and total IgA and IgY antibodies in chicken's serum. Microencapsulated EcN induced the expression of several cytokines and chemokines (1.6 to 4.3-fold), which activate the Th1, Th2, and Th17 pathways. Overall, microencapsulated EcN displayed promising effects as a potential nonantibiotic strategy to control C. jejuni colonization in chickens. Future studies on testing microencapsulated EcN in the feed and water of chickens raised on built-up floor litter would facilitate the development of EcN for industrial applications to control Campylobacter infections in poultry.

Identification of Nordic Berries with Beneficial Effects on Cognitive Outcomes and Gut Microbiota in High-Fat-Fed Middle-Aged C57BL/6J Mice.

High-fat diets are associated with neuronal and memory dysfunction. Berries may be useful in improving age-related memory deficits in humans, as well as in mice receiving high-fat diets. Emerging research has also demonstrated that brain health and cognitive function may be related to the dynamic changes in the gut microbiota. In this study, the impact of Nordic berries on the brain and the gut microbiota was investigated in middle-aged C57BL/6J mice. The mice were fed high-fat diets (60%E fat) supplemented with freeze-dried powder (6% dwb) of bilberry, lingonberry, cloudberry, blueberry, blackcurrant, and sea buckthorn for 4 months. The results suggest that supplementation with bilberry, blackcurrant, blueberry, lingonberry, and (to some extent) cloudberry has beneficial effects on spatial cognition, as seen by the enhanced performance following the T-maze alternation test, as well as a greater proportion of DCX-expressing cells with prolongation in hippocampus. Furthermore, the proportion of the mucosa-associated symbiotic bacteria Akkermansia muciniphila increased by 4-14 times in the cecal microbiota of mice fed diets supplemented with lingonberry, bilberry, sea buckthorn, and blueberry. These findings demonstrate the potential of Nordic berries to preserve memory and cognitive function, and to induce alterations of the gut microbiota composition.

Bacillus licheniformis-fermented products and enramycin differentially modulate microbiota and antibiotic resistome in the cecal digesta of broilers.

Since antibiotic resistance is a global health issues, the use of antibiotics in animal feed for growth promotion has been restricted in many countries. Bacillus licheniformis probiotic is a potential alternative to antibiotics for increasing poultry performance. Through metagenomic sequencing, this study investigated the effects of B. licheniformis-fermented products (BLFPs) and enramycin on the microbial community composition and antibiotic resistance gene (ARG) distribution in the cecal digesta of broilers at the age of 35 d. In total, 144 one-day-old male broiler chicks (Ross 308) were randomly assigned to 4 dietary treatments as follows: basal diet (control [C] group), basal diet plus 10 mg/kg enramycin (E group), basal diet plus 1 g/kg BLFPs (L group), and basal diet plus 3 g/kg BLFPs (H group), with 6 replicate cages per treatment group and 6 birds per cage. The results indicated that the cecal alpha diversity (richness and evenness) of bacterial species was higher in the H group than in the C group. Principal coordinate analysis of microbiota and the ARG composition indicated clear differences among the cecal samples of the groups. In the cecal digesta, the abundance of active bacteria associated with probiotic properties, such as Lactobacillus crispatus and Akkermansia muciniphila, was higher in the H group than in the other groups. Enramycin treatment promoted the expression of peptide (bcrA), glycopeptide (vanRI), and lincosamide (lsaE) resistance genes but inhibited the expression of aminocoumarin (parY) and pleuromutilin (TaeA) resistance genes. BLFP (1 and 3 g/kg) treatment suppressed the expression of aminoglycoside (ANT(6)-Ib), streptogramin (vatB), and peptide (ugd) resistance genes but enhanced the expression of macrolide (efrA) and aminocoumarin (novA) resistance genes. The abundance of peptide resistance genes in Bacteroides spp. was lower in the H group than in the C group. The abundance of lincosamide resistance genes in Lactobacillus spp. was higher in the E group than in the other groups. These results demonstrated that differential changes in the structure of 3 g/kg BLFPs and enramycin-induced cecal microbial communities accompany changes in the abundance of bacterial hosts carrying specific ARGs in the cecal microbiota of broilers.

Effects of therapeutic levels of dietary antibiotics on the cecal microbiome composition of broiler chickens.

Dietary antibiotics, including antibiotic growth promoters (AGPs), have been commonly used to improve health and growth of poultry. The present study investigated the effects of therapeutic doses of dietary antibiotics, including bacitracin methylene disalicylate (BMD), penicillin G potassium (PP) and an ionophore (salinomycin, SA), on the cecal microbiome of chickens. BMD and SA treatments were given as dietary supplements from d 1 to 35 of age. The SAPP (salinomycin+ penicillin G potassium) group was given SA as a dietary supplement from d 1 to 35 of age and PP was added to drinking water from d 19 to 24 of age to simulate common practices for control of necrotic enteritis in broilers. The cecal contents were collected from all treatment groups on d 10, 24, and 35 of age and DNA was extracted for metagenomic analysis of the cecal microbiome. The results revealed that dietary or water supplementation of therapeutic levels of antibiotics and ionophores to chickens significantly altered the cecal microbial homeostasis during different stages of the chicken life. The alpha diversity analysis showed that BMD, SA, and SAPP treatments decreased diversity and evenness of the cecal microbiome of treated chickens on d 10 of age. Species richness was also reduced on d 35 following treatment with BMD. Beta diversity analyses revealed that SAPP and BMD induced significant changes in the relative abundance of Gram-positive and -negative bacteria on d 10, while no significant differences were observed on d 24. On d 35, the non-treated control group had higher relative abundance of unclassified Gram-positive and -negative bacteria compared to SA, SAPP, and BMD treatment groups. Overall, despite their beneficial role in controlling necrotic enteritis outbreaks, the findings of this study highlight the potential negative effects of dietary supplementation of therapeutic levels of antibiotics on the gut microbiome and suggest that adjusting gut bacteria may be required to restore microbial richness and diversity of the gut microbiome following treatment with these antibiotics.