Effect of in feed administration of different butyrate formulations on Salmonella Enteritidis colonization and cecal microbiota in broilers

In silico and PCR Screening for a Live Attenuated Salmonella Typhimurium Vaccine Strain

The application of live attenuated Salmonella Typhimurium vaccines has significantly helped control Salmonella in poultry products. Because the U.S. Department of Agriculture-Food Safety Inspection Service (USDA-FSIS) scores all Salmonella as positive, regardless of serovar, attenuated vaccine strains that are identified at processing contribute negatively toward Salmonella performance standards. This study was designed to determine the incidence of a live attenuated Salmonella serovar Typhimurium vaccine identified in broiler products by FSIS and to develop a PCR assay for screening of isolates. Salmonella Typhimurium short-read sequences from broiler samples uploaded to the National Center for Biotechnology Information (NCBI) Pathogen Detection database by the USDA-FSIS from 2016 to 2022 were downloaded and assembled. These were analyzed using the Basic Local Alignment Search Tool (BLAST) with a sequence unique to field strains, followed by a sequence unique to the vaccine strain. The PCR assays were developed against field and vaccine strains by targeting transposition events in the crp and cya genes and validated by screening Salmonella serovar Typhimurium isolates. Between 2016 and 2022, 1708 Salmonella Typhimurium isolates of chicken origin were found in the NCBI Pathogen Detection database, corresponding to 7.99% of all Salmonella identified. Of these, 104 (5.97%) were identified as the vaccine strain. The PCR assay differentiated field strains from the vaccine strain when applied to isolates and was also able to detect the vaccine strain from DNA isolated from mixed serovar overnight Salmonella enrichment cultures. Live attenuated Salmonella vaccines are a critical preharvest tool for Salmonella control and are widely used in industry. With forthcoming regulations that will likely focus on Salmonella Typhimurium, along with other serovars, there is a need to distinguish between isolates belonging to the vaccine strain and those that are responsible for causing human illness.

Salmonella spp. in poultry production-A review of the role of interventions along the production continuum

Salmonella is a significant pathogen of human and animal health and poultry are one of the most common sources linked with foodborne illness worldwide. Global production of poultry meat and products has increased significantly over the last decade or more as a result of consumer demand and the changing demographics of the world's population, where poultry meat forms a greater part of the diet. In addition, the relatively fast growth rate of birds which is significantly higher than other meat species also plays a role in how poultry production has intensified. In an effort to meet the greater demand for poultry meat and products, modern poultry production and processing practices have changed and practices to target control and reduction of foodborne pathogens such as Salmonella have been implemented. These strategies are implemented along the continuum from parent and grandparent flocks to breeders, the farm and finished broilers to transport and processing and finally from retail to the consumer. This review focuses on common practices, interventions and strategies that have potential impact for the control of Salmonella along the poultry production continuum from farm to plate.

Dietary supplemental coated essential oils and organic acids mixture improves growth performance and gut health along with reduces Salmonella load of broiler chickens infected with Salmonella Enteritidis

BACKGROUND

Reducing Salmonella infection in broiler chickens by using effective and safe alternatives to antibiotics is vital to provide safer poultry meat and minimize the emergence of drug-resistant Salmonella and the spread of salmonellosis to humans. This study was to first evaluate the protective efficacy of feeding coated essential oils and organic acids mixture (EOA) on broiler chickens infected with Salmonella Enteritidis (S. Enteritidis, SE), and then its action mechanism was further explored.

METHODS

A total of 480 1-day-old Arbor Acres male chickens were randomly assigned into five treatments with six replicates, including non-challenged control fed with basal diet (A), SE-challenged control (B), and SE-infected birds fed a basal diet with 300 mg/kg of EOA (BL), 500 mg/kg of EOA (BM) and 800 mg/kg of EOA (BH), respectively. All birds on challenged groups were infected with Salmonella Enteritidis on d 13.  RESULTS: Feeding EOA showed a reversed ability on negative effects caused by SE infection, as evidenced by decreasing the feed conversion rate (FCR) and the ratio of villus height to crypt depth (VH/CD) (P < 0.05), obviously decreasing intestinal and internal organs Salmonella load along with increasing cecal butyric acid-producing bacteria abundance (P < 0.05). Moreover, supplemental different levels of EOA notably up-regulated claudin-1 (CLDN-1), occludin (OCLN), zonula occludens-1 (ZO-1), mucin-2 (MUC-2), fatty acid binding protein-2 (FABP-2), nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), myeloid differential protein-88 (MyD88) and interleukin-6 (IL-6) mRNA levels in the ileum of the infected chickens after challenge, whereas down-regulated toll-like receptor-4 (TLR-4) mRNA levels (P < 0.05). Linear discriminant analysis combined effect size measurements analysis (LEfSe) showed that the relative abundance of g_Butyricicoccus, g_Anaerotruncus and g_unclassified_f_Bacillaceae significantly was enriched in infected birds given EOA. Also, phylogenetic investigation of communities by reconstruction of unobserved states (PICRUSt) analysis showed that alpha-linolenic acid metabolism, fatty acid metabolism and biosynthesis of unsaturated fatty acids were significantly enriched in the EOA group.

CONCLUSION

Our data suggest that the essential oils and organic acids mixture can be used as an effective strategy to ameliorate and alleviate Salmonella Enteritidis infection in broilers.

Uncovering the core principles of the gut-lung axis to enhance innate immunity in the chicken

Research in mammals has evidenced that proper colonization of the gut by a complex commensal microbial community, the gut microbiota (GM), is critical for animal health and wellbeing. It greatly contributes to the control of infectious processes through competition in the microbial environment while supporting proper immune system development and modulating defence mechanisms at distant organ sites such as the lung: a concept named ‘gut-lung axis’. While recent studies point to a role of the GM in boosting immunity and pathogen resilience also in poultry, the mechanisms underlying this role are largely unknown. In spite of this knowledge gap, GM modulation approaches are today considered as one of the most promising strategies to improve animal health and welfare in commercial poultry production, while coping with the societal demand for responsible, sustainable and profitable farming systems. The majority of pathogens causing economically important infectious diseases in poultry are targeting the respiratory and/or gastrointestinal tract. Therefore, a better understanding of the role of the GM in the development and function of the mucosal immune system is crucial for implementing measures to promote animal robustness in commercial poultry production. The importance of early gut colonization in the chicken has been overlooked or neglected in industrial poultry production systems, where chicks are hampered from acquiring a complex GM from the hen. Here we discuss the concept of strengthening mucosal immunity in the chicken through GM modulation approaches favouring immune system development and functioning along the gut-lung axis, which could be put into practice through improved farming systems, early-life GM transfer, feeding strategies and pre-/probiotics. We also provide original data from experiments with germ-free and conventional chickens demonstrating that the gut-lung axis appears to be functional in chickens. These key principles of mucosal immunity are likely to be relevant for a variety of avian diseases and are thus of far-reaching importance for the poultry sector worldwide.

Evaluation of the Potential Protective Effects of Lactobacillus Strains against Helicobacter pylori Infection: A Randomized, Double-Blinded, Placebo-Controlled Trial

BACKGROUND

The beneficial effects of probiotic supplementation standard antibiotic therapies for Helicobacter pylori infection have been verified, but the ability of probiotic monotherapy to eradicate H. pylori remains unclear.

AIM

To evaluate the accuracy and efficacy of specific Lactobacillus strains against H. pylori infection.

METHODS

Seventy-eight patients with H. pylori infection were treated with strain L. crispatus G14-5M (L. crispatus CCFM1118) or L. helveticus M2-09-R02-S146 (L. helveticus CCFM1121) or L. plantarum CCFM8610 at a dose of 2 g twice daily for one month. ¹⁴C-urea breath test, the gastrointestinal symptom rating scale, serum pepsinogen concentrations, and serum cytokine concentrations of patients were measured at baseline and end-of-trial to analyze the effect of the Lactobacillus strains in eradicating H. pylori infection and reducing gastrointestinal discomfort in patients. In addition, the composition and abundance of the intestinal microbiota of patients were also measured at end-of-trial.

RESULTS

The ¹⁴C-urea breath test value of the three Lactobacillus treatment groups had decreased significantly, and the eradication rate of H. pylori had increased by the end of the trial. In particular, the eradication rate in the G14-5M treatment group was significantly higher than the placebo group (70.59% vs. 15.38%, P=0.0039), indicating that one-month administration of the G14-5M regimen was sufficient to eradicate H. pylori infection. The ingestion of Lactobacillus strains also ameliorated the gastrointestinal symptom rating scale scores, and the serum interleukin-8 concentrations of H. pylori-infected patients appeared to modulate the gut microbiota of patients. However, none of the Lactobacillus strains had a significant effect on general blood physiological characteristics, serum tumor necrosis factor α concentrations, or serum pepsinogen concentrations in the patients.

CONCLUSION

Three Lactobacillus strains significantly alleviate the gastrointestinal discomfort and the gastric inflammatory response of H. pylori-infected patients. The activity of probiotics in eradicating H. pyloriinfection may be species/strain specific.

Butyric acid glycerides in the diet of broilers to replace conventional growth promoters: effects on performance, metabolism, and intestinal health

This study aimed to determine whether butyric acid glycerides can replace conventional growth promoters, favour intestinal health, and improve performance. A total of 420 birds were used, divided into four groups with seven repetitions per group (n = 15), as follows: NC, negative control (no promoter); PC, positive control (basal diet + enramycin + salinomycin); MDT-BUT, a diet supplemented with mono-, di-, and triglycerides of butyric acid; TRI-BUT, a diet supplemented with tributyrin of butyric acid glycerides. Productive performance was measured on days 1, 21, 35, and 42. Excreta were collected for counting Escherichia coli and coliforms on days 21 and 42. Blood samples were collected at 42 days of age to analyse oxidant/antioxidant status, and the intestine was removed for intestinal morphometry. From 1 to 42 days, there was greater body weight, weight gain, and feed conversion in the PC, MDT-BUT, and TRI-BUT groups than in the NC group; the production efficiency index was 21.10% higher in all groups than in the NC group (p = 0.001). At 21 days, there were lower E. coli counts of 86.8% in the TRI-BUT and 99.7% in PC groups than in the NC and MDT-BUT groups (p < 0.001), while at 42 days, lower counts were found in the PC, MDT-BUT, and TRI-BUT groups than the NC group (p < 0.001). There were lower total protein and globulin levels in the MDT-BUT and TRI-BUT groups than in the NC group (p = 0.001). Cholesterol levels were lower in the TRI-BUT group, followed by MDT-BUT and PC groups, than in the NC group (p = 0.001), while lower triglyceride levels were found in the TRI-BUT group than in the NC and PC groups (p = 0.001). There were lower levels of lipid peroxidation and reactive oxygen species in the TRI-BUT group, followed by the PC group than the NC group (p < 0.001); on the other hand, there were higher protein thiol levels in the TRI-BUT group than the NC group (p = 0.041). The villus:crypt ratio increase was 79.4% in the TRI-BUT group, followed by the 45.1% PC and 19.8% MDT-BUT groups than the NC (p < 0.001). These findings suggest that adding butyric acid confers antimicrobial and antioxidant activity and improves birds' production efficiency, intestinal health, and metabolism. Butyric acid glycerides are an effective alternative to conventional growth promoters.

The Role of Nutraceuticals and Phytonutrients in Chickens’ Gastrointestinal Diseases

Simple Summary

The use of nutraceuticals and phytonutrients in poultry nutrition has been extensively explored over the past decade. The interest in these substances is linked to the search for natural compounds that can be effectively used to prevent and treat some of the main diseases of the chicken. The serious problem of antibiotic resistance and the consequent legislative constraints on their use required the search for alternatives. The purpose of this review is to describe the current status of the effects of some substances, such as probiotics and prebiotics, organic acids, vitamins and phytogenic feed additives, focusing specifically on studies concerning the prevention and treatment of four main gastrointestinal diseases in chicken: salmonellosis, necrotic enteritis (caused by Clostridium perfringens), campylobacteriosis, and coccidiosis. A brief description of these diseases and the effects of the main bioactive principles of the nutraceutical or phytonutrient groups will be provided. Although there are conflicting results, some works show very promising effects, with a reduction in the bacterial or protozoan load following treatment. Further studies are needed to verify the real effectiveness of these compounds and make them applicable in the field.

Abstract

In poultry, severe gastrointestinal diseases are caused by bacteria and coccidia, with important economic losses in the poultry industry and requirement of treatments which, for years, were based on the use of antibiotics and chemotherapies. Furthermore, Salmonella spp., Clostridium perfringens, and Campylobacter jejuni can cause serious foodborne diseases in people, resulting from consumption of poultry meat, eggs, and derived products. With the spread of antibiotic resistance, which affects both animals and humans, the restriction of antibiotic use in livestock production and the identification of a list of “critically important antimicrobials” became necessary. For this reason, researchers focused on natural compounds and effective alternatives to prevent gastrointestinal disease in poultry. This review summarizes the results of several studies published in the last decade, describing the use of different nutraceutical or phytonutrients in poultry industry. The results of the use of these products are not always encouraging. While some of the alternatives have proven to be very promising, further studies will be needed to verify the efficacy and practical applicability of other compounds.

Effects of Coated Sodium Butyrate and Polysaccharides From Cordyceps cicadae on Intestinal Tissue Morphology and Ileal Microbiome of Squabs

This experiment was conducted to investigate the effects of dietary supplementation with different levels of coated sodium butyrate (CSB) and polysaccharides extracted from Cordyceps cicadae (CCP) on growth performance, intestinal tissue morphology and ileum microbiome in squabs. A total of 420 1-day-old squabs were randomly divided into seven groups with 5 replicates each and 12 squabs per replicate. The squabs were fed basal diet (control group) and basal diet supplemented with different levels of CSB (275, 550, and 1,100 mg/kg, groups CSB-275, CSB-550, CSB-1100) and CCP (27.5, 55, and 110 mg/kg, groups CCP-27.5, CCP-55, and CCP-110), respectively. The experiment was conducted for 28 days. The results revealed that the final BW and average daily gain concentration were higher (P < 0.05) in squabs of CSB-275 and CCP-110 groups than those in the CON group. Comparing with control group, the squabs in the groups CSB-275, CSB-550, and CCP-55 obtained higher villus height/crypt depth (VH/CD) of the duodenum and higher VH of the jejunum (P < 0.05). Operational taxonomic units in the groups CSB-550 and CCP-27.5 were also increased (P < 0.05). Regarding the relative abundance of flora, the Actinobacteria abundance in the groups CSB-550, CSB-1100, and CCP-55 were higher than in control group (P < 0.05), and the Aeriscardovia abundance of CSB-275, CSB-550, CSB-1100, and CCP-110 were elevated (P < 0.05). However, the Enterococcus abundance in CSB-275, CSB-550, CSB-1100, and CCP-27.5 decreased (P < 0.05). In summary, results obtained in the present study indicate that CSB and CCP can improve growth performance, intestinal microbial balance and gut health of squabs.

Impact of Dietary Sodium Butyrate and Salinomycin on Performance and Intestinal Microbiota in a Broiler Gut Leakage Model

Unfavorable alterations of the commensal gut microbiota and dysbacteriosis is a major health problem in the poultry industry. Understanding how dietary intervention alters the microbial ecology of broiler chickens is important for prevention strategies. A trial was conducted with 672 Ross 308 day-old male broilers fed a basic diet (no additives, control) or the basic diet supplemented with 500 mg/kg encapsulated butyrate or 68 mg/kg salinomycin. Enteric challenge was induced by inclusion of 50 g/kg rye in a grower diet and oral gavage of a 10 times overdose of a vaccine against coccidiosis. Compared to control and butyrate-supplemented birds, salinomycin supplementation alleviated growth depression. Compared to butyrate and non-supplemented control, salinomycin increased potentially beneficial Ruminococcaceae and reduced potentially pathogenic Enterobacteriaceae and counts of Lactobacillus salivarius and Clostridium perfringens. Further, salinomycin supplementation was accompanied by a pH decrease and succinic acid increase in ceca, while coated butyrate (0.5 g/kg) showed no or limited effects. Salinomycin alleviated growth depression and maintained intestinal homeostasis in the challenged broilers, while butyrate in the tested concentration showed limited effects. Thus, further investigations are required to identify optimal dietary inclusion rates for butyrate used as alternative to ionophore coccidiostats in broiler production.

Effects of Dietary Tributyrin on Growth Performance, Biochemical Indices, and Intestinal Microbiota of Yellow-Feathered Broilers

This study aimed to evaluate the effects of tributyrin on growth performance, biochemical indices and intestinal microbiota of yellow-feathered broilers. 360 one-day-old chicks were randomly allocated to three treatments with six replicates of 20 chicks each, including a normal control group (NC), an antibiotic group (PC), and a tributyrin (250 mg/kg) group (TB) for 63 days. The results showed that compared with the control, the feed conversion ratio (FCR) in the TB group decreased during the d22 to d42 (p < 0.05) and overall, the final weight and FCR of broilers tended to increase and decrease, respectively. Moreover, the TB group showed the highest creatine concentrations at the entire period (p < 0.05). TB treatment increased the Bacteroidetes relative abundance and decreased Firmicutes. Principal coordinates analysis yielded clear clustering of the three groups. Linear discriminant analysis effect size analysis found seven differentially abundant taxa in the TB group, including several members of Bacteroidedetes. The relative abundance of Eisenbergiella, Phascolarctobacterium, Megasphaera and Intestinimonas increased in tributyrin-treated broilers. Spearman correlation analysis identified a correlation between Eisenbergiella abundance and overall feed efficiency. These results demonstrated that tributyrin could improve the growth performance by modulating blood biochemical indices and the cecal microflora composition of broilers.

The Impact of Tributyrin on Performance and Intestinal Health of Broiler Chickens Post Coccidiosis Vaccination

Coccidiosis is a major intestinal disease affecting broiler chickens. Tributyrin (TB) is a valid alternative to butyrate acid, which was associated with the improvement of performance and attenuation of intestinal inflammation in animal production. However, there are few reports on TB as a prophylactic treatment against coccidiosis in broilers. The aim of the study was to investigate the effects of TB supplementation on performance and intestinal health of broiler chickens post coccidiosis vaccination with a mixed-species Eimeria. In the first experiment, 612 broiler chicks were randomly assigned to two treatments with six replicates. Treatments included no TB supplementation and coccidiosis vaccination (CV1), or TB supplementation (400 mg/kg) and coccidiosis vaccination (TBCV1). On day 5, all broilers received a single vaccine dose. Performance, intestinal histopathology, clinical severity, and fecal oocyst counts were evaluated from day 1 to day 63. TB supplementation resulted in a nonsignificant effect on body weight gain (BWG), feed intake (FI), and mortality-corrected feed conversion ratio (FCR), except in increased FI on days 22-42 (P < 0.05). The TBCV1 group had increased (P < 0.05) villi heights in the duodenum and increased (P < 0.05) villi widths in the ileum on day 63 of age and reduced oocyst shedding on days 19-26 compared to CV1(P < 0.05). The route of administration in the second experiment was different from the first experiment in which the seeder birds (half of birds from each pen) received a tenfold dose on day 5. TB supplementation in broilers resulted in increased (P < 0.05) BWG and reduced (P < 0.05) FCR on days 22-42, and increased (P < 0.05) villi heights in the duodenum and increased (P < 0.05) villi widths in the ileum on day 63 of age, as well as a lower frequency (P < 0.05) of intestinal hemorrhage on days 13-62 and reduced (P < 0.001) oocyst shedding on day 5 post-Eimeria challenge. In conclusion, the study demonstrated that TB can be considered as a feed additive for protecting broilers from coccidiosis on days 22-42.

Dietary Tributyrin Administration Improves Intestinal Morphology and Selected Bacterial and Short-Chain Fatty Acid Profiles in Broilers Under an Isocaloric Feeding Regime

The current study was conducted to investigate the effect of dietary tributyrin (TB) administration on the intestinal and growth performances in Arbor Acres (AA) broilers under an isocaloric feeding regime. A total of 540 day-old healthy AA broilers were randomly assigned to five treatments with 12 replicates (pens) per treatment and nine birds per pen for 42 days. The dietary treatments were basal diet (control) and basal diet with TB at doses of 0.23 g/kg (TB1), 0.46 g/kg (TB2), 0.92 g/kg (TB3), and 1.84 g/kg (TB4). Particularly, to achieve the isocaloric and cost-saving experimental diets, soybean oil was replaced by the TB product (Eucalorie^®) with equivalent metabolic energy contents, and the formulas were rebalanced with zeolite to get the sum of all the feed ingredients to 100%. On days 21 and 42, after weighing, the birds (one bird per replicate) whose body weight was close to the replicate average were euthanized to investigate the effect of dietary TB on intestinal morphology, intestinal bacterial population, and short-chain fatty acid contents. The results revealed that dietary TB administration increased the average daily gain, gain/feed ratio, and European broiler index (P < 0.05) and improved the intestinal morphology (P < 0.05) as indicated by higher villus height and the ratios of villus height/crypt depth in broilers. The incremental levels of TB increased the ileal Lactobacillus content (P = 0.05) and cecal Bacillus content (P = 0.02), respectively. Moreover, dietary TB administration also increased the contents of most of the selected short-chain fatty acids in ileal and cecal digesta (P < 0.05). Collectively, dietary TB administration quadratically improved the growth performance, intestinal morphology, beneficial bacterial population, and short-chain fatty acid levels under the isocaloric feeding regime, indicating better profit return potential in practical poultry operation.

Comparison of Chicken Cecal Microbiota after Metaphylactic Treatment or Following Administration of Feed Additives in a Broiler Farm with Enterococcal Spondylitis History

Minimizing the clinical signs of Enterococcus cecorum infections causing enterococcal spondylitis in broiler herds is successful when initiated as metaphylaxis in the first week of life. Mechanistically, either the Enterococcus species present at that time are reduced by antibiotic treatment or antibiotic treatment might induce changes in intestinal microbiota composition with an indirect and subsequent influence. The aim of the present study was to examine the cecal microbiota of chickens after administering lincospectin or different additives to evaluate whether these additives have lincospectin-like effects on microbiota. Therefore, 157,400 broiler chickens were reared in four chicken houses (~40,000 birds each) on a broiler farm with history of enterococcal spondylitis. Each flock was treated either with lincospectin or water soluble esterified butyrins, Bacillus (B.) licheniformis or palm oil was added via drinking water during the first days of life. Ten birds per house were dissected at days 11, 20 and 33 of life and cecal microbiota were analyzed (16S rRNA gene sequencing). Lincospectin treatment elicited significant changes in the cecal microbiota composition until slaughter age. Among the tested additives, effects of B. licheniformis on cecal microbiota composition were most similar to those seen after the treatment with lincospectin at day 11.

The Effect of α-Monolaurin and Butyrate Supplementation on Broiler Performance and Gut Health in the Absence and Presence of the Antibiotic Growth Promoter Zinc Bacitracin

The use of antibiotic growth promoters (AGP) is common practice to improve broiler production and performance. The use of AGP is under discussion as it can induce bacterial resistance. The purpose of this study was to determine the impact of removing AGP from broiler feed and study the effect of feed additives. For those countries where in-feed AGP are still permitted, the effect of the products in the presence of AGP was evaluated. Half the number of male broilers received a diet free of AGP, whereas the other half received a diet supplemented with zinc bacitracin at 0.5 g/kg. Both diets were either without additional additives or combined with a coated sodium butyrate, α-monolaurin or a combination of these additives. Raised under optimal conditions, the incorporation of AGP had no effect on broiler performance, but negatively affected villi height and villi height to crypt depth (VH:CD) ratio in the duodenum. In the absence of AGP, butyric acid and α-monolaurin had a positive effect on villi height. In the presence of AGP, α-monolaurin resulted in the lowest feed conversion ratio and improved VH:CD ratio in the duodenum, jejunum and ileum. Both feed additives had minimal effect on performance parameters but showed small positive effects on gut health in the absence of AGP and could play a role in the strategy to replace AGP.

Appendectomy and Non-Typhoidal Salmonella Infection: A Population-Based Matched Cohort Study

The potential association between appendectomy and non-typhoidal Salmonella (NTS) infection has not been elucidated. We hypothesized that appendectomy may be associated with gut vulnerability to NTS. The data were retrospectively collected from the Taiwan National Health Insurance Research Database to describe the incidence rates of NTS infection requiring hospital admission among patients with and without an appendectomy. A total of 208,585 individuals aged ≥18 years with an appendectomy were enrolled from January 2000 to December 2012, and compared with a control group of 208,585 individuals who had never received an appendectomy matched by propensity score (1:1) by index year, age, sex, occupation, and comorbidities. An appendectomy was defined by the International Classification of Diseases, Ninth Revision, Clinical Modification Procedure Codes. The main outcome was patients who were hospitalized for NTS. Cox proportional hazards models were applied to estimate the hazard ratios (HRs) and 95% confidence intervals (CIs). Two sensitivity analyses were conducted for cross-validation. Of the 417,170 participants (215,221 (51.6%) male), 208,585 individuals (50.0%) had an appendectomy, and 112 individuals developed NTS infection requiring hospitalization. In the fully adjusted multivariable Cox proportional hazards regression model, the appendectomy group had an increased risk of NTS infection (adjusted HR (aHR), 1.61; 95% CI, 1.20-2.17). Females and individuals aged 18 to 30 years with a history of appendectomy had a statistically higher risk of NTS than the control group (aHR, 1.92; 95% CI, 1.26-2.93 and aHR, 2.67; 95% CI, 1.41-5.07). In this study, appendectomy was positively associated with subsequent hospitalization for NTS. The mechanism behind this association remains uncertain and needs further studies to clarify the interactions between appendectomy and NTS.

Butyrate Improves Skin/Lung Fibrosis and Intestinal Dysbiosis in Bleomycin-Induced Mouse Models

Systemic sclerosis (SSc) is an autoimmune disorder characterized by fibrosis of the skin and internal organs. Despite several studies on SSc treatments, effective treatments for SSc are still lacking. Since evidence suggests an association between intestinal microbiota and SSc, we focused on butyrate, which has beneficial effects in autoimmune diseases as a bacterial metabolite. Here, we investigated the therapeutic potential of sodium butyrate (SB) using a bleomycin-induced fibrosis mouse model of SSc and human dermal fibroblasts (HDFs). SB attenuated bleomycin-induced dermal and lung fibrosis in mice. SB influenced fecal microbiota composition (phyla Actinobacteria and Bacteroidetes, genera Bifidobacterium and Ruminococcus_g2). SB controlled macrophage differentiation in mesenteric lymph nodes, spleen, and bronchoalveolar lavage cells of mice with bleomycin-induced skin fibrosis. Profibrotic and proinflammatory gene expression was suppressed by SB administration in skin. Furthermore, SB inhibited transforming growth factor β1-responsive proinflammatory expression with increased acetylation of histone 3 in HDFs. Subcutaneous SB application had antifibrogenic effects on the skin. Butyrate ameliorated skin and lung fibrosis by improving anti-inflammatory activity in a mouse model of SSc. Butyrate may exhibit indirect and direct anti-fibrogenic action on fibroblasts by regulating macrophage differentiation and inhibition of histone deacetylase 3. These findings suggest butyrate as an SSc treatment.

Effects of monobutyrin supplementation on egg production, biochemical indexes, and gut microbiota of broiler breeders

The objective of the present study was to determine the effect of monobutyrin supplementation on egg production, biochemical indexes, and gut microbiota of broiler breeders at the late stage of production. A total of 180 healthy Qingyuan partridge broilers were randomly assigned to 2 groups: 1) corn-soybean meal-based diet and 2) basal diet supplemented with 250 mg monobutyrin/kg. Each treatment group had 6 replicates/cages with 15 birds within each replicate. The experiment started at week 33 and lasted for 8 wk. Egg production rate, feed conversion rate, shell breaking strength, and shell thickness were not different between control and treatment groups. Supplementation of monobutyrin increased egg weight and tended to decrease egg breaking rate of Qingyuan partridge chickens. Supplementation of monobutyrin did not affect any of the biochemical indexes except total protein concentration. The 4 antioxidant parameters measured were not affected either. Alpha diversity indexes (Shannon, Simpson, Chao1, Ace, and Good's Coverage) and composition of cecal microbiota were not affected by monobutyrin supplementation. Overall, supplementation of monobutyrin at 250 mg/kg level improved egg quality, but its effect on cecal microbiota composition was limited.