Effect of supplementation of yeast with bacteriocin and Lactobacillus culture on growth performance, cecal fermentation, microbiota composition, and blood characteristics in broiler chickens

Ammonia negatively impacted egg production and altered the diversity of microbial communities in cage-reared Muscovy ducks

The aim of this study was to examine the effects of NH3 variations across different positions within a cage-reared duck house on the egg production performance and fecal microbiome in Muscovy ducks. Totals of 3,168 female Muscovy ducks (180 ± 2 d) were randomly assigned to 1,056 cages. From d 293 to 300, the egg production rate and levels of NH3, H2S, CO2, temperature, humidity, light intensity, and dust particles were recorded. Two spatial distribution-based experimental classification methods were applied, one grouping ducks into Front, Middle, and End categories, and the other into First, Second, and Third layers. On d 300, serum and feces samples were collected for further analysis. The result showed that both the egg production rate and serum PROG level in the Front were higher than End (P < 0.05). However, no significant differences were found among the First, Second, and Third groups. Among the environmental factors, ammonia (NH3) is a major harmful gas in cage-reared duck houses, with observed concentrations showing a gradient from lower levels in the Front group to higher levels in the Middle group (P < 0.05), and even higher levels in the End group (P < 0.05). Gene sequencing of the 16S rRNA gene revealed a higher relative abundance of Firmicutes in both the Front and Middle groups compared to the End group (P < 0.05). Specifically, within the Firmicutes phylum, the relative abundance of Lactobacillus and Romboutsia was notably higher in the Front group compared to both the Middle and End groups (P < 0.05). What's more, the abundance of Lactobacillus had a negative correlation with NH3 concentration and positive correlation with egg production rate. In conclusion, NH3 concentrations showed variations across different areas of the cage-reared duck house, with higher levels detected at the rear. The elevated NH3 level was identified as the main factor negatively impacting egg production in Muscovy ducks and contributing to a decline in the abundance of Firmicutes, specifically Lactobacillus.

Combined effect of microbially derived cecal SCFA and host genetics on feed efficiency in broiler chickens

BACKGROUND

Improving feed efficiency is the most important goal for modern animal production. The regulatory mechanisms of controlling feed efficiency traits are extremely complex and include the functions related to host genetics and gut microbiota. Short-chain fatty acids (SCFAs), as significant metabolites of microbiota, could be used to refine the combined effect of host genetics and gut microbiota. However, the association of SCFAs with the gut microbiota and host genetics for regulating feed efficiency is far from understood.

RESULTS

In this study, 464 broilers were housed for RFI measuring and examining the host genome sequence. And 300 broilers were examined for cecal microbial data and SCFA concentration. Genome-wide association studies (GWAS) showed that four out of seven SCFAs had significant associations with genome variants. One locus (chr4: 29414391-29417189), located near or inside the genes MAML3, SETD7, and MGST2, was significantly associated with propionate and had a modest effect on feed efficiency traits and the microbiota. The genetic effect of the top SNP explained 8.43% variance of propionate. Individuals with genotype AA had significantly different propionate concentrations (0.074 vs. 0.131 μg/mg), feed efficiency (FCR: 1.658 vs. 1.685), and relative abundance of 14 taxa compared to those with the GG genotype. Christensenellaceae and Christensenellaceae_R-7_group were associated with feed efficiency, propionate concentration, the top SNP genotypes, and lipid metabolism. Individuals with a higher cecal abundance of these taxa showed better feed efficiency and lower concentrations of caecal SCFAs.

CONCLUSION

Our study provides strong evidence of the pathway that host genome variants affect the cecal SCFA by influencing caecal microbiota and then regulating feed efficiency. The cecal taxa Christensenellaceae and Christensenellaceae_R-7_group were identified as representative taxa contributing to the combined effect of host genetics and SCFAs on chicken feed efficiency. These findings provided strong evidence of the combined effect of host genetics and gut microbial SCFAs in regulating feed efficiency traits. Video Abstract.

Tannic Acid Induces Intestinal Dysfunction and Intestinal Microbial Dysregulation in Brandt's Voles (Lasiopodomys brandtii)

Brandt's vole (Lasiopodomys brandtii) is a small herbivorous mammal that feeds on plants rich in secondary metabolites (PSMs), including tannins. However, plant defense mechanisms against herbivory by Brandt's voles are not clearly established. This study aimed to investigate the effects of dietary tannic acid (TA) on the growth performance, intestinal morphology, digestive enzyme activities, cecal fermentation, intestinal barrier function, and gut microbiota in Brandt's voles. The results showed that TA significantly hindered body weight gain, reduced daily food intake, changed the intestinal morphology, reduced digestive enzyme activity, and increased the serum zonulin levels (p < 0.05). The number of intestinal goblet and mast cells and the levels of serum cytokines and immunoglobulins (IgA, IgG, TNF-α, IL-6, and duodenal SlgA) were all reduced by TA (p < 0.05). Moreover, TA altered β-diversity in the colonic microbial community (p < 0.05). In conclusion, the results indicate that TA could damage the intestinal function of Brandt's voles by altering their intestinal morphology, decreasing digestive ability and intestinal barrier function, and altering microbiota composition. Our study investigated the effects of natural PSMs on the intestinal function of wildlife and improved our general understanding of plant-herbivore interactions and the ecological role of PSMs.

Week-Old Chicks with High Bacteroides Abundance Have Increased Short-Chain Fatty Acids and Reduced Markers of Gut Inflammation

As important commensals in the chicken intestine, Bacteroides are essential complex carbohydrate degraders, and short-chain fatty acid (SCFA) producers that are highly adapted to the distal gut. Previous studies have shown large variation in Bacteroides abundance in young chickens. However, limited information is available regarding how this variation affects the gut microbiome and host immunity. To investigate how elevated or depleted Bacteroides levels affect gut microbial functional capacity and impact host response, we sampled 7-day-old broiler chickens from 14 commercial production flocks. Week-old broiler chickens were screened and birds with low Bacteroides (LB) and high Bacteroides (HB) abundance were identified via 16S rRNA gene amplicon sequencing and quantitative PCR (qPCR) assays. Cecal microbial functionality and SCFA concentration of chickens with distinct cecal Bacteroides abundance were profiled by shotgun metagenomic sequencing and gas chromatography, respectively. The intestinal immune responses of LB and HB chickens were assessed via reverse transcription qPCR. Results showed that the gut microbiota of the LB group had increased abundance of lactic acid bacteria pyruvate fermentation pathway, whereas complex polysaccharide degradation and SCFA production pathways were enriched in the HB group (P < 0.05), which was supported by increased SCFA concentrations in the ceca of HB chickens (P < 0.05). HB chickens also showed decreased expression of interleukin-1β and increased expression of interleukin-10 and tight-junction protein claudin-1 (P < 0.05). Overall, the results indicated that elevated Bacteroides may benefit the 7-day broiler gut and that further work should be done to confirm the causal role of Bacteroides in the observed positive outcomes. IMPORTANCE To date, limited information is available comparing distinct Bacteroides compositions in the chicken gut microbial communities, particularly in the context of microbial functional capacities and host responses. This study showed that possessing a microbiome with elevated Bacteroides in early life may confer beneficial effects to the chicken host, particularly in improving SCFA production and gut health. This study is among the first metagenomic studies focusing on the early life chicken gut microbiota structure, microbial functionality, and host immune responses. We believe that it will offer insights to future studies on broiler gut microbial population and their effects on host health.

Lactobacillus (L. plantarum & L. rhamnosus) and Saccharomyces (S. cerevisiae): effects on performance, biochemical parameters, ammonium ion in manure, and digestibility of broiler chickens

Two strains of Lactobacillus combined with Baker's yeast (Saccharomyces cerevisiae) used as probiotics were evaluated to replace antibiotics in poultry flocks by reducing ammonia emissions in manure of broilers without comprising performance or health. One-day-old Cobb 500 broilers (600) were fed starter, grower, and finisher diets as control (CON); probiotic S. cerevisiae, inclusion rate at 4.26 × 10⁶ CFU/kg of feed (SCY); probiotic L. plantarum and L. rhamnosus, inclusion rate at 4.35 × 10⁸ CFU/kg of feed (LPR) for each; and a combination of Lactobacillus plantarum and L. rhamnosus at 4.35 × 10⁸ CFU/kg of feed for each plus Saccharomyces cerevisiae and 4.26 × 10⁶ CFU/kg of feed (SWL). The 4 treatments had 5 replicates (pens), each with 30 broilers. Performance was measured weekly as feed consumption, weight gain, BW, and feed conversion ratio (FCR) over a 6-wk grow-out period. Accompanying biochemical analyses included lipase activity of the pancreas, liver weight, and uric acid (UA) concentration in liver. Albumin, total protein, UA, ammonia, and blood urea nitrogen (BUN) were measured in serum. Ammonium (NH₄⁺) in manure and apparent ileal digestibility from digesta were also measured. Significance was determined at P ≤ 0.05. Results showed that biochemical analyses had no significant treatment effect; however, there were significant temporal changes in performance measures for individual treatments. Feed consumption increased over time for all treatments (P = 2.00 × 10^-16). CON had lower weight gain in wk 2 (P = 0.013) compared to all treatment and the lowest BW in wk 5 (P = 0.0008) and wk 6 (P = 0.0124) compared to SWL. Specific probiotic strains, with well-defined inclusion rates, and surrounding environmental analyses of present microbes are needed to ascertain effects of probiotics. Other important areas for investigation include 1) confirmation of probiotics present in the digesta/ceca and how they alter the microbiota within the gastrointestinal (GI) tract and 2) the serum heterophil:lymphocyte ratio to further examine potential immune responses to the probiotics.

Properties of binderless bamboo particleboards derived from biologically fermented bamboo green residues

In this study, a new type of binderless particleboard was prepared from bamboo green residues processed by biological fermentation. Bamboo green residues were fermented using lactic acid bacteria microorganisms, and binderless bamboo particleboards were prepared by hot pressing. The effects of the fermentation time on the morphological characteristics and chemical components of the residues were investigated. Further, the vertical density profile, internal bonding, and other physical and mechanical properties of the binderless bamboo particleboard were examined. The results revealed that the slenderness ratio of flakes decreased at first and then increased with an increase in the fermentation time (in days), and the chemical components of the bamboo green residues degraded with time. The features of the fermented flakes affect the performance of the prepared particleboard. The physical and mechanical properties of the binderless bamboo particleboards prepared from fine residues obtained after 7 days of fermentation were better than those prepared using the coarse and mixed groups, and met the requirements of the chinese standard GB/T4897-2015. This novel preparation method of binderless bamboo particleboard is helpful to develop a new eco-friendly building material.

Effects of Yeast Culture Supplementation on Growth Performance, Nutrient Digestibility, Blood Metabolites, and Immune Response in Geese

The present study was conducted to investigate the effects of dietary yeast culture (YC) supplementation on growth performance, nutrient digestibility, blood metabolites, and immune functions in geese. One-day-old Sichuan white geese (n = 300) were randomly divided into five groups containing 0 (control), 0.5%, 1.0%, 2.0%, and 4.0% of YC in the diet for 70 days. In general, the dietary supplementation of YC significantly increased the average daily gain and feed conversion ratio (p < 0.05) in which the 1.0% or 2.0% levels were better and significantly reduced the average daily feed intake at the 2.0% level (p < 0.05). YC supplementation increased digestibility of P (quadratic, p = 0.01) and gross energy (quadratic, p = 0.04) from days 23 to 27 and crude protein from days 23 to 27 and days 64 to 68 (quadratic, p ≤ 0.05), with the 2.0% level being the most effective. Serum metabolites were significantly affected by dietary YC (p < 0.05). Supplemental YC increased IL-2 on day 28 (linear, p = 0.01; quadratic, p = 0.04) and lysozyme on day 70 (quadratic, p = 0.04) and decreased complement C4 on day 70 (linear, p = 0.05). Interferon-γ, interleukin-2, and tumor necrosis factor-α genes were mostly up-regulated after YC supplementation, and interferon-γ and interleukin-2 gene expression levels were significantly increased at the 2.0% level (p < 0.05). Taken together, dietary YC supplementation improved growth performance and affected nutrient digestibility, serum metabolites, and immune function in geese, which was optimized at the 2% YC level in the present study.

Effects of supplementation of probiotics instead of antibiotics to broiler diet on growth performance, nutrient retention, and cecal microbiology

Objectives:

The research was carried out on broilers to determine the efficacy of probiotics (Bacillus subtilis and Saccharomyces boulardii combined) supplementation on growth performances, nutrient retention (metabolizable energy, dry matter, and crude protein), and cecal microbiology (Bifidobacteria spp., Clostridium spp., and coliforms).

Materials and Methods:

A total of 160 broiler chicks (day-old) were selected and differentiated randomly into 4 groups (T₀, T₁, T₂, and T₃) (40 × 4) comprising 40 birds in every single group. The control group (T₀) was fed commercial broiler feed only and the other three groups, referred to as treatment groups (T₁, T₂, and T₃), were treated with 1 gm ciprofloxacin, 1 gm probiotic, and 1 gm probiotic plus 0.5 gm enzyme, respectively, in per liter of fresh dietary water 8 h daily for 7 days in each phase. Experimental trials were divided into 2 phases, the starter phase from day 0 to 21 and the finisher phase from day 22 to 35.

Results:

Bodyweight gain and nutrient retention in experimental broiler birds in treatment groups were significantly (p < 0.05) higher than the control group. Overall body weight gain and nutrient retention of broiler chicks in treatment groups T₂ and T₃ were better than T₁. From day 22 to 35, cecal Clostridium and coliform bacterial load counts were significantly lower p < 0.01, p < 0.05, and p < 0.01, respectively, in T₁, T₂, and T₃ treatments than T₀. Overall, Clostridium and coliform bacterial counts in the birds of treatment group T₂ were significantly lower (p < 0.05) than T₀.

Conclusion:

The probiotics, in addition to enzyme supplementation, had suitable influence effects on growth performance of broilers, birds retention of nutrient, and microfloral count in birds’ cecum.

Positive effects of dietary probiotics on immune response and gut morphometry in broiler chickens

n experiment was performed with a total of 280 one-day old SPF broiler chicks to evaluate the effects of probiotics, alone or in combination, on growth performance, gut morphometry and immune response to fowl cholera vaccination. The birds were randomly divided into seven groups each of 40 chicks and the experiment lasted for 42 days. The probiotic microorganisms that were offered via water included Lactobacillus acidophilus, Bifidobacterium bifidum, Enterococcus faecium, Bacillus subtilis and Saccharomyces cervisiae. Significant increase in the food conversion rate was recorded in group 4 that received probiotic mixture composed of Lactobacillus acidophilus and Bacillus subtilis. Also, significantly high geometric mean titre (GMT) of P. multocida specific-antibodies and lowest morbidity and mortality rates post P. multocida challenge were recorded in this group. The effect of different probiotics on the morphometric changes in the gut tissues was determined, where significant increase in the duodenal and ileum villus height and average crypt depth were recorded in probiotic treated chicks compared to the negative control. The increase in the gut villi height is proved to be associated with increased absorption capability of nutients from the intestine.

Stable Recombinant-Gene Expression from a Ligilactobacillus Live Bacterial Vector via Chromosomal Integration

Disease control in animal production systems requires constant vigilance. Historically, the application of in-feed antibiotics to control bacteria and improve performance has been a much-used approach to maintain animal health and welfare. However, the widespread use of in-feed antibiotics is thought to increase the risk of antibiotic resistance developing. Alternative methods to control disease and maintain productivity need to be developed. Live vaccination is useful in preventing colonization of mucosa-dwelling pathogens by inducing a mucosal immune response. Native poultry isolate Ligilactobacillus agilis La3 (previously Lactobacillus agilis) has been identified as a candidate for use as a live vector to deliver therapeutic proteins such as bacteriocins, phage endolysins, or vaccine antigens to the gastrointestinal tract of chickens. In this study, the complete genome sequence of L. agilis La3 was determined and transcriptome analysis was undertaken to identify highly expressed genes. Predicted promoter regions and ribosomal binding sites from constitutively expressed genes were used to construct recombinant protein expression cassettes. A series of double-crossover shuttle plasmids were constructed to facilitate rapid selectable integration of expression cassettes into the L agilis La3 chromosome via homologous recombination. Inserts showed 100% stable integration over 100 generations without selection. A positive relationship was found between protein expression levels and the predicted strength of the promoters. Using this system, stable chromosomal expression of a Clostridium perfringens antigen, rNetB, was demonstrated without selection. Finally, two recombinant strains, L agilis La3::P _eft -rnetB and L agilis La3::P _cwah -rnetB, were constructed and characterized, and they showed potential for future application as live vaccines in chickens.IMPORTANCE Therapeutic proteins such as antigens can be used to prevent infectious diseases in poultry. However, traditional vaccine delivery by intramuscular or subcutaneous injection generally has not proven effective for mucosa-dwelling microorganisms that live within the gastrointestinal tract. Utilizing live bacteria to deliver vaccine antigens directly to the gut immune system can overcome some of the limitations of conventional vaccination. In this work, Ligilactobacillus agilis La3, an especially effective gut colonizer, has been analyzed and engineered with modular and stable expression systems to produce recombinant proteins. To demonstrate the effectiveness of the system, expression of a vaccine antigen from poultry pathogen Clostridium perfringens was monitored over 100 generations without selection and found to be completely stable. This study demonstrates the development of genetic tools and novel constitutive expression systems and further development of L. agilis La3 as a live delivery vehicle for recombinant proteins.

The role of the vaginal microbiome in distinguishing female chronic pelvic pain caused by endometriosis/adenomyosis

Background

This study aimed to investigate the specific vaginal microbiome in the differential diagnosis of endometriosis/adenomyosis (EM/AM)-associated chronic pelvic pain (CPP) from other types of CPP, and to explore the role of the vaginal microbiome in the mechanism of EM/AM-associated CPP.

Methods

We recruited 37 women with EM/AM-associated CPP, 25 women with chronic pelvic pain syndrome (CPPS) without EM/AM, and 66 women without CPPS into our study. All of the participants were free from human papillomavirus (HPV) infection. Sequencing of barcoded 16S rRNA gene fragments (V4) was used to determine the vaginal microbiome composition on the Illumina HiSeq2500 System. Taxonomic and functional bioinformatics analyses were performed using t-test, linear discriminant analysis effect size (LEfSe), MetaStat, and PICRUSt algorithms.

Results

At the species level, EM/AM-associated CPP was found to be associated with a predominance of Clostridium butyricum, Clostridium disporicum, Alloscardovia omnicolens, and Veillonella montpellierensis, and a concomitant paucity of Lactobacillus jensenii, Lactobacillus reuteri, and Lactobacillus iners. When the relative abundance of Clostridium disporicum was over 0.001105% and that of Lactobacillus reuteri was under 0.1911349%, the differential diagnostic sensitivity and specificity were 81.08% and 52.0%, respectively. When serum CA125 was combined, the sensitivity increased to 89.19%, but the specificity remained at 52.0%. The PICRUSt results identified 7 differentially regulated pathways within the 3 groups that may be of relevance.

Conclusions

Compared to that of CPPS patients without EM/AM and women without CPPS, the vaginal microbiome of patients with EM/AM-associated CPP shows significantly higher alpha (phylogenetic) diversity, as well as higher counts of Clostridium butyricum, Clostridium disporicum, Alloscardovia omnicolens, and Veillonella montpellierensis. These differences in the vaginal microbiome may interfere with local functional pathways, which could provide a direction for innovative metabolite-specific targeted treatment. The combination of vaginal biomarkers and serum CA125 may provide an original method to differentiate EM/AM-associated CPP.

Effect of Lactobacillus Species Probiotics on Growth Performance of Dual-Purpose Chicken

Introduction

In-feed probiotics are becoming attractive alternatives to antibiotics in the poultry industry due to the ever-growing strict prohibitions on antibiotic growth promoters (AGP) in animal production.

Methods

The study was conducted to investigate the effects of Lactobacillus paracaseis sparacasei and Lactobacillus rhamnosus on the growth performance of 120 day-olds randomly selected Sasso dual-purpose chicken. They were divided into four groups with two replicates per group and 15 chicks per replicate. The treatments were T₁ (control), T₂ (supplement diet with 4g probiotic), T₃ (supplement diet with 2g probiotic), T₄ (supplement diet with 1g probiotic). The experimental feeding trials were conducted after two weeks adaptation period.

Results

The present findings revealed that the chickens supplemented with Lactobacillus species probiotics during the first week of age have shown higher body weight than control (p < 0.05). The feed intake of week one of T₂ and T₃ were significantly higher (p< 0.05) than the T₁ (control). However, there was no significant difference (p> 0.05) in feed intake in the 2^nd, 3^rd, 4^th, and 5^{t h} weeks of all treatment groups. The present result showed that there was a significant body weight gain (p< 0.05) in all probiotic fed groups than the control group. The highest body weight gain was observed in chickens found in the T4 treatment group. Whereas the body weight gains significantly higher and improved the feed conversion (p<0.05) in the T₂ and T₄ than the T₁ (control). However, the feed conversion ratio was significantly influenced by probiotic inclusion in T₃ as compared to the control group.

Conclusion

Overall, the results suggest that Lactobacillus paracaseis sparacasei and Lactobacillus rhamnosus have a positive effect on the growth performance of broilers.

Effects of Raw and Fermented Rapeseed Cake on Growth Performance, Methane Production, and Breast Meat Fatty Acid Composition in Broiler Chickens

The study was conducted to evaluate the effects of partial replacement of soybean meal (SBM) by 15% raw or fermented rapeseed cake (RRC or FRC) to broilers' diets on growth performance, nutrient utilization, methane emission, and breast muscle fatty acid (FA) composition. A total of 420 one-day-old female Ros 308 broilers were used in three independent experiments (300 birds in the first experiment and 60 in the second and third experiments). In each trial, three treatments were set up: a control group (without rapeseed), and diets replaced soybean meal with 15% addition of RRC or FRC. Birds fed the FRC diet experienced no effect (p > 0.05) on performance or nutrients utilization. Methane emission and total methanogen population in the ceca was decreased (p < 0.05) with the FRC diet. The concentrations of n-3 and n-6 FAs in the breast tissue of fourteen-day-old birds were not affected (p > 0.05) by FRC. However, the n-6/n-3 ratio in the breast muscle of 28-day-old birds was reduced (p < 0.001). In conclusion, the replacement of SBM by FRC in the broiler diets did not show any unfavorable effects on performance or nutrient utilization. Furthermore, the breast meat FA profile was improved, methanogen counts significantly decreased, and methane emission was limited.

Prospects of yeast based feed additives in poultry nutrition: Potential effects and applications

Yeast and its derivatives are extensively utilized as feed additives in poultry industry owing to their desirable health and growth promoting effects. Exhaustive number of studies had reported positive effects of yeast based additives on growth, meat quality, immunity, antioxidant status, and gastrointestinal functions in poultry birds. Owing to their prebiotic/probiotic properties, they also play significant role in gut development and modulation of gut microbiome by favouring beneficial microbes while reducing colonization of pathogenic microbes by competitive exclusion. They also possess effective potential for binding of dietary toxins in addition to improving digestion and utilization of nutrients. Moreover, yeast based additives have exhibited desirable effects on humoral immunity by increasing serum immunoglobulin (Ig) A levels. These additives have been also used as immune adjuvants to boost innate immune response under any pathogenic challenges in birds. Due to their diverse biological activities, yeast products are potentially capable for immune hemostasis by mediating balance between pro- and anti-inflammatory activities. These unique properties of yeast based products make them promising feed additive to promote health and productivity leading to efficient poultry production. Yeast can be supplemented in poultry diets @ 5.0–10.0 g/kg of feed. Numerous studies had reported significant improvement in body weight gain (3 to 8%) and FCR (1.6 to 12%) in broilers in response to supplementation of yeast based additives. Moreover, yeast supplementation also improved hemoglobin (Hb g/dl) levels up to 2.59 to 6.62%, total protein (>0.69%) while reducing serum cholesterol (mg/dl) up to 3.68 to 13.38%. Despite the potential properties and beneficial effects, use of yeast and its derivatives as feed additives in poultry industry is not matching its inherent potential due to many reasons. This review aims to highlight the importance and potential role of yeast and its products as natural growth promoter to replace in feed antibiotics to address the issues of antibiotic residues and microbial resistance. This article provides insights on functional role of yeast based additives in poultry diets and their importance as commercially viable alternatives of antibiotic growth promoters in poultry feed industry.

Features and applications of Ent35-MccV hybrid bacteriocin: current state and perspectives

Bacteriocins are peptides of ribosomal synthesis that are active against bacteria related to the producing strain. They have been widely used in the food industry as biopreservatives. The generation of hybrid peptides by combining the genes that encode two different bacteriocins has made it possible to study the mechanisms of action of the bacteriocins that compose them and also develop new peptides with improved biotechnological applications. Hybrid bacteriocins may be obtained in several ways. In our laboratory, by combining enterocin CRL35 and microcin V (Ent35-MccV), we obtained a broad-spectrum peptide that is active against both Gram-positive and Gram-negative bacteria. Ent35-MccV is sensitive to the action of intestinal proteases and is heat resistant, which makes it a good candidate for use as a biopreservative. For this reason, the peptide was tested in skim milk and beef burgers as food models. We also obtained more potent variants of the hybrid by modifying the central amino acid of the hinge region that connects the two bacteriocins. This review also discusses future applications and perspectives regarding the Ent35-MccV and other hybrid peptides.Key Points• Ent35-MccV is a new broad-spectrum bacteriocin.• The mechanism of action of bacteriocins can be studied using hybrid peptides.• Genetic engineering allows obtaining improved bacteriocin derivatives.• Hybrid peptides can be used in the food, pharmaceutical, and veterinary applications.

Effect of Yeast Culture (Saccharomyces cerevisiae) on Broilers: A Preliminary Study on the Effective Components of Yeast Culture

Simple Summary

The value of yeast culture (YC) as alternative feed additives in poultry farming has been proven. YC is a nutrient-rich and complex micro-ecological fermentation product containing various metabolites. However, the major or specific effective components of YC and their importance in poultry farming are unknown. Herein, we screened the “effective ingredients” of YCs obtained from different fermentation times based on metabolomics and animal feeding experiments. Glycine, fructose, inositol, galactose, and sucrose were identified as potential effective metabolites in YCs. These findings provide an important basis for objective, accurate, and quick evaluation of the quality of YC products, as well as a scientific understanding of their functions.

Abstract

This study was aimed at determining the effective ingredients of yeast culture (YC) for animal breeding. First, the contents of YCs obtained from various fermentation times were detected using gas-chromatography. A total of 85 compounds were identified. Next, 336 Arbor Acres (AA) broilers were randomly divided into seven experimental groups and fed a basal diet, diets supplemented with YCs obtained at various fermentation times, or SZ1 (a commercial YC product). A significant increase in body weight gain (BWG) and a significant decrease in feed conversion ratio (FCR) of AA broiler chicks were observed with YC supplementation. Additionally, most of blood and immunological indices were improved with YC supplementation. According to the production performance and the results of multivariate analysis, glycine, fructose, inositol, galactose, and sucrose were found as the potential effective compounds of YC and were involved in metabolic pathways including glycine, serine, and threonine metabolism. Supplementation with diets based on combinations of effective compounds improved weight gain, feed efficiency, serum immunoglobulin A, and immunoglobulin G, but decreased blood urea concentration. These findings suggest YCs as effective and harmless feed additives with improved nutritional properties for broiler chicks.

Effects of yeast cultures with different fermentation times on the growth performance, caecal microbial community and metabolite profile of broilers

The objective of this study was to investigate the effects of yeast culture (YC) on the growth performance, caecal microbial community and metabolic profile of broilers. A total of 350 1-day-old healthy Arbor Acres broilers were randomly assigned to seven treatment groups. The first group received a basal diet without YC supplementation, whereas the remaining groups received a basal diet supplemented with either YC fermented for 12, 24, 36, 48 or 60 hr, or a commercial YC product (SZ2). MiSeq 16S rRNA high-throughput sequencing was used to investigate the bacterial community structure, and gas chromatography-mass spectrometry was used to identify the metabolites in the caeca of broilers. The broilers that received a diet supplemented with YC had a higher average daily gain and average daily feed intake than those received YC-free or SZ2-enriched diets. The feed conversion ratio (FCR) of YCs fermented for 24 hr resulted in the best feed efficiency, whereas the FCR of YC fermented for 60 hr resulted in poor feed efficiency (p < .05). In the caeca of broilers, the bacterial communities were well separated, as determined by principal component analysis, and the proportions of the eight genera were significantly different among the seven groups (p < .05). The genus Akkermansia was the most abundant when the diet supplemented with YC fermented for 24 hr (p < .05). Furthermore, the Firmicutes/Bacteroidetes ratio was positively correlated with the FCR in the caecum (r = .47, p < .005). Five differentially expressed metabolites (i.e., L-alanine, benzeneacetic acid, D-mannose, D-arabitol and cholesterol) were identified in the caeca of broilers that received diets supplemented with YCs fermented for 24 or 60 hr. In summary, the different fermentation times of the YCs can markedly improve the growth performance and FCR of broilers by altering the caecal microbial community, and the growth performance which is related to the changes in key metabolic pathways.

Effects of probiotics on cecal microbiome profile altered by duck Escherichia coli 17 infection in Cherry Valley ducks

Avian colibacillosis is one of the most serious infectious bacterial diseases that endanger the modern poultry industry. Lactobacillus is believed to inhibit intestinal pathogens and maintain a healthy gut microbiota. This study aimed to investigate Lactobacillus supplementation in Cherry Valley ducks to prevent the intestinal flora dysbiosis caused by Duck Escherichia coli 17. One hundred and twenty healthy one day old Cherry Valley ducks were randomized to three study groups (Group I = the control group; Group II = duck Escherichia coli 17 challenge group and Group III = DE17 challenge group supplemented with lactic acid bacteria composite preparation). Cherry Valley ducks in Group II and Group III were gavage challenged with DE17 (1 × 10⁵ CFU/mL) on day 14. Pyrosequencing of the V3/V4 variable regions of the genes encoding for 16S rRNA was used for sequence analysis. The results showed that the normal intestinal microecology was affected by DE17, including a relative increase in proteobacteria. At the same time, the Lactobacillales were increased and harmful bacteria were decreased in different intestinal segments of ducks in Group III, compared to those in Group II. Network analysis showed that dietary lactic acid bacteria addition improved the interaction pattern within the cecal microbiota of ducks and the result showed that in Ruminococcus_2 was independently present in the group III and Lachnospiraceae_NK4A136_group species correlation existed between group I and group III. This study proved that oral supplementation with Lactobacillus casei 1.2435, Lactobacillus rhamnosus 621 and Lactobacillus rhamnosus A4 can mitigate DE17 induced intestinal flora dysbiosis.

Effects of bacteriocin and organic acid on growth performance, small intestine histomorphology, and microbiology in Japanese quails (Coturnix coturnix japonica)

In this study, 600 1-day-old Japanese quail chicks (Coturnix coturnix japonica) were used to investigate the effects of bacteriocin and organic acids on performance and intestinal histomorphology and microbiology. Chicks were allocated to 6 groups, i.e., control, Bac150 (150 mg/kg bacteriocin), Bac300 (300 mg/kg bacteriocin), OA (3 g/kg organic acid blend), Bac150+OA (150 mg/kg bacteriocin + 3 g/kg organic acid blend), and Bac300+OA (300 mg/kg bacteriocin + 3 g/kg organic acid blend) group. The trial lasted 35 days. At the end of the trial, a statistical increase was not observed in the performance parameters of chicks with feed additives. However, 300 mg/kg bacteriocin + 3 g/kg organic acid supplementation given together has been found to have more positive effects on intestinal microbiology and histomorphology (P < 0.05). Consequently, it is understood that the use of these feed additives together will achieve better results.

Effects of ammonia on intestinal microflora and productive performance of laying ducks

Atmospheric ammonia is harmful to poultry and human health. The effect of ammonia on the intestinal microflora of laying ducks is still unknown. In this study, the effects of atmospheric ammonia and exposure time on the intestinal microflora of laying ducks were investigated using 16S rDNA sequencing technology. The body weight, ovary weight, spleen weight, liver weight, and productive performance of laying ducks were also recorded, and the relationship between intestinal microflora diversity and productive performance was analyzed. The results showed that Bacteroidetes, Firmicutes, and Proteobacteria were the dominant bacterial phyla. At the phylum and genus levels, with the exception of the phylum Firmicutes and the genus Sutterella, the top 10 most abundant phyla and genera differed significantly when the ammonia concentration was increased from 10 to 75 ppm and/or the exposure time was extended from 10 to 30 D. Laying rate was highly significantly lower in ducks exposed to 75 ppm ammonia for 10 D compared with those exposed to 10 ppm ammonia for 10 D. Body, ovary, and spleen weights also decreased when the ammonia concentration was increased. At the genus level, Flavonifractor was highly significantly positively correlated with ovary weight. Methanocorpusculum and Anaerotruncus were significantly positively correlated with ovary weight. Lactobacillus was significantly positively correlated with spleen weight. Phascolarctobacterium, Sphaerochaeta, Erysipelotrichaceae_UCG.004, and Lactococcus were significantly positively correlated with spleen weight. These results indicated that ammonia affected the diversity of the intestinal microbiota and the productive performance of laying ducks. Several intestinal microbiota genera were also correlated with organ weights.

The effect of three tropical medicinal plants and superzist probiotic on growth performance, carcass characteristics, blood constitutes, immune response, and gut microflora of broiler

The pivotal aim of the present context was to determine the effect of probiotic (superzist) and medicinal plants (R. coriaria, H. persicum, and M. piperita) powder on growth performance, carcass characteristics, blood parameters, immunity response, and microflora counts of broilers over a 42-day feeding period. One hundred and fifty one-day-old chickens were randomly allocated to the following five treatments: (1) Control diets; (2) control diets + 0.03% w/v superzist; (3) control diets + 0.5% w/v R. coriaria; (4) control diets + 0.5% w/v H. persicum; and (5) control diets + 0.5% w/v M. piperita. No significant differences among treatments on broiler performance during 29th to 35th days of age, whereas a gradual reduction (P < 0.05) in the feed efficiency and economic index values between 36th to 42nd days of age, across the treatments versus control diet. Supplementations were increased (P < 0.05), the colon weight, colon length, and right cecum weight versus control. However, the superzist and phytogenic supplementation slightly increased the jejunum length, ileum length, and left cecum length. The supplementation showed reduced heterophils, increased lymphocytes and monocytes percentage, and decreased heterophils/lymphocytes ratio. Additions of superzist and medicinal plants reduced (P < 0.05) the total counts of E. coli and improved (P < 0.05) the cecal lactobacilli. In conclusion, under the appropriate conditions of this investigation, the superzist and tested medicinal plants could undoubtedly be ideal alternatives to the use of existing antibiotics as growth promoters in poultry industry.

Modulation of the gut microbiome: a systematic review of the effect of bariatric surgery

OBJECTIVE

Bariatric surgery is recommended for patients with obesity and type 2 diabetes. Recent evidence suggested a strong connection between gut microbiota and bariatric surgery.

DESIGN

Systematic review.

METHODS

The PubMed and OVID EMBASE were used, and articles concerning bariatric surgery and gut microbiota were screened. The main outcome measures were alterations of gut microbiota after bariatric surgery and correlations between gut microbiota and host metabolism. We applied the system of evidence level to evaluate the alteration of microbiota. Modulation of short-chain fatty acid and gut genetic content was also investigated.

RESULTS

Totally 12 animal experiments and 9 clinical studies were included. Based on strong evidence, 4 phyla (Bacteroidetes, Fusobacteria, Verrucomicrobia and Proteobacteria) increased after surgery; within the phylum Firmicutes, Lactobacillales and Enterococcus increased; and within the phylum Proteobacteria, Gammaproteobacteria, Enterobacteriales Enterobacteriaceae and several genera and species increased. Decreased microbial groups were Firmicutes, Clostridiales, Clostridiaceae, Blautia and Dorea. However, the change in microbial diversity is still under debate. Faecalibacterium prausnitzii, Lactobacillus and Coprococcus comes are implicated in many of the outcomes, including body composition and glucose homeostasis.

CONCLUSIONS

There is strong evidence to support a considerable alteration of the gut microbiome after bariatric surgery. Deeper investigations are required to confirm the mechanisms that link the gut microbiome and metabolic alterations in human metabolism.

Effects of dietary supplementation of Saccharomyces cerevisiae fermentation product to sows and their offspring on growth and meat quality

This study evaluated the effects of long term dietary supplementation of Saccharomyces cerevisiae fermentation product (SCFP) in the diets for sows and offspring on growth performance, intestinal morphology, volatile fatty acid production, and carcass characteristics of offspring. Newly weaned pigs (n = 256) were allotted to 4 treatments based on a 2 × 2 factorial arrangement. Each treatment had 8 pens with 8 pigs per pen. First factor was maternal dietary effects (no SCFP, or SCFP at 12.0 and 15.0 g/d through gestation and lactation, respectively) and the second factor was dietary supplementation of SCFP to offspring (no SCFP, or SCFP at 0.2 and 0.1% for nursery and finisher, respectively). Pigs were on a 6-phase feeding program with assigned diets from nursery to slaughter. Body weights (BW) and feeder weights were measured at the end of each phase. On d 5 after weaning, 1 pig per pen was euthanized to evaluate intestinal morphology and volatile fatty acid production. At 115 kg of BW, 1 pig from each pen was slaughtered to measure carcass characteristics. Feeding diets with SCFP to sows or to their offspring had no effect on BW, overall average daily gain (ADG), average daily feed intake (ADFI), and gain-to-feed (G:F) ratio during the nursery or finisher period. Feeding SCFP to sows tended to increase (P = 0.098) cecal butyric acid production in their offspring. Pigs with SCFP tended to have a greater (P = 0.084) concentration of acetic acid but a reduced (P = 0.054) propionic acid in colon digesta than pigs without SCFP regardless of maternal feeding regimen. Loin marbling scores were greater (P = 0.043) in pigs with SCFP than those without SCFP regardless of maternal feeding regimen. Overall, supplementation of SCFP in sow diets did not affect growth performance or intestinal morphology of their offspring. Supplementation of SCFP in diets of offspring from nursery to slaughter had little effect on growth performance. However, inclusion of SCFP from nursery to slaughter improved marbling score possibly by increased acetic acid and butyric acid production in the large intestine.