Effects of dietary inulin supplementation on the composition and dynamics of cecal microbiota and growth-related parameters in broiler chickens

Effects of Supplementation with Encapsulated Different Postbiotics, Alone or with Inulin, on Growth Performance, Carcass and Organ Characteristics, Blood Parameters, Growth Hormone, and Insulin-like Growth Factor mRNA in Broilers

This study aimed to evaluate the effects of encapsulated postbiotics derived from various probiotic microorganisms, alone or in combination with inulin, on the growth performance, carcass traits, organ weights, blood parameters, and mRNA expression of selected hormones in broilers. A total of 588 one-day-old male Ross-308 chicks were randomly designated to six replicates of seven dietary treatments (initial body weight: 40.85 ± 0.56 g, per replicate, n = 14 chicks). The treatments consisted of a basal diet (C), supplemented with encapsulated postbiotics (0.30%) derived from Lactobacillus plantarum (ELP), Bacillus subtilis (EBS), or Enterococcus faecium (EEF), as well as combinations of these encapsulated postbiotics with 1.0% inulin (ELPI, EBSI, and EEFI) for six weeks. The results demonstrated that the body weight and body weight gain of birds that were fed diets supplemented with encapsulated postbiotics or their combinations with inulin significantly increased in comparison to the C group (p < 0.001). Feed intake (FI) remained unaffected during days 1-21, as did feed conversion ratios (FCR) during days 22-42, and days 1-42 demonstrated no significant differences (p > 0.05). However, FCR improved during days 1-21, and FI increased during days 22-42 and 1-42 (p < 0.05). Carcass yield, including breast, thigh, and abdominal fat yields, was enhanced (p < 0.001). Although the relative weights of the heart, spleen, pancreas, and liver were unaffected (p > 0.05), the relative weight of the bursa of Fabricius increased (p < 0.001). Serum antioxidant status and immunoglobulin A and M levels were higher, while liver enzymes, cholesterol, triglycerides, and total oxidant status were lower in the supplemented groups compared to the control group (p < 0.001). Serum glucose and protein levels remained unchanged (p > 0.05). The mRNA expression of growth hormone and insulin-like growth factor was upregulated in the supplemented groups (p < 0.001). In conclusion, encapsulated postbiotics (0.30%) derived from different probiotics, alone or combined with inulin (1.0%), positively influenced growth performance, carcass traits, and immunity in male broilers.

Effects of Dietary Supplementation Using Phytobiotics with Different Functional Properties on Expression of Immunity Genes, Intestinal Histology, Growth, and Meat Productivity of Broiler Chickens

The aim of this study was to investigate the expression of immunity-related genes and morpho-histological features of the intestines, and the growth and meat production of broiler chickens when fed plant extracts with different functional components. Chickens in the control group received a basic diet. The feed in the experimental groups contained plant extracts standardized to various biologically active components such as the extract of common chicory with inulin (INUL), St. John's wort with flavonoids (FLAV), maral root with ecdysterone (ECDS), and extracts of creeping thyme with flavonoids and tannins (FLAV-TANN). The results of this study showed that the application of the studied phytobiotics increased the expression of the pro-inflammatory gene IL8, with the 2-ΔΔCT value ranging from 2.66 to 4.63. In the case of the antimicrobial peptide gene AvBD9, the 2-ΔΔCT value ranged from 1.66 to 8.16, depending on the group. AvBD10 gene expression increased (2-ΔΔCT = 2.19) when the chickens were fed the chicory extract and decreased when thyme extract was used (2-ΔΔCT = 0.33). The study also found that using biologically active components in the diets of broiler chickens was accompanied by a significant decrease in the height of epithelial cells in the cecum mucous membrane in the INUL group (61.3%, p ≤ 0.001), FLAV group (60.0%, p ≤ 0.001), ECDS group (48.2%, p ≤ 0.001), and FLAV + TANN group (67.6%, p ≤ 0.001). It also caused a reduction in the depth of crypts in the INUL (38.4%, p ≤ 0.001), FLAV (32.3%, p ≤ 0.001), ECDS (50.9%, p ≤ 0.001), and FLAV + TANN (53.4%, p ≤ 0.001) groups. The use of all extracts, except creeping thyme, caused changes in the size of muscular elements in the intestinal walls; thus, the thickness of the muscular layer increased 1.5-2.0 times under the influence of flavonoids in St. John's wort and of inulin in chicory, to 430.99 and 579.87 μm, respectively (p ≤ 0.001), and decreased 1.9 times under the influence of ecdysterone in maral root to 151.59 μm (p ≤ 0.001). The use of phytobiotics increased feed consumption and stock safety, leading to an increase of 4.1-7.5% in the live weights of broiler chickens at the end of the rearing period, thus contributing to the higher slaughter quality of poultry; in particular, the weights of breast muscles in cockerels in the INUL group increased by 16.9% (p ≤ 0.05), while the weights in the ECDS and FLAV + TANN groups increased by 18.1% (p ≤ 0.05) and 23.1% (p ≤ 0.01), respectively. Thus, the use of the studied phytobiotics in the broiler chicken diet increases meat production and activates immunity, which indicates the possibility of replacing antibacterial drugs with natural nutraceuticals.

Effect of fructo-oligosaccharides on growth performance and meat quality in broilers

This study investigated the fructo-oligosaccharides (FOS) on growth performance and meat quality in broilers. Total 160 Xianghuang broilers aged 2 months were randomly assigned into 2 groups, CON (control), FOS (supplemented 0.5% fructo-oligosaccharides in diet). After 38 days, the breast, thigh muscle and liver samples were collected for further analysis. Results showed that no significant effect of 0.5% FOS on growth performance such as average daily gain (ADG), average daily feed intake (ADFI) or feed-to-gain ratio (F:G) were observed (P > 0.05). Broilers in FOS group had a yellower breast than that in CON group (P < 0.05). Breast pH45min and thigh pH24h value of FOS group were greater than that in CON group (P < 0.05). Max shear force and work of shear of cooked breast (pectoralis major) muscle was lower in FOS group compared with CON group (P < 0.05). Hardness (P = 0.065), fracturability (P = 0.063), gumminess (P = 0.079), chewiness (P = 0.080) of cooked thigh meat tended to be higher in FOS group compared to the CON group. Addition of 0.5% FOS resulted in lower thigh total superoxide dismutase (T-SOD) activity compared to CON group (P < 0.05). The malonaldehyde (MDA) concentration (P = 0.066) of breast muscle tended to be lower in FOS group compared with CON group. There was an increasing trend for total antioxidant capacity (T-AOC) activity of thigh muscle in FOS group compared to CON group (P = 0.053). Relative mRNA expression of breast catalase (CAT), superoxide dismutase 1 (SOD1), thioredoxin reductase 1 (TXNRD) were up-regulated by FOS supplementation compared with CON group (P < 0.05). In conclusion, FOS can be utilized at 0.5 % to improve meat quality such as elevating pH value, yellowness and decreasing max shear force of muscle through enhancing the antioxidant activity in broilers.

Dietary metabolizable energy and crude protein levels affect Taihe silky fowl growth performance, meat quality, and cecal microbiota during fattening

The effects of dietary metabolizable energy (ME) and crude protein (CP) on the growth performance, meat quality, and cecal microbiota of Taihe Silky Fowl (TSF) during fattening were investigated. In total, 900 twelve-week-old female fowl were randomly allocated to 9 treatments (5 replicates per group, 20 fowl per replicate), and were fed a 3 × 3 factorial arrangement of treatments diets (ME: 11.30, 11.93, or 12.56 MJ/kg; CP: 15%, 16%, or 17%). As ME increased, the average daily feed intake (ADFI, P<0.001), feed conversion ratio (FCR, P<0.001), pectoral and thigh shear forces (P<0.05), pectoral and thigh muscle fiber diameter (P<0.001) decreased significantly, while muscle fiber density increased (P<0.001). Pectoral muscle fiber diameter was lower and muscle fiber density higher at 16% CP than 15% or 17%. As ME increased, pectoral crude fat content increased significantly (P = 0.007). Pectoral crude protein, total amino acid (TAA), and essential amino acid (EAA) content were higher at 15% dietary CP than 16% or 17%. As ME increased, pectoral inosine monophosphate (IMP, P = 0.006), uridylic monophosphate (UMP, P = 0.003), guanylic monophosphate (GMP, P = 0.009), and adenosine monophosphate (AMP, P <0.001) decreased significantly, while hypoxanthine riboside (HxR, P = 0.045) increased. As dietary CP increased, IMP (P = 0.019), AMP (P <0.001), and HxR (P = 0.024) increased significantly. Cecal microbiota composition varied with dietary ME: 12.56 MJ/kg ME increased the abundance of Bifidobacteriaceae, and 15% CP increased that of Paraprevotella. These findings suggest that 12.56 MJ/kg dietary ME and 15% CP can enhance growth performance, improve meat quality by reducing shear force, enhancing flavor and nutritional value, and benefit for intestinal microbiota in fattening TSF.

Research advancements on the diversity and host interaction of gut microbiota in chickens

The maintenance of host health and immune function is heavily dependent on the gut microbiota. However, the precise contribution of individual microbial taxa to regulating the overall functionality of the gut microbiome remains inadequately investigated. Chickens are commonly used as models for studying poultry gut microbiota, with high-throughput 16S rRNA sequencing has emerged as a valuable tool for assessing both its composition and functionality. The interactions between the gut's microbial community and its host significantly influence health outcomes, disease susceptibility, and various mechanisms affecting gastrointestinal function. Despite substantial research efforts, the dynamic nature of this microbial ecosystem has led to inconsistencies in findings related to chicken gut microbiota, which is largely attributed to variations in rearing conditions. Consequently, the interaction between the chickens' gut microflora and its host remains inadequately explored. This review highlights recent advances in understanding these relationships, with a specific focus on microbial composition, diversity, functional mechanisms, and their potential implications for improving poultry production.

Expression of Genes Related to Meat Productivity, Metabolic and Morphological Significance of Broiler Chickens with the Use of Nutritional Phytochemicals

The study aimed to analyze gene expression linked to skeletal muscle growth and lipid metabolism in broiler chickens fed with plant extracts. Five groups of chickens were formed: four experimental groups and one control group. The diets of the experimental groups were supplemented with different plant extracts: chicory, St. John's wort, maral root, and creeping thyme, whereas the control group received feed without phytobiotic compounds. Weekly weighings were conducted (n = 36). The chickens were slaughtered at day 26 for tissue sampling of four birds from each group. Gene expression (MYOG, MSTN, FASN) related to muscle growth and fatty acid synthesis was analyzed using the β-actin ACTB gene as a reference. Blood samples were taken at day 35 for biochemical analysis and anatomical dissection was performed. The study revealed that using plant extracts from chicory, thyme, and maral root increased MYOG gene activity by 4.21, 7.45, and 8.93 times, respectively. T. serpyllum extract boosted the MSTN gene by 10.93 times, impacting muscle growth regulation. FASN gene expression for fatty acid synthesis increased significantly by 18.22-184.12 times with plant extracts. The best results regarding meat productivity of chickens were obtained when using R. carthamoides extract. The results of the study will serve as a basis for further development of a phytocomposition designed to increase the meat productivity of broiler chickens in the production of environmentally safe poultry products.

Effect of dietary supplementation of two fiber sources differing on fermentability and hydration capacity on performance, nutrient digestibility and cecal fermentation in broilers from 1 to 42 d of age

A total of 378 Cobb-500 male broilers were used to evaluate the effects of 2 fiber sources, differing in hydration capacity and fermentability, on gastrointestinal tract development, apparent ileal digestibility and performance from 1 to 42d of age. There were 9 replicates per each of the 3 dietary treatments, all in mash form: a wheat-soybean control (CON) diet, CON diet diluted with 1.5% of wood lignocellulose (LC diet) as a non-fermentable insoluble fiber with high hydration capacity; and CON diluted with 1.5% of a mixture of fibers (ISFC diet) containing both lignified insoluble fiber and a prebiotic soluble fiber fraction from fructooligosaccharides. Additionally, the fermentability of both fiber sources (LC and ISFC) was determined by in vitro using cecal inoculum from broilers fed the experimental diets. Both LC and ISFC treatments impaired by 4% feed conversion ratio only during the first 7d (P = 0.003) compared with CON group. In the grower period (21-42d), the ISFC group showed the best growth (P = 0.039), and at 42d tended to show the highest body weight (P = 0.095). This agrees well with the highest ileal dry matter (P = 0.033) and organic matter (P = 0.043) digestibility observed in ISFC group and the similar trend observed for ileal protein digestibility (P = 0.099) at 42d. Also, at 42 d, absolute and relative (% body weight) digestive tract weights (P ≤ 0.041) and empty gizzard weights (P ≤ 0.034) were greater for LC and ISFC groups compared to CON. The cecal molar proportion of valeratewas greatest in ISFC group (P = 0.039). In vitro gas production was higher for ISFC than for LC substrate when using either a diet-adapted or non-adapted cecal inoculum (P < 0.05). These results show the interest in combining IF with prebiotic highly fermentable fiber, such as fructooligosaccharides, in broilers to improve nutrient digestibility and finishing performance.

Inulin Supplementation Alleviates Ochratoxin A-Induced Kidney Injury through Modulating Intestinal Microbiota

Ochratoxin A (OTA) is a prevalent mycotoxin found in feed that causes significant kidney injury in animals. Further investigation was needed to devise strategies for treating OTA-induced kidney damage through the gut-kidney axis. Evidence indicates the crucial role of intestinal microbiota in kidney damage development. Inulin, a dietary fiber, protects kidneys by modulating intestinal microbiota and promoting short-chain fatty acid (SCFA) production. However, its precise mechanism in OTA-induced kidney damage remained unclear. In this study, chickens were orally administered OTA and inulin for 2 weeks to investigate inulin's effects on OTA-induced kidney damage and underlying mechanisms. The alteration of intestinal microbiota, SCFAs contents, and SCFA receptors was further analyzed. Results demonstrated that inulin supplementation influenced intestinal microbiota, increased SCFAs production, and mitigated OTA-induced kidney damage in chickens. The importance of microbiota in mediating inulin's renal protection was further confirmed by antibiotic and fecal microbiota transplantation experiments. Additionally, inulin exhibited antioxidant and anti-inflammatory properties, alleviating NLRP3 inflammasome activation and pyroptosis. In summary, inulin protected chickens from OTA-induced kidney damage, which might provide a potential strategy to mitigate the harmful effects of mycotoxins through prebiotics and safeguard renal health.

The effect and potential mechanism of inulin combined with fecal microbiota transplantation on early intestinal immune function in chicks

Our previous research found that fecal microbiota transplantation (FMT) and inulin synergistically affected the intestinal barrier and immune system function in chicks. However, does it promote the early immunity of the poultry gut-associated lymphoid tissue (GALT)? How does it regulate the immunity? We evaluated immune-related indicators in the serum, cecal tonsil, and intestine to determine whether FMT synergistic inulin had a stronger impact on gut health and which gene expression regulation was affected. The results showed that FMT synergistic inulin increased TGF-β secretion and intestinal goblet cell number and MUC2 expression on day 14. Expression of BAFFR, PAX5, CXCL12, and IL-2 on day 7 and expression of CXCR4 and IL-2 on day 14 in the cecal tonsils significantly increased. The transcriptome indicated that CD28 and CTLA4 were important regulatory factors in intestinal immunity. Correlation analysis showed that differential genes were related to the immunity and development of the gut and cecal tonsil. FMT synergistic inulin promoted the development of GALT, which improved the early-stage immunity of the intestine by regulating CD28 and CTLA4. This provided new measures for replacing antibiotic use and reducing the use of therapeutic drugs while laying a technical foundation for achieving anti-antibiotic production of poultry products.

Modulation of cyclophosphamide-induced immunosuppression and intestinal flora in broiler by deep eutectic solvent extracted polysaccharides of Acanthopanax senticosus

Introduction

The aim of this experiment was to investigate the modulation effect of Acanthopanax senticosus polysaccharide (ASPS-PD) extracted with deep eutectic solvent on cyclophosphamide-induced immunosuppression in broilers and its modulation of the gut microbiota of broilers.

Methods

The 108 one-day-old broilers were divided into six groups, including the control group, the Cyclophosphamide (CY) model group, the ASPS-PD control group, the ASPA-PD high and low dose groups and the Astragalus polysaccharide group. Body weight, feed intake, feed conversion ratio, and immune organ index of broilers at 7, 14, and 21 days were determined; IL-2, IFN-γ, and lgG1 levels were determined by enzyme-linked immunosorbent assay (ELISA); Broiler caeca feces were analyzed by amplification and 16S rRNA sequencing.

Results

The results showed that ASPS-PD can restore growth performance, increase immune organ index and improve serum cytokine levels of IL-2 and IFN-γ and immunoglobulin lgG1 levels in CY-treated broilers. The analysis of cecum flora showed that ASPS-PD can promote the proliferation of beneficial bacteria and reduce the number of harmful bacteria, regulating intestinal flora.

Discussion

Therefore, ASPA-PD may be a potential novel immunomodulator to ameliorate CY-induced immunosuppression and intestinal flora dysregulation in broiler.

Effects of prebiotics and precision biotics on performance, animal welfare and environmental impact. A review

This review aims to analyze the recent studies about prebiotics and precision biotics, as alternatives to animal growth promoters. These substances improve intestinal health, growth performance and poultry environmental impact. Prebiotics are insoluble fibers, that have no nutritive value, but they promote the growth of positive bacteria, increase the nutrients absorption and modulate the immune response. Instead, precision biotics are carbohydrates with glycosidic linkages, which interact with gut bacteria metabolism, reducing the excretion of nitrogen and consequentially, the poultry environmental impact. In the last years, different studies were published in this field, and for this reason, it is necessary to organize the results found. It was shown that mannan-oligosaccharides and β-glucans increase ileal nutrient digestibility, nitrogen retention and antibodies titers. Inulin, arabinoxylans-derived oligosaccharides, and galacto-oligosaccharides improved intestinal morphology, arranging for a larger absorption surface area. It was reported that prebiotics enhance the colonization of positive bacteria and can reduce the count of Campylobacter colonies. Furthermore, xylo-oligosaccharides are often used in animal feed, due to their ability to form organic acids, which decompose noxious substances, improving litter quality, and consequentially, reducing the environmental impact. Litter quality is a relevant aspect for ammonia emissions and for animal welfare. Whether the litter quality is poor, footpad dermatitis increase, worsening animal welfare and increasing nitrogen emissions to air. Precision biotics select metabolic pathways to modulate amino acid degradation, reintegrating the nitrogen discarded, and reducing the ammonia level in litter. It was also reported an improvement of growth performance and a better animal welfare. In conclusion, prebiotics and precision biotics can have positive effects on animal performance and welfare, and they can be a new strategy to reduce the environmental impact of chickens' farms.

Lactiplantibacillus plantarum, lactiplantibacillus pentosus and inulin meal inclusion boost the metagenomic function of broiler chickens

BACKGROUND

The inclusion of alternative ingredients in poultry feed is foreseen to impact poultry gut microbiota. New feeding strategies (probiotics/prebiotics) must be adopted to allow sustainable productions. Therefore, the current study aimed to use metagenomics approaches to determine how dietary inclusion of prebiotic (inulin) plus a multi-strain probiotic mixture of Lactiplantibacillus plantarum and Lactiplantibacillus pentosus affected microbiota composition and functions of the gastro-intestinal tract of the broilers during production. Fecal samples were collected at the beginning of the trial and after 5, 11 and 32 days for metataxonomic analysis. At the end of the trial, broilers were submitted to anatomo-pathological investigations and caecal content was subjected to volatilome analysis and DNAseq.

RESULTS

Probiotic plus prebiotic inclusion did not significantly influence bird performance and did not produce histopathological alterations or changes in blood measurements, which indicates that the probiotic did not impair the overall health status of the birds. The multi-strain probiotic plus inulin inclusion in broilers increased the abundance of Blautia, Faecalibacterium and Lachnospiraceae and as a consequence an increased level of butyric acid was observed. In addition, the administration of probiotics plus inulin modified the gut microbiota composition also at strain level since probiotics alone or in combination with inulin select specific Faecalibacterium prausnitzi strain populations. The metagenomic analysis showed in probiotic plus prebiotic fed broilers a higher number of genes required for branched-chain amino acid biosynthesis belonging to selected F. prausnitzi strains, which are crucial in increasing immune function resistance to pathogens. In the presence of the probiotic/prebiotic a reduction in the occurrence of antibiotic resistance genes belonging to aminoglycoside, beta-lactamase and lincosamide family was observed.

CONCLUSIONS

The positive microbiome modulation observed is particularly relevant, since the use of these alternative ingredients could promote a healthier status of the broiler's gut.

Effects of Major Families of Modulators on Performances and Gastrointestinal Microbiota of Poultry, Pigs and Ruminants: A Systematic Approach

Considering the ban on the use of antibiotics as growth stimulators in the livestock industry, the use of microbiota modulators appears to be an alternative solution to improve animal performance. This review aims to describe the effect of different families of modulators on the gastrointestinal microbiota of poultry, pigs and ruminants and their consequences on host physiology. To this end, 65, 32 and 4 controlled trials or systematic reviews were selected from PubMed for poultry, pigs and ruminants, respectively. Microorganisms and their derivatives were the most studied modulator family in poultry, while in pigs, the micronutrient family was the most investigated. With only four controlled trials selected for ruminants, it was difficult to conclude on the modulators of interest for this species. For some modulators, most studies showed a beneficial effect on both the phenotype and the microbiota. This was the case for probiotics and plants in poultry and minerals and probiotics in pigs. These modulators seem to be a good way for improving animal performance.

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.

Antibiotics in avian care and husbandry-status and alternative antimicrobials

Undoubtedly, the discovery of antibiotics was one of the greatest milestones in the treatment of human and animal diseases. Due to their over-use mainly as antibiotic growth promoters (AGP) in livestock farming, antimicrobial resistance has been reported with increasing intensity, especially in the last decades. In order to reduce the scale of this phenomenon, initially in the Scandinavian countries and then throughout the entire European Union, a total ban on the use of AGP was introduced, moreover, a significant limitation in the use of these feed additives is now observed almost all over the world. The withdrawal of AGP from widespread use has prompted investigators to search for alternative strategies to maintain and stabilize the composition of the gut microbiota. These strategies include substances that are used in an attempt to stimulate the growth and activity of symbiotic bacteria living in the digestive tract of animals, as well as living microorganisms capable of colonizing the host’s gastrointestinal tract, which can positively affect the composition of the intestinal microbiota by exerting a number of pro-health effects, i.e., prebiotics and probiotics, respectively. In this review we also focused on plants/herbs derived products that are collectively known as phytobiotic.

Effect of dietary supplementation of Jerusalem Artichoke extract on performance, blood biochemistry, antioxidant parameters, and immune response of growing Japanese quail

This study aimed to examine the impact of the Jerusalem Artichoke extract (JAEx) as a feed additive on the performance, blood biochemistry, antioxidant indices, immunity, and intestinal microbiota in growing Japanese quails. In total, 270 birds were randomly divided into three groups, with six replicates of 15 birds each. The first group was fed a control diet without JAEx. The second and third groups received the control diet plus 200 and 400 ppm JAEx, respectively. The groups fed the diet containing 200 and 400 ppm JAEx had the best body weight, body weight gain and feed conversion ratio, and faster growth rate with the best performance index, compared with the control group (p < 0.05). The control quails had a lower feed intake than the JAEx-treated quails. The groups fed JAEx 200 and 400 ppm had the lowest lipid profile, blood glucose, liver enzymes, Salmonella and Escherichia coli population and the highest antioxidant indices, immune responses and Lactobacilli population number compared to the control group (p < 0.05). In conclusion, the addition of JAEx at 400 ppm followed by 200 ppm improved the productive performance, antioxidant capacity, blood biochemical and immunological indices, and intestinal microbiota in growing Japanese quails.

Chicken jejunal microbiota improves growth performance by mitigating intestinal inflammation

BACKGROUND

Intestinal inflammation is prevalent in chicken, which results in decreased growth performance and considerable economic losses. Accumulated findings established the close relationship between gut microbiota and chicken growth performance. However, whether gut microbiota impacts chicken growth performance by lessening intestinal inflammation remains elusive.

RESULTS

Seven-weeks-old male and female chickens with the highest or lowest body weights were significantly different in breast and leg muscle indices and average cross-sectional area of muscle cells. 16S rRNA gene sequencing indicated Gram-positive bacteria, such as Lactobacilli, were the predominant species in high body weight chickens. Conversely, Gram-negative bacteria, such as Comamonas, Acinetobacter, Brucella, Escherichia-Shigella, Thermus, Undibacterium, and Allorhizobium-Neorhizobium-Pararhizobium-Rhizobium were significantly abundant in low body weight chickens. Serum lipopolysaccharide (LPS) level was significantly higher in low body weight chickens (101.58 ± 5.78 ng/mL) compared with high body weight chickens (85.12 ± 4.79 ng/mL). The expression of TLR4, NF-κB, MyD88, and related inflammatory cytokines in the jejunum was significantly upregulated in low body weight chickens, which led to the damage of gut barrier integrity. Furthermore, transferring fecal microbiota from adult chickens with high body weight into 1-day-old chicks reshaped the jejunal microbiota, mitigated inflammatory response, and improved chicken growth performance.

CONCLUSIONS

Our findings suggested that jejunal microbiota could affect chicken growth performance by mitigating intestinal inflammation. Video Abstract.

Plant-Derived Polysaccharides Regulated Immune Status, Gut Health and Microbiota of Broilers: A Review

In modern intensive breeding system, broilers are exposed to various challenges, such as diet changes and pathological environment, which may cause the increase in the incidence rate and even death. It is necessary to take measures to prevent diseases and maintain optimal health and productivity of broilers. With the forbidden use of antibiotics in animal feed, polysaccharides from plants have attracted much attention owing to their lower toxicity, lower drug resistance, fewer side effects, and broad-spectrum antibacterial activity. It had been demonstrated that polysaccharides derived from plant exerted various functions, such as growth promotion, anti-inflammation, maintaining the integrity of intestinal mucosa, and regulation of intestinal microbiota. Therefore, the current review aimed to provide an overview of the recent advances in the impacts of plant-derived polysaccharides on anti-inflammation, gut health, and intestinal microbiota community of broilers in order to provide a reference for further study on maintaining the integrity of intestinal structure and function, and the related mechanism involved in the polysaccharide administration intervention.

Dietary Inulin Supplementation Modulates Short-Chain Fatty Acid Levels and Cecum Microbiota Composition and Function in Chickens Infected With Salmonella

The current study investigated the effects of inulin on the gut microbiota, microbiome functions, and short-chain fatty acids (SCFAs) levels in specific pathogen-free (SPF) chickens infected with Salmonella enteritidis (SE). SPF Arbor Acres chickens (n = 240, 1-day-old) were divided into four groups: a control group (CON) fed a basal diet without inulin supplementation or SE infection, and three groups fed a basal diet supplemented with inulin 0, 0.5, and 1% (SE, 0.5%InSE, 1%InSE, respectively) up to 28-days-old, followed by SE challenge at 28 days of age. Cecal SCFA contents and microbiome composition and function were analyzed at 1-day post-infection. The results showed that SE infection significantly decreased cecal butyrate concentrations compared with the CON group (p < 0.05), while inulin supplementation reversed these changes compared with the SE group (p < 0.05). Inulin supplementation at 1% significantly increased the abundances of Lactobacillus and Streptococcus, and significantly decreased the abundances of Subdoligranulum and Sellimonas compared with the SE group (p < 0.05). The functional profiles of microbial communities based on metagenomic sequencing analysis showed that SE infection significantly increased the abundances of pathways related to carbohydrate metabolism, amino acid metabolism, energy metabolism, metabolism of cofactors and vitamins, and glycan biosynthesis and metabolism (p < 0.05), and significantly decreased the abundances of pathways related to nucleotide metabolism, translation, and replication and repair compared with the CON group (p < 0.05), and these effects were reversed by inulin supplementation (0.5 and 1%) (p < 0.05). In conclusion, inulin modulated the dysbiosis induced by SE infection via affecting SCFA metabolism and microbial functional profiles.

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.

Effects of grazing mixed-grass pastures on growth performance, immune responses, and intestinal microbiota in free-range Beijing-you chickens

There is an increasing interest in free-range poultry with the increasing focus on food safety and animal welfare. This study was conducted to evaluate the effects of grazing mixed-grass pastures on growth performance, immune responses, and intestinal microbiota in free-range laying chickens. Ten-week-old female Beijing-you chickens were blocked by the BW and randomly assigned to 3 free-range systems in poplar plantations for 120 d: forage-removed paddocks with a high stocking density of 5 m²/hen (control [CK]); mixed-grass pastures with a low stocking density of 6 m²/hen ;or mixed-grass pastures with a high stocking density of 5 m²/hen. Intestinal microbial community analysis was performed by 16S rRNA gene sequencing using Illumina MiSeq. The results revealed that no differences (P > 0.05) were found between the 3 raising systems for the BW and ADG. Chickens grazing mixed-grass pastures exhibited decreased (P > 0.05) mortality and improved immune responses as evidenced by increased T-lymphocyte proliferation (P > 0.05) and immunoglobulin A (P > 0.05) and immunoglobulin M concentrations (P < 0.05) compared with those raised in forage-removed paddocks. Metagenomic analysis indicated that grazing mixed-grass pastures regulated the intestinal microbiota by increasing the prevalence of beneficial bacteria, such as Lactobacillus, Bacteroides, and Faecalibacterium, and reducing potentially pathogenic bacteria population, such as the Rikenellaceae_RC9_gut_group compared with the CK. Therefore, this study indicated that grazing mixed-grass pastures could positively influence intestinal microbiota that may contribute to the overall growth and immunity of free-range chickens and that a low stocking density of 6 m²/hen was optimal to Beijing-you chickens grazing mixed-grass pastures.

Gut Microbiota, Blood Metabolites, and Spleen Immunity in Broiler Chickens Fed Berry Pomaces and Phenolic-Enriched Extractives

This study evaluated the performance, gut microbiota, and blood metabolites in broiler chickens fed cranberry and blueberry products for 30 days. A total of 2,800 male day-old broiler Cobb-500 chicks were randomly distributed between 10 diets: control basal diet; basal diet with bacitracin (BACI); four basal diets with 1 and 2% of cranberry (CP1, CP2) and blueberry (BP1, BP2) pomaces; and four basal diets supplemented with ethanolic extracts of cranberry (COH150, COH300) or blueberry (BOH150, BOH300) pomaces. All groups were composed of seven replicates (40 birds per replicate). Cecal and cloacal samples were collected for bacterial counts and 16S rRNA gene sequencing. Blood samples and spleens were analyzed for blood metabolites and gene expressions, respectively. The supplementation of COH300 and BOH300 significantly increased the body weight (BW) during the starting and growing phases, respectively, while COH150 improved (P < 0.05) the overall cumulated feed efficiency (FE) compared to control. The lowest prevalence (P = 0.01) of necrotic enteritis was observed with CP1 and BP1 compared to BACI and control. Cranberry pomace significantly increased the quinic acid level in blood plasma compared to other treatments. At days 21 and 28 of age, the lowest (P < 0.05) levels of triglyceride and alanine aminotransferase were observed in cranberry pomace and blueberry product-fed birds, respectively suggesting that berry feeding influenced the lipid metabolism and serum enzyme levels. The highest relative abundance of Lactobacillaceae was found in ceca of birds fed CP2 (P < 0.05). In the cloaca, BOH300 significantly (P < 0.005) increased the abundances of Acidobacteria and Lactobacillaceae. Actinobacteria showed a significant (P < 0.05) negative correlation with feed intake (FI) and FE in COH300-treated birds, whereas Proteobacteria positively correlated with the BW but negatively correlated with FI and FE, during the growing phase. In the spleen, cranberry products did not induce the release of any pro-inflammatory cytokines but upregulated the expression of several genes (IL4, IL5, CSF2, and HMBS) involved in adaptive immune responses in broilers. This study demonstrated that feed supplementation with berry products could promote the intestinal health by modulating the dynamics of the gut microbiota while influencing the metabolism in broilers.