Effects of Lactobacillus plantarum and its Fermentation Products on Growth Performance, Immune Function, Intestinal pH and Cecal Microorganisms of Lingnan Yellow Chicken

Effects of Lactobacillus acidophilus on production performance and immunity of broiler chickens and their mechanism

Introduction

Lactobacillus species have attracted more and more attention as a potential antibiotic substitute for human health and animal production due to their remarkable antibacterial effects. However, the underlying mechanism is unclear. This experiment's goal was to investigate the impacts of lactic acid bacteria (LAB) on the growth performance, carcass characteristics, immune function of broiler chickens and their mechanism.

Methods

One hundred and eighty 1-day-old AA broilers were used and randomly allocated into 3 treatment groups with 6 replicates of 10 chickens per replicate. The 3 treatment groups were control group (CK), L. acidophilus added group (LAB-E, 1.0 × 108 CFU/kg) for the first 7 days; L. acidophilus added group (LAB-A, 1.0 × 108 CFU/kg) for the whole experimental period. Broilers had free access to water and feed.

Results

The results showed that addition of L. acidophilus for the whole experimental period significantly decreased ADFI, FCR and the abdominal fat percentage of broilers (p < 0.05), tended to increase the levels of IgG in broiler serum (p = 0.093). The LAB-A group had higher HDL-C content and IL-2, IL-4 content, and lower level of LPS in broiler serum compared to the controls (p < 0.05).

Discussion

In conclusion, L. acidophilus improved feed efficiency and immune function of broilers by controlling nutrient metabolism and inflammation responses of broilers. L. acidophilus can be used as a potential substitute for antibiotics in broiler production.

Microbiomic and Metabolomic Insights into the Mechanisms of Alfalfa Polysaccharides and Seaweed Polysaccharides in Alleviating Diarrhea in Pre-Weaning Holstein Calves

Neonatal calves' diarrhea, which can be severe enough to cause death, has a significant impact on the global cattle industry. In this study, alfalfa polysaccharides and seaweed polysaccharides were found to significantly improve the diarrhea condition in neonatal calves. To explore the underlying mechanisms, further microbiomic and metabolomic analyses were conducted. This study investigated the impact of alfalfa polysaccharides and seaweed polysaccharides on growth performance, serum metabolites, gut microbiota, and metabolomics in neonatal Holstein calves. A total of 24 newborn calves were randomly assigned to three groups, with 8 calves per treatment group. The control (CON) group was fed a basal diet, the alfalfa polysaccharide (AP) group received a basal diet supplemented with alfalfa polysaccharides (4 g/calf/day), and the seaweed polysaccharide group (SP) received a basal diet supplemented with seaweed polysaccharides (4 g/calf/day). These polysaccharides were plant extracts. Compared to the CON group, the results indicated that SP significantly enhanced the body weight, height, chest circumference, and average daily gain of Holstein calves (p < 0.05), while also reducing the diarrhea rate and improving manure scoring (p < 0.05). Compared to the CON, AP also reduced the diarrhea rate (p < 0.05). In terms of serum biochemistry, supplementation with AP and SP increased serum alkaline phosphatase (ALP) and insulin-like growth factor 1 (IGF-1) levels compared to the CON group (p < 0.05). Both AP and SP elevated serum catalase (CAT) and Total Antioxidant Capacity (T-AOC) levels, indicating enhanced antioxidant status (p < 0.05). Regarding immune responses, supplementation with AP and SP significantly increased serum complement component 3 (C3) and immunoglobulin M (IgM) levels, while significantly reducing pro-inflammatory cytokines interleukin-18 (IL-18), tumor necrosis factor alpha (TNF-α), and interferon-gamma (IFN-γ) compared to the CON group (p < 0.05). Microbiota analysis revealed that AP modulated the abundance of Firmicutes, while SP influenced the abundance of Prevotella and Succiniclasticum. AP and SP differentially influenced intestinal metabolites compared to the CON group, leading to enrichment in pathways related to immunity, antibacterial, and anti-inflammatory functions. These pathways included the biosynthesis of alkaloids from ornithine, lysine, and nicotinic acid, glucocorticoid and mineralocorticoid receptor canothersis/antagonists, secondary metabolite biosynthesis, and alkaloid biosynthesis from histidine and purine, thus alleviating intestinal inflammation. Therefore, by supplementing with AP and SP, the diarrhea rate in calves was reduced, and the immune function of Holstein calves was enhanced, while simultaneously promoting a higher relative abundance of beneficial gut bacteria and suppressing the relative abundance of pathogenic bacteria. Additionally, gut pathways associated with immune response and inflammation were modulated by AP and SP. This study provided valuable insights and theoretical underpinnings for the use of AP and SP in preventing diarrhea in neonatal calves.

Lactiplantibacillus plantarum ameliorated the negative effects of a low-protein diet on growth performance, antioxidant capacity, immune status, and gut microbiota of laying chicks

This experiment was conducted to investigate the effects of adding Lactiplantibacillus plantarum to a low-protein diet on the growth performance, ability immune status, and intestinal microbiota of 0-21-day-old layer chickens. A total of 180 one-day-old healthy Hy-line brown laying chicks were randomly divided into three groups with three replicates each of 20 chicks. The control group was fed a basal diet containing 19% protein, the low-protein (LP) group was fed a diet containing 17% protein, and the probiotic (LPL) group was fed with the 17% protein diet supplemented with L. plantarum (1.0 × 109 CFU/kg). The growth performance, antioxidant capacity, immune status, and gut microbiota of laying chickens were detected. We found that L. plantarum supplementation increased the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), total antioxidant capacity (T-AOC), and levels of immunoglobulin (Ig) A, IgG, and interleukin-10 (IL-10) in serum of 17% protein +1.0 × 109 CFU/kg L. plantarum (LPL) compared to the 19% protein group (control). Furthermore, L. plantarum supplementation increased the liver index, GSH-Px and T-AOC activity in serum, and changed the microflora structure, diversity, and polyketose unit bioanabolic metabolism of 17% protein +1.0 × 109 CFU/kg L. plantarum (LPL) compared to the 17% protein group (LP). In conclusion, L. plantarum supplementation could compensate for the adverse effects of low-protein diets in chicks, and the combination of a low-protein diet and L. plantarum is a feasible way to reduce protein in the diet.

Synbiotics effects of d-tagatose and Lactobacillus rhamnosus GG on the inflammation and oxidative stress reaction of Gallus gallus based on the genus of cecal bacteria and their metabolites

BACKGROUNDS

Abuse of feed supplement can cause oxidative stress and inflammatory responses in Gallus gallus. Synbiotics are composed of prebiotics and probiotics and it possess huge application potentials in the treatment of animal diseases.

METHODS

This study examined the effect of d-tagatose on the probiotic properties of L. rhamnosus GG, L. paracasei, and S. lactis so as to screen the best synbiotic combinations. Treat Gallus gallus exhibiting oxidative stress and immune response caused by aflatoxin b1 with optimal synbiotics for 14 days, detect the changes of inflammatory markers and oxidative stress markers of Gallus gallus using qRT-PCR, and identified the intestinal bacteria genera and their metabolites in the cecum of Gallus gallus using gut microbiota and metabolomics analysis.

RESULTS AND CONCLUSION

The results indicated that oxidative stress and immune response factor expressions quantity in Gallus gallus decreased significantly after 14 days of treatment, compared with model group, the low-dose treatment group's SOD1, SOD3, GPX1, GPX2, GSR, H6DP, and HO-1 genes in liver were downregulated by 36.03%, 40.01%, 45.86%, 40.79%, 37.68%, 25.04%, and 29.89%, the IL-1, IL-2, IL-4, IL-6, IgA, IgM, and IgG genes in blood and spleen were downregulated by 26.59%, 34.19%, 21.19%, 28.18%, 35.93%, 12.67%, 21.81 and 35.93%, 22.85%, 21.19%, 28.78%, 35.93%, 15.36%, 29.73%. The intestinal bacteria genera and metabolomics analysis results indicated that the abundance of beneficial bacteria genus was up-regulated, and the proportion of pathogenic bacteria genera decreased. The amount of beneficial metabolites associated with antioxidant and anti-inflammatory effects was upregulated. The synbiotic composed of d-tagatose and L. rhamnosus GG can treat oxidative stress and immune response by altering the structure of intestinal bacteria genera and the production of metabolites.

Characterization and functionality of Ligilactobacillus agilis 1003 isolated from chicken cecum against Klebsiella pneumoniae

Lactic acid bacteria are widely regarded as safe alternatives to antibiotics in livestock and poultry farming and have probiotic potential. Ligilactobacillus agilis (L. agilis) is a prominent component of pigeon crop microbiota; however, its function is unknown. In this study, a strain of L. agilis 1003 from pigeon cecum was identified by combining whole genome sequencing and phenotypic analysis, and its safety and probiotic properties were studied. Whole-genome sequencing revealed that the L. agilis 1003 genome length is 2.58 Mb, its average percent guanine-cytosine is 40.43%, and it encodes 1,757 protein-coding genes. Annotation of clusters of orthologous groups classified predicted proteins from the assembled genome as having cellular, metabolic, and information-related functions. A gene cluster associated with the synthesis of a broad-spectrum antimicrobial compound confirmed by antibacterial spectrum testing was identified using genome mining tools. Based on hemolysis test results, the strain was determined to be safe. This strain exhibited a high survival rate in the presence of bile salts and acidic conditions and a significant self-aggregation propensity and hydrophobicity. In vivo animal experiments showed that L. agilis 1003 exhibits probiotic and antibacterial effects and that the substances exerting antibacterial effects are organic acids. Metabolomics analysis revealed that L. agilis 1003 supernatant contained seven organic acids, including butyric acid. L. agilis 1003 showed good safety and probiotic potential in genomics, physiological biochemistry, and animal experiments, and could be considered a suitable candidate for promoting livestock and poultry health.

Characterization of the probiotic and functional properties of Enterococcus faecalis AQ10 isolated from chicken cecum

Lactic acid bacteria are considered the safest alternative to antibiotics and have a broad range of applications in animal husbandry. Enterococcus faecalis is a primary component of the chicken gut microbiota; it is known for its ability to regulate intestinal microbial balance and its probiotic functions. In this study, E. faecalis strain AQ10 from isolated from was the chicken cecum and used a combination of whole-genome sequencing and phenotypic analyses to investigate its probiotic properties. Whole-genome sequencing revealed that the genome length of E. faecalis AQ10 is 2.98 Mbp, with an average guanine-cytosine content of 38.12%, and includes 2832 protein-coding genes. Genome mining tools were used to identify an antimicrobial compound gene cluster. Additionally, E. faecalis AQ10 exhibited probiotic characteristics in vivo and antibacterial effects in vitro, with organic acids potentially contributing to its anti-Klebsiella pneumoniae activity. Metabolomics analyses revealed that the supernatant of E. faecalis AQ10 contained seven organic acids. In conclusion, E. faecalis AQ10 demonstrates significant probiotic potential and may be a suitable candidate for use in livestock and poultry breeding.

Effect of Lactobacillus paracasei LK01 on Growth Performance, Antioxidant Capacity, Immunity, Intestinal Health, and Serum Biochemical Indices in Broilers

This study aimed to investigate the effects of adding L. paracasei LK01 to the diet on the growth performance, antioxidant capacity, immunity, intestinal health, and serum biochemical indicators of broilers. This study selected 1080 one-day-old broiler chickens with similar body weight, and randomly divided them into six groups, with six replicates in each group and 30 chicks in each replicate. The chicks were fed (1) the basal diet (CON), (2) the basal diet with 106 CFU/kg L. paracasei LK01(T1), (3) the basal diet with 107 CFU/kg L. paracasei LK01(T2), (4) the basal diet with 108 CFU/kg L. paracasei LK01(T3), (5) the basal diet with 109 CFU/kg L. paracasei LK01(T4), and (6) the basal diet with 1010 CFU/kg L. paracasei LK01(T5). The experiment lasted for 42 days. In this study, compared with the CON group, the diet supplemented with L. paracasei significantly increased body weight from 1 to 21 days (p < 0.05). In addition, the 106 CFU/kg L. paracasei LK01 group significantly reduced the activity of glutamic oxaloacetic transaminase and triglyceride levels; the 107 CFU/kg,108 CFU/kg, and 109 CFU/kg L. paracasei LK01 groups also reduced serum uric acid and total cholesterol levels (p < 0.05). The experimental groups all had lower serum levels of malondialdehyde and interleukin-1β (p < 0.01). Except for the 106 CFU/kg group, all experimental groups had significantly lower tumor necrosis factor-α, and the 106 and 107 CFU/kg groups had higher immunoglobulin M levels (p < 0.05). In addition, the 106 CFU/kg group significantly reduced the depth of the ileocecal crypts and increased the villus-to-crypt ratio (V/C) of the jejunum and ileum. In addition, dietary supplementation with L. paracasei LK01 did not change the α diversity of the microbial community in the cecum, but significantly increased the proportion of Bacteroides (phylum) (p < 0.05). The 106 CFU/kg group also significantly increased the abundance of beneficial bacteria such as Ruminococcaceae (genus), Lachnospiraceae (genus), and Faecalibacterium (genus) (p < 0.05). In summary, this study revealed that adding 106 CFU/kg of L. paracasei LKO1 to broiler diets can improve their production performance, serum biochemical indicators, antioxidant, and immune capabilities, as well as cecal flora.

Gallnut tannic acid alleviates gut damage induced by Salmonella pullorum in broilers by enhancing barrier function and modulating microbiota

Pullorum disease (PD) is a bacterial infection caused by Salmonella pullorum (S. pullorum) that affects poultry. It is highly infectious and often fatal. Antibiotics are currently the mainstay of prophylactic and therapeutic treatments for PD, but their use can lead to the development of resistance in pathogenic bacteria and disruption of the host's intestinal flora. We added neomycin sulfate and different doses of tannic acid (TA) to the drinking water of chicks at 3 days of age and infected them with PD by intraperitoneal injection of S. pullorum at 9 days of age. We analyzed intestinal histopathological changes and the expression of immune-related genes and proteins by using the plate smear method, histological staining, real-time fluorescence quantitative PCR, ELISA kits, and 16S rRNA Analysis of intestinal flora. The results demonstrate that S. pullorum induces alterations in the immune status and impairs the functionality of the liver and intestinal barrier. We found that tannic acid significantly ameliorated S. pullorum-induced liver and intestinal damage, protected the intestinal physical and chemical barriers, restored the intestinal immune barrier function, and regulated the intestinal flora. Our results showed that TA has good anti-diarrhoeal, growth-promoting, immune-regulating, intestinal barrier-protecting and intestinal flora-balancing effects, and the best effect was achieved at an additive dose of 0.2%.

Effects of Dietary Terminalia chebula Extract on Growth Performance, Immune Function, Antioxidant Capacity, and Intestinal Health of Broilers

Terminalia chebula extract (TCE) has many physiological functions and is potentially helpful in maintaining poultry health, but its specific effect on the growth of broilers is not yet known. This research investigated the effects of dietary Terminalia chebula extract (TCE) supplementation on growth performance, immune function, antioxidant capacity, and intestinal health in yellow-feathered broilers. A total of 288 one-day-old yellow-feathered broilers were divided into four treatment groups (72 broilers/group), each with six replicates of 12 broilers. The broilers were given a basal diet of corn-soybean meal supplemented with 0 (control), 200, 400, and 600 mg/kg TCE for 56 d. The results demonstrated that, compared with the basal diet, the addition of TCE significantly increased (linear and quadratic, p < 0.05) the final body weight and overall weight gain and performance and decreased (linear and quadratic, p < 0.05) the feed-to-gain ratio in the overall period. Dietary TCE increased (linear, p < 0.05) the levels of IgM, IL-4, and IL-10 and decreased (linear and quadratic, p < 0.05) the level of IL-6 in the serum. Dietary TCE increased (linear and quadratic, p < 0.05) the levels of IL-2 and IL-4, decreased (linear and quadratic, p < 0.05) the level of IL-1β, and decreased (linear, p < 0.05) the level of IL-6 in the liver. Dietary TCE increased (linear and quadratic, p < 0.05) the level of IgM and IL-10, increased (linear, p < 0.05) the level of IgG, and decreased (linear and quadratic, p < 0.05) the levels of IL-1β and IL-6 in the spleen. Supplementation with TCE linearly and quadratically increased (p < 0.05) the catalase, superoxide dismutase, glutathione peroxidase, and total antioxidant capacity activities while decreasing (p < 0.05) the malonic dialdehyde concentrations in the serum, liver, and spleen. TCE-containing diets for broilers resulted in a higher (linear and quadratic, p < 0.05) villus height, a higher (linear and quadratic, p < 0.05) ratio of villus height to crypt depth, and a lower (linear and quadratic, p < 0.05) crypt depth compared with the basal diet. TCE significantly increased (linear, p < 0.05) the acetic and butyric acid concentrations and decreased (quadratic, p < 0.05) the isovaleric acid concentration. Bacteroidaceae and Bacteroides, which regulate the richness and diversity of microorganisms, were more abundant and contained when TCE was added to the diet. In conclusion, these findings demonstrate that supplementing broilers with TCE could boost their immune function, antioxidant capacity, and gut health, improving their growth performance; they could also provide a reference for future research on TCE.