Impact of Feeding Postbiotics and Paraprobiotics Produced From Lactiplantibacillus plantarum on Colon Mucosa Microbiota in Broiler Chickens

Microbiota but not immune modulation by a pro- and postbiotic was associated with the diet-additive interaction in broilers

This study investigated the diet-additive interactions of a Lactobacilli-based probiotic (Pro) and postbiotic (Post) on immune parameters and cecal microbiota composition, with subsequent effects on the metabolome in broilers. A completely randomized block design was employed with 2 diets [standard (SD), and challenge (CD)] and 3 additive conditions (Control, Pro, Post) involving 1,368 one-day-old male Ross 308 broilers equally distributed among 36 pens in a 42 d study. Diets were formulated to contain identical nutrient levels, with CD higher than SD in non-starch polysaccharide content by including rye and barley. Total non-specific serum Ig A, M and G concentrations were determined weekly from d14 to 35. Following vaccination, titres of specific antibodies binding Newcastle disease virus (NDV) and infectious bursal disease virus (IBDV) were measured. Microbiota composition was analyzed by 16S rRNA gene sequencing at d14 and 35, and α- and β-diversity indexes (Observed, Chao1, Bray, Jaccard) were calculated. Cecal short-chain fatty acids and the semi-polar metabolome were determined in the Control SD and all CD groups at d35. At d35, a diet-additive interaction was observed on cecal microbiota composition. Within SD, Pro and Post did not affect operational taxonomic units (OTU) abundance (adjusted-P > 0.05) and diversity indexes (P > 0.05). Within CD, Pro and Post affected the relative abundances of 37 and 44 OTUs, respectively (adjusted-P < 0.05), with Post but not Pro affecting β-diversity indexes (P = 0.041 and 0.064 for Bray and Jaccard, respectively). Within CD, Post increased cecal acetate (21%; P = 0.007) and butyrate (41%; P = 0.002) concentration and affected the concentration of 2 metabolites (adjusted-P < 0.05), while Pro affected 240 metabolites (adjusted-P < 0.05). No diet-additive interactions were observed on serum Ig (P > 0.05), except for IgM at d14 (P = 0.004). Diet composition, but not the additives, affected immune status parameters. The Pro and Post affected cecal microbiota composition only under dietary challenging conditions as previously reported for growth.

Postbiotic nanoparticles (postbiotics-NPs): a novel strategy for providing probiotics' health advantages through food consumption

In recent years, the term "postbiotics" has become increasingly popular in food microbiology, food science, and commercial products. This importance has been raised due to the safety issues associated with live bacterial cells. Postbiotics are defined as bioactive substances of probiotics. It confers unique health-promoting functions with its chemical structure, safe profile, and long shelf life. Meanwhile, postbiotics nanoparticles (postbiotics-NPs) can be considered novel postbiotic delivery systems to deliver bioactive components with health benefits and therapeutic aims, promote the shelf-life of food products, and develop novel functional foods. The present scientific literature shows that nanotechnology approaches are not yet mature enough to be used in postbiotic delivery systems. For all of that, the potential applications of postbiotics-NPs in the food industry and biomedical fields will be a new trend in the future.

Lactiplantibacillus plantarum postbiotic protects against Salmonella infection in broilers via modulating NLRP3 inflammasome and gut microbiota

Salmonella infection is a major concern in poultry production which poses potential risks to food safety. Our previous study confirmed that Lactiplantibacillus plantarum (LP) postbiotic exhibited a strong antibacterial capacity on Salmonella in vitro. This study aimed to investigate the beneficial effects and underlying mechanism of LP postbiotic on Salmonella-challenged broilers. A total of 240 one-day-old male yellow-feathered broilers were pretreated with 0.8% deMan Rogosa Sharpe (MRS) medium or 0.8% LP postbiotic (LP cell-free culture supernatant, LPC) in drinking water for 28 d, and then challenged with 1×109 CFU Salmonella enterica serovar Enteritidis (SE). Birds were sacrificed 3 d postinfection. Results showed that LPC maintained the growth performance by increasing body weight (BW), average daily gain (ADG), and average daily feed intake (ADFI) in broilers under SE challenge. LPC significantly attenuated SE-induced intestinal mucosal damage. Specifically, it decreased the intestinal injury score, increased villus length and villus/crypt, regulated the expression of intestinal injury-related genes (Villin, matrix metallopeptidase 3 [MMP3], intestinal fatty acid-binding protein [I-FABP]), and enhanced tight junctions (zona occludens-1 [ZO-1] and Claudin-1). SE infection caused a dramatic inflammatory response, as indicated by the up-regulated concentrations of interleukin (IL)-1β, IL-6, TNF-α, and the downregulation of IL-10, while LPC pretreatment markedly reversed this trend. We then found that LPC inhibited the activation of NOD-like receptor thermal protein domain associated protein 3 (NLRP3) inflammasome by decreasing the gene expression of Caspase-1, IL-lβ, and IL-18. Furthermore, LPC suppressed NLRP3 inflammasome activation by inhibiting nuclear factor-kappa B (NF-κB) signaling pathway (the reduced levels of toll-like receptor 4 [TLR4], myeloid differentiation factor 88 [MyD88], and NF-κB). Finally, our results showed that LPC regulated gut microbiota by enhancing the percentage of Ligilactobacillus and decreasing Alistipes and Barnesiella. In summary, we found that LP postbiotic was effective to protect broilers against Salmonella infection, possibly through suppressing NLRP3 inflammasome and optimizing gut microbiota. Our study provides the potential of postbiotics on prevention of Salmonella infection in poultry.

Benefits of heat-killed Lactobacillus acidophilus on growth performance, nutrient digestibility, antioxidant status, immunity, and cecal microbiota of rabbits

Introduction

Heat-killed probiotics, as a type of inactivated beneficial microorganisms, possess an extended shelf life and broader adaptability compared to their live counterparts. This study aimed to investigate the impact of heat-killed Lactobacillus acidophilus (L. acidophilus, LA) - a deactivated probiotic on the growth performance, digestibility, antioxidant status, immunity and cecal microbiota of rabbits.

Methods

Two hundred weaned Hyla rabbits were randomly allocated into five equal groups (CON, L200, L400, L600, and L800). Over a 28-day period, the rabbits were fed basal diets supplemented with 0, 200, 400, 600, and 800 mg/kg of heat-killed LA, respectively.

Results

Results revealed a significant reduction in the feed-to-gain ratio (F/G) in the L600 and L800 groups (p < 0.05). Additionally, the L800 group exhibited significantly higher apparent digestibility of crude fiber (CF) and crude protein (CP) (p < 0.05). Regarding digestive enzyme activities, enhanced trypsin and fibrinase activities were observed in the L600 and L800 groups (p < 0.05). Concerning the regulation of the body's antioxidant status, the L800 group demonstrated elevated levels of superoxide dismutase (SOD) and total antioxidant capacity (T-AOC) in both serum and ileal tissue (p < 0.05). In terms of immune capacity modulation, serum tumor necrosis factor-α (TNF-α) levels were significantly lower in the L600 and L800 groups (p < 0.05), while immunoglobulin A (IgA) and immunoglobulin M (IgM) levels were higher (p < 0.05). Additionally, the L800 group exhibited a substantial increase in secretory immunoglobulin A (SIgA) levels in the intestinal mucosa (p < 0.05). In comparison to the CON group, the L800 group exhibited a significant increase in the relative abundance of Phascolarctobacterium and Alistipes in the cecum (p < 0.05). Phascolarctobacterium demonstrated a positive correlation with SIgA (p < 0.05), IgM (p < 0.01), and Glutathione peroxidase (GSH-Px) (p < 0.05), while displaying a negative correlation with TNF-α levels (p < 0.05). Concurrently, Alistipes exhibited positive correlations with IgA (p < 0.05), IgM (p < 0.05), SIgA (p < 0.01), GSH-Px (p < 0.05), SOD (p < 0.05), and T-AOC (p < 0.01), and a negative correlation with TNF-α (p < 0.05).

Discussion

In conclusion, the dietary incorporation of 600 mg/kg and 800 mg/kg of heat-killed LA positively influenced the growth performance, nutrient digestibility, antioxidant status, immune capacity and cecal microbiota of rabbits. This highlights the potential benefits of utilizing heat-killed probiotics in animal nutrition.

Beyond probiotics: Exploring the potential of postbiotics and parabiotics in veterinary medicine

Postbiotics and parabiotics (PP) are emerging fields of study in animal nutrition, preventive veterinary medicine, and animal production. Postbiotics are bioactive compounds produced by beneficial microorganisms during the fermentation of a substrate, while parabiotics are inactivated beneficial microbial cells, either intact or broken. Unlike probiotics, which are live microorganisms, PP are produced from a fermentation process without live cells and show significant advantages in promoting animal health owing to their distinctive stability, safety, and functional diversity. PP have numerous beneficial effects on animal health, such as enhancing growth performance, improving the immune system and microbiota of the gastrointestinal tract, aiding ulcer healing, and preventing pathogenic microorganisms from colonizing in the skin. Moreover, PP have been identified as a potential alternative to traditional antibiotics in veterinary medicine due to their ability to improve animal health without the risk of antimicrobial resistance. This review comprehensively explores the current research and applications of PP in veterinary medicine. We aimed to thoroughly examine the mechanisms of action, benefits, and potential applications of PP in various species, emphasizing their use specifically in livestock and poultry. Additionally, we discuss the various routes of administration to animals, including feed, drinking water, and topical use. This review also presents in-depth information on the methodology behind the preparation of PP, outlining the criteria employed to select appropriate microorganisms, and highlighting the challenges commonly associated with PP utilization in veterinary medicine.

Association Between Escherichia coli Load in the Gut and Body Weight Gain in Broiler Chickens: A Systematic Review and Meta-Analysis

Escherichia coli is one of the first commensal bacteria to colonize the chicken gut, where it predominates at an early stage of broiler chick life. Escherichia coli can potentially cause colibacillosis in chickens, spreading to extraintestinal systemic organs, which results in high economic losses in poultry industry, as well as a potential risk to public health. Many studies conducted to investigate the effectiveness of natural products as alternatives to antibiotics and to enhance the production performance in broiler chickens have assessed E. coli load in the chicken gut, but it is still unknown how the E. coli count is linked to broiler growth performance. A systematic search of published research articles, including key terms of interest such as broiler chickens, growth performance, and E. coli count, was conducted using two main databases (PubMed and the Web of Science). A random effects metaregression model was built to evaluate the association between E. coli count and weight gain in untreated groups of broilers (negative controls) from eligible studies. Of 2108 articles in the initial screening, 60 were included in the final meta-analysis. After data extraction, records from the ileum and cecum at 21, 35, and 42 days of age were considered for the meta-analysis. The meta-analysis showed that the average E. coli count in both the ileum and cecum at 21 days of age was positively associated with the average weight gain in the studied broiler chickens, while no statistically significant associations were found at 35 and 42 days of age. In conclusion, the positive association between E. coli load and body weight gain in young broiler chickens may be attributed to the relative dominance of E. coli in the gut of this age group when the microbial population is less diverse. The dynamic association between the production performance and the load of E. coli that has dubious pathogenic potential suggests the importance of careful assessment of commensal E. coli to develop strategies to enhance production, particularly in young broiler chickens.