Immunomodulating effects of probiotics for microbiota modulation, gut health and disease resistance in pigs

Microbiota composition of an autochthonous Krškopolje pig breed reared in two different organic production systems

It has been shown that different production systems (conventional vs. pasture-raised pigs) and co-rearing of pigs with other livestock influence the gut microbiota composition in pigs. In this study, two independent trials were conducted to investigate the 16S fecal microbiota of the autochthonous Krškopolje pig. In each trial, three study groups were analyzed: (i) pasture-raised pigs cohabiting with small ruminants (group L1, farm 1), (ii) indoor-raised pigs without contact with other farm animals (group L2, farm 2) and fed the same commercial organic feed as the other two groups, and (iii) pasture-raised pigs cohabiting with cattle (group L3, farm 2). The pigs were sampled four times during the grower-finisher period, corresponding to the different seasons. A total of 18 and 22 pigs were included in trials 1 and 2, respectively. Alpha diversity was comparable between the study groups and the pigs of different age categories. The two predominant bacterial phyla in all three groups were Bacteroidota and Firmicutes. Significant differences in microbiota composition were found between pigs of different age categories in both trials (nonparametric MANOVA, p < 0.008). The microbiota composition of pigs from group L1 was significantly different from that of pigs from groups L2 and L3, whereas groups L2 and L3 tended to be more similar in both trials. The present results indicate that the trial and the farm of origin have a significant influence on the pig gut microbiota, and that their influence is more pronounced than that of the housing system.

Chemical-functional characterization of Ascophyllum nodosum and Phymatolithon calcareum and dietary supplementation in post-weaning pigs

Introduction

As the livestock industry grapples with the need for sustainable land, maintaining production systems, and reducing antimicrobial resistance, the application of functional nutrition emerges as a potential solution.

Aim

In line with the One Health principles, this study aims to evaluate functional properties of Ascophyllum nodosum and Phymatolithon calcareum, and assess the effects of their dietary supplementation on piglets' health.

Materials and methods

A chemical-functional characterization was conducted before and after in vitro digestion. Total Polyphenols Content (TPC) and Total Flavonoid Content (TFC) were determined through colorimetric assays, while antioxidant activity was determined using ABTS assay, and the microdilution method was used to evaluate the antimicrobial capacity. For the in vivo trial twenty-four post-weaning pigs (28 ± 2 days, 6.89 ± 0.820 Kg) were enrolled in two homogeneous groups (n = 12/group): control group (CTRL) fed a commercial diet, and treated group (ALGAE) fed commercial diet with the addition of 1.5% of A. nodosum and 0.5% of P. calcareum for 27 days. Weekly, zootechnical performances were assessed monitoring the body weight and the individual feed intake. Fecal samples were collected to evaluate the abundance of total, lactic acid and coliform bacteria through plate counting. Serum were obtained at day 0 and day 27 to assess the antioxidant barrier.

Results and discussion

The chemical characterization discloses that the minerals' level remains below the maximum thresholds defined for their use in piglets nutrition. TPC was 330.42 ± 21.372 mg TAE/g of the sample and 11.45 ± 0.521 mg TAE/g of the sample for A. nodosum and P. calcareum, respectively, and a similar trend was found in the TFC evaluation (213.85 ± 20.557 and 2.71 ± 0.900 mg CE/g of sample, respectively). Our results also highlighted that polyphenols and flavonoid compounds persisted after in vitro digestion as well as the functional properties. The administration of algae in piglets diet, although it slightly affected feed efficiency in the first period of the trial, did not affect the animal growth in terms of weight and average daily gain. Microbiological analysis of feces showed similar values between the two experimental groups over 27 days. A significantly higher serum antioxidant barrier was registered in ALGAE compared to CTRL group at day 27 (363.26 ± 16.241 vs. 230.69 ± 32.078 HClO/mL, p < 0.05).

Conclusion

In conclusion, the supplementation with A. nodosum and P. calcareum could be considered a promising dietary strategy to enhance the oxidative barrier in weaned piglets.

Limosilactobacillus reuteri B1/1 modulated the intestinal immune response in preventing Salmonella Enteritidis PT4 infection in a chicken ileal explant model

In this study, we observed the effect of the newly isolated probiotic strain Limosilactobacillus reuteri B1/1 on the relative gene expression of selected cytokines (interleukin-15, transforming growth factor-β4), tight junction proteins (E-cadherin, occludin), biomarker active intestinal stem cells - LGR5 (leucine-rich repeat containing G protein-coupled receptor), markers of mucosal intestinal immunity (mucin-2, immunoglobulin A), as well as the creation of a new biomarker of inflammation in the intestine - calprotectin on an ex vivo model of chicken ileal explant in the prevention of Salmonella Enteritidis PT4 infection. The ability of L. reuteri B1/1 to effectively modulate the mucosal immune response under pretreatment conditions in S. Enteritidis PT4 infection in a chicken ileal explant model was confirmed. In addition, our obtained results point to the fact that the new chicken ileum explant model could be a suitable model to investigate or test the influence of natural substances such as probiotic bacteria in the interaction with the intestine as well as pathogenic microorganisms. In addition, the results of our study may contribute to a deeper understanding of the action of newly isolated probiotic bacteria at the intestinal level using ex vivo models such as chicken ileum explant, which are able to mimic in vivo conditions sufficiently.

Dietary Protease Supplementation Improved Growth Performance and Nutrients Digestion via Modulating Intestine Barrier, Immunological Response, and Microbiota Composition in Weaned Piglets

Despite mounting evidence for dietary protease benefits, the mechanisms beyond enhanced protein degradation are poorly understood. This study aims to thoroughly investigate the impact of protease addition on the growth performance, intestinal function, and microbial composition of weaned piglets. Ninety 28-day-old weaned pigs were randomly assigned to the following three experimental diets based on their initial body weight for a 28-day experiment: (1) control (CC), a basic diet with composite enzymes without protease; (2) negative control (NC), a diet with no enzymes; and (3) dietary protease (PR), a control diet with protease. The results show that dietary proteases significantly enhanced growth performance and boosted antioxidant capacity, increasing the total antioxidant capacity (T-AOC) levels (p < 0.05) while reducing malonaldehyde levels (p < 0.05). Additionally, protease addition reduced serum levels of inflammatory markers TNF-α, IL-1β, and IL-6 (p < 0.05), suppressed mRNA expression of pro-inflammatory factors in the jejunum (p < 0.01), and inhibited MAPK and NF-κB signaling pathways. Moreover, protease-supplemented diets improved intestinal morphology and barrier integrity, including zonula occludens protein 1(ZO-1), Occludin, and Claudin-1 (p < 0.05). Microbiota compositions were also significantly altered by protease addition with increased abundance of beneficial bacteria (Lachnospiraceae_AC2044_group and Prevotellaceae_UCG-001) (p < 0.05) and reduced harmful Terrisporobacter (p < 0.05). Further correlation analysis revealed a positive link between beneficial bacteria and growth performance and a negative association with inflammatory factors and intestinal permeability. In summary, dietary protease addition enhanced growth performance in weaned piglets, beneficial effects which were associated with improved intestinal barrier integrity, immunological response, and microbiota composition.

Dietary complex probiotic supplementation changed the composition of intestinal short-chain fatty acids and improved the average daily gain of weaned piglets

Probiotics are a group of active microorganisms that form colonies within the body and alter the composition of the flora in a specific area to provide benefits to the host. In this study, a total of 96 Duroc × Landrace × Yorkshire weaned piglets with an initial body weight (BW) of 8.56 ± 0.53 kg were employed in a randomized complete block design for a 28-day experiment. Pigs were randomly divided into two treatment groups: the control group (CON) and the complex probiotic group (CON + 0.2% probiotics), respectively. The study found that through the 28-day experiment, the average daily gain (ADG) of the complex probiotic group was significantly higher than that of the CON (p < 0.05). However, compared with the CON, the feed conversion efficiency significantly decreased on days 0-14 (p < 0.05). The addition of dietary complex probiotic significantly increased the villus height (VH) of duodenum and ileum, acetate, propionate, butyrate, and total short-chain fatty acids (SCFAs) in feces, and decreased fecal methyl mercaptans, acetic acid, and CO2 (p < 0.05). It concluded that feeding weaned piglets 0.2% complex probiotic increased the VH of duodenum and ileum, as well as changed the content of SCFAs in feces. This ultimately led to an increase in ADG.

Lactobacillus reuteri's multifaceted role in mitigating ionizing radiation-induced injury in Drosophila melanogaster

The numerous beneficial probiotic properties of Lactobacillus reuteri (L. reuteri) include decreasing metabolic syndrome, preventing disorders linked to oxidative stress, improving gut flora imbalances, controlling immunological function, and extending life span. Exposure to ionizing radiation is closely associated with several disorders. We examined the protective and salvaging effects of L. reuteri on ionizing radiation-induced injury to the intestinal tract, reproductive system, and nervous system of Drosophila melanogaster. We also examined its effects on lifespan, antioxidant capacity, progeny development, and behavioral aspects to assess the interaction between L. reuteri and ionizing radiation-induced injury. The findings demonstrated that L. reuteri improved the median survival time following irradiation and greatly extended its lifespan. In addition, it raised SOD activity, reduced ROS levels in intestinal epithelial cells, and increased the quantity of intestinal stem cells. Furthermore, L. reuteri enhanced the adult male flies' capacity to move. It also successfully safeguarded the generations' growth and development. L. reuteri dramatically enhanced expression of the AMPKα gene and regulated expression of its pathway-related gene, mTOR, as well as the autophagy-related genes Atg1 and Atg5 in female Drosophila exposed to irradiation. Notably, no prior reports have been made on the possible effects of L. reuteri on injuries caused by irradiation. As a result, our research offers important new information regarding L. reuteri's possible role as a shield against ionizing radiation-induced injury.

Effects of Lactobacillus rhamnosus DSM7133 on Intestinal Porcine Epithelial Cells

Antimicrobial resistance is one of the biggest health challenges nowadays. Probiotics are promising candidates as feed additives contributing to the health of the gastrointestinal tract. The beneficial effect of probiotics is species/strain specific; the potential benefits need to be individually assessed for each probiotic strain or species. We established a co-culture model, in which gastrointestinal infection was modeled using Escherichia coli (E. coli) and Salmonella enterica serovar Typhimurium (S. enterica serovar Typhimurium). Using intestinal porcine epithelial cells (IPEC-J2), the effects of pre-, co-, and post-treatment with Lactobacillus (L.) rhamnosus on the barrier function, intracellular (IC) reactive oxygen species (ROS) production, proinflammatory cytokine (IL-6 and IL-8) response, and adhesion inhibition were tested. E. coli- and S. Typhimurium-induced barrier impairment and increased ROS production could be counteracted using L. rhamnosus (p < 0.01). S. Typhimurium-induced IL-6 production was reduced via pre-treatment (p < 0.05) and post-treatment (p < 0.01); increased IL-8 secretion was decreased via pre-, co-, and post-treatment (p < 0.01) with L. rhamnosus. L. rhamnosus demonstrated significant inhibition of adhesion for both S. Typhimurium (p < 0.001) and E. coli (p < 0.001 in both pre-treatment and post-treatment; p < 0.05 in co-treatment). This study makes a substantial contribution to the understanding of the specific benefits of L. rhamnosus. Our findings can serve as a basis for further in vivo studies carried out in pigs and humans.

Dietary Probiotics Modulate Gut Barrier and Immune-Related Gene Expression and Histomorphology in Broiler Chickens under Non- and Pathogen-Challenged Conditions: A Meta-Analysis

Data published in the literature about the favorable effects of dietary probiotics on gut health in broiler chickens are inconsistent. To obtain a more comprehensive understanding, we conducted a meta-analysis to assess the effects of probiotics on the gut barrier and immune-related gene expression, histomorphology, and growth in chickens that were either challenged or non-challenged with pathogens. From the 54 articles published between 2012 and 2022, subsets of data, separately for non-challenged and challenged conditions, for response variables were created. The mean dietary probiotic concentrations ranged from 4.7 to 6.2 and 4.7 to 7.2 log₁₀ colony-forming unit/kg under non-challenged and challenged conditions, respectively. Probiotics increased the expression of genes for mucins and tight junction proteins in the jejunum and ileum at weeks 3 and 6. The stimulatory effect of probiotics on tight junction protein expression was partly stronger in challenged than in non-challenged birds. Meta-regressions also showed an anti-inflammatory effect of probiotics under challenged conditions by modulating the expression of cytokines. Probiotics improved villus height at certain ages in the small intestine while not influencing growth performance. Dietary metabolizable energy, crude protein, and days post-infection modified the effects of probiotics on the observed variables. Overall, meta-regressions support the beneficial effects of probiotics on gut integrity and structure in chickens.

Defined Pig Microbiota with a Potential Protective Effect against Infection with Salmonella Typhimurium

A balanced microbiota is a main prerequisite for the host's health. The aim of the present work was to develop defined pig microbiota (DPM) with the potential ability to protect piglets against infection with Salmonella Typhimurium, which causes enterocolitis. A total of 284 bacterial strains were isolated from the colon and fecal samples of wild and domestic pigs or piglets using selective and nonselective cultivation media. Isolates belonging to 47 species from 11 different genera were identified by MALDI-TOF mass spectrometry (MALDI-TOF MS). The bacterial strains for the DPM were selected for anti-Salmonella activity, ability to aggregate, adherence to epithelial cells, and to be bile and acid tolerant. The selected combination of 9 strains was identified by sequencing of the 16S rRNA gene as Bacillus sp., Bifidobacterium animalis subsp. lactis, B. porcinum, Clostridium sporogenes, Lactobacillus amylovorus, L. paracasei subsp. tolerans, Limosilactobacillus reuteri subsp. suis, and Limosilactobacillus reuteri (two strains) did not show mutual inhibition, and the mixture was stable under freezing for at least 6 months. Moreover, strains were classified as safe without pathogenic phenotype and resistance to antibiotics. Future experiments with Salmonella-infected piglets are needed to test the protective effect of the developed DPM.

Feed additives of bacterial origin as an immunoprotective or imunostimulating factor

Since January 2006 when using antibiotics as growth promoters in animal feed have been banned scientists are looking for the best resolution to apply alternative substances. Extensive research into the health-promoting properties of probiotics and prebiotics has led to significant interest in the mechanisms of action of the combined administration of these feed additives as a synbiotic. Subsequent research has led to the development of new products. Among the most important health benefits of additives are, inhibiting the growth of pathogenic bacteria in the GI tract, maintenance of homeostasis, treatment of inflammatory bowel diseases, and increase in immunity. Specific immunomodulatory mechanisms of action are not well understood and the effect is not always positive, though there are no reports of adverse effects of these substances found in the literature. For this reason, research is still being conducted on their proper application. However, due to the difficulties of carrying out research on humans, evidence of the beneficial effect of these additives comes mainly from experiments on animals. The objective of the present work was to assess the effect of probiotics, prebiotics, and synbiotics, as well as new additives including postbiotics, proteobiotics, nutribiotics, and pharmabiotics, on specific immunomodulatory mechanisms of action, increase in immunity, the reduction of a broad spectrum of diseases.

Dietary Bacillus licheniformis shapes the foregut microbiota, improving nutrient digestibility and intestinal health in broiler chickens

Bacillus licheniformis is considered a potential alternative to antibiotic growth promoters of animal growth and health. However, the effects of Bacillus licheniformis on the foregut and hindgut microbiota, and their relationships with nutrient digestion and health, in broiler chickens remain unclear. In this study, we aimed to identify the effects of Bacillus licheniformis BCG on intestinal digestion and absorption, tight junctions, inflammation, and the fore- and hind-gut microbiota. We randomly assigned 240 1-day-old male AA broilers into three treatment groups: CT (basal diet), BCG1 (basal diet + 1.0 × 10⁸ CFU/kg B. licheniformis BCG), and BCG2 (basal diet + 1.0 × 10⁹ CFU/kg B. licheniformis BCG). On day 42, the jejunal and ileal chyme and mucosa were subjected to analysis of digestive enzyme activity, nutrient transporters, tight junctions, and signaling molecules associated with inflammation. The ileal and cecal chyme were subjected to microbiota analysis. Compared with the CT group, the B. licheniformis BCG group showed significantly greater jejunal and ileal α-amylase, maltase, and sucrase activity; moreover, the α-amylase activity in the BCG2 group was higher than that in the BCG1 group (P < 0.05). The transcript abundance of FABP-1 and FATP-1 in the BCG2 group was significantly greater than that in the CT and BCG1 groups, and the GLUT-2 and LAT-1 relative mRNA levels were greater in the BCG2 group than the CT group (P < 0.05). Dietary B. licheniformis BCG resulted in significantly higher ileal occludin, and lower IL-8 and TLR-4 mRNA levels than observed in the CT group (P < 0.05). B. licheniformis BCG supplementation significantly decreased bacterial community richness and diversity in the ileum (P < 0.05). Dietary B. licheniformis BCG shaped the ileac microbiota by increasing the prevalence of f_Sphingomonadaceae, Sphingomonas, and Limosilactobacillus, and contributed to nutrient digestion and absorption; moreover, it enhanced the intestinal barrier by increasing the prevalence of f_Lactobacillaceae, Lactobacillus, and Limosilactobacillus. Dietary B. licheniformis BCG decreased microbial community diversity by diminishing Desulfovibrio, Alistipes, Campylobacter, Vibrio, Streptococcus, and Escherichia coli-Shigella levels, and down-regulating inflammatory associated molecule expression. Therefore, dietary B. licheniformis BCG contributed to digestion and absorption of nutrients, enhanced the intestinal physical barrier, and decreased intestinal inflammation in broilers by decreasing microbial diversity and optimizing the microbiota structure.

Probiotic Limosilactobacillus Reuteri (Lactobacillus Reuteri) Extends the Lifespan of Drosophila Melanogaster through Insulin/IGF-1 Signaling

The term probiotic refers to bacteria that provide a beneficial effect to the host. Limosilactobacillus reuteri (Lactobacillus reuteri) is a probiotic isolated from human breast milk. Although L. reuteri has antimicrobial and anti-inflammatory activities occasionally linked to anti-aging effects, there are no reports of the effects of L. reuteri on longevity. This study evaluated the anti-aging effects of L. reuteri on the lifespan and physiology of Drosophila melanogaster. L. reuteri increased the mean lifespan of fruit flies significantly without reducing the reproductive output, food intake, or locomotor activity. Furthermore, the data suggested that the longevity effect of L. reuteri is mediated by the reduction of the insulin/IGF-1 signaling pathway and the action of reuterin, an antimicrobial compound produced by L. reuteri. These results show that L. reuteri can be used as a probiotic that acts as a dietary restriction mimetic with anti-aging effects.

Morchella esculenta mushroom polysaccharide attenuates diabetes and modulates intestinal permeability and gut microbiota in a type 2 diabetic mice model

Type 2 diabetes mellitus (T2DM) is a health issue that causes serious worldwide economic problems. It has previously been reported that natural polysaccharides have been studied with regard to regulating the gut microbiota, which plays an important role in T2DM. Here, we investigate the effects of Morchella esculenta polysaccharide (MEP) on a high-fat diet (HFD) and streptozotocin (STZ)-induced T2DM in BALB/c mice. The administration of MEP effectively regulated hyperglycemia and hyperlipidemia and improved insulin sensitivity. We also determined an improvement in gut microbiota composition by 16sRNA pyrosequencing. Treatment with MEP showed an increase in beneficial bacteria, i.e., Lactobacillus and Firmicutes, while the proportion of the opportunistic bacteria Actinobacteria, Corynebacterium, and Facklamia decreased. Furthermore, the treatment of T2DM mice with MEP resulted in reduced endotoxemia and insulin resistance-related pro-inflammatory cytokines interleukin 1β (IL-1β), tumor necrosis factor-alpha (TNF-α), and interleukin 6 (IL-6). Moreover, MEP treatment improved intestinal permeability by modulating the expression of the colon tight-junction proteins zonula occludens-1 (ZO-1), occludin, claudin-1, and mucin-2 protein (MUC2). Additionally, MEP administration affects the metagenome of microbial communities in T2DM mice by altering the functional metabolic pathways. All these findings suggested that MEP is a beneficial prebiotic associated with ameliorating the gut microbiota and its metabolites in T2DM.

Effect of probiotic bacteria on porcine rotavirus OSU infection of porcine intestinal epithelial IPEC-J2 cells

Rotavirus infections in nursing or post-weaning piglets are known to cause diarrhea, which can lead to commercial losses. Probiotic supplementation is used as a prophylactic or therapeutic approach to dealing with microbial infections in humans and animals. To evaluate the effect of probiotic bacteria on porcine rotavirus infections, non-transformed porcine intestinal epithelial IPEC-J2 cells were used as an in vitro model, and three different procedures were tested. When cells were exposed to seven probiotics at concentrations of 105, 106, or 107 CFU/mL for 16 h and removed before rotavirus challenge, infection reduction rates determined by flow cytometry were as follows: 15% (106) and 18% (105) for Bifidobacterium longum R0175, 15% (107) and 16% (106) for B. animalis lactis A026, and 15% (105) for Lactobacillus plantarum 299V. When cells were exposed to three selected probiotic strains for 1 h at higher concentrations, that is, 108 and 5 × 108 CFU/mL, before infection with rotavirus, no significant reduction was observed. When the probiotic bacteria were incubated with the virus before cell infection, a significant 14% decrease in the infection rate was observed for B. longum R0175. The results obtained using a cell-probiotics-virus platform combined with flow cytometry analysis suggest that probiotic bacteria can have a protective effect on IPEC-J2 cells before infection and can also prevent rotavirus infection of the cells.

The gas production, ruminal fermentation parameters, and microbiota in response to Clostridium butyricum supplementation on in vitro varying with media pH levels

The aim of this study was to investigate the gas production (GP), dry matter disappearance (DMD), fermentation parameters, and rumen microbiota in response to Clostridium butyricum (CB) supplementation in batch culture using a high forage substrate. The doses of CB were supplemented at 0 (Control), 0.5 × 10⁶, 1 × 10⁶, and 2 × 10⁶  CFU/bottle, respectively, at either media pH 6.0 or pH 6.6. The 16S rRNA gene sequencing was used to detect the microbiota of fermentation culture in control and 1 × 10⁶  CFU/bottle after 24 h of incubation. The results showed that the GP (p < 0.001), DMD (p = 0.008), total volatile fatty acid (VFA) concentration (p < 0.001), acetate to propionate ratio (p < 0.001), and NH₃-N concentration (p < 0.001) were greater at media pH 6.6 than pH 6.0. Furthermore, the linearly increased DMD (pH 6.0, p = 0.002; pH 6.6, p < 0.001) and quadratically increased butyrate proportion (pH 6.0, p = 0.076; pH 6.6, p < 0.053) and NH₃-N concentration (pH 6.0, p = 0.003; pH 6.6, p = 0.014) were observed with increasing doses of CB. The Alpha diversity indexes of OTU number and Chao1 were higher (p = 0.045) at media pH 6.6 than pH 6.0, but they were not affected by CB supplementation. The PCoA analysis (unweighted uniFrac) demonstrated that the clustering of the bacterial microbiota of control and CB were distinctly separated from each other at media pH 6.0. At the phylum level, the abundance of Bacteroidota (p < 0.001) decreased, whereas that of Firmicutes (p = 0.026) increased when the media pH was elevated from 6.0 to 6.6. Supplementation of CB increased relative abundances of Rikenellaceae_RC9_gut_group (p = 0.002), Christensenellaceae_R-7_group (p < 0.001), and NK4A214_group (p = 0.002) at genus level. Interactions between media pH and CB addition were observed for bacteria at both phylum and genus levels. These results indicated that increasing the media pH level and CB supplementation increased in vitro rumen digestibility, and altered the ruminal fermentation pattern (by media pH) and microbiota.

In vitro and in vivo evaluation of probiotic potential and safety assessment of Bacillus coagulans SKB LAB-19 (MCC 0554) in humans and animal healthcare

Bacillus coagulans is Gram positive, spore forming and high lactic acid producing bacteria; however, probiotic and safety assessment of the isolated strain need to be investigated for commercial applications. Current study aimed to screen SKB LAB-19 for potential probiotic characteristics viz. enzyme production, antimicrobial properties, pH/bile salt tolerance, temperature stability, antidiarrheal activity in Swiss albino mice and Wistar rats; and acute oral toxicity in mice. The results showed that, SKB LAB-19 produces eight potential enzymes, effective against E. coli and C. perfringensis, tolerant to bile salt (0.3%)/gastric pH (2.5), stable at 40-90 °C and nontoxic to cells. SKB LAB-19 was found to be safe and displayed promising results to reverse E. coli and castor oil induced diarrhoea. Histopathological studies showed repair to damaged mucosal epithelium cells and improves integrity of the goblet cells of colon. SKB LAB-19 showed immunomodulatory effects with increased immunoglobulins in blood and augmented weight of spleen and thymus. In addition, SKB LAB-19 showed significant in-vitro antioxidant activity (82.93%), reducing capacity and ascorbate auto-oxidation inhibition effect (94.62%). These preliminary results suggested that, SKB LAB-19 was found to be safe and has the potential to be used as effective probiotic and anti-diarrhoeal agent in humans and animal healthcare.

Gut microbiome-produced metabolites in pigs: a review on their biological functions and the influence of probiotics

The gastrointestinal tract is a complex ecosystem that contains a large number of microorganisms with different metabolic capacities. Modulation of the gut microbiome can improve the growth and promote health in pigs. Crosstalk between the host, diet, and the gut microbiome can influence the health of the host, potentially through the production of several metabolites with various functions. Short-chain and branched-chain fatty acids, secondary bile acids, polyamines, indoles, and phenolic compounds are metabolites produced by the gut microbiome. The gut microbiome can also produce neurotransmitters (such as γ-aminobutyric acid, catecholamines, and serotonin), their precursors, and vitamins. Several studies in pigs have demonstrated the importance of the gut microbiome and its metabolites in improving growth performance and feed efficiency, alleviating stress, and providing protection from pathogens. The use of probiotics is one of the strategies employed to target the gut microbiome of pigs. Promising results have been published on the use of probiotics in optimizing pig production. This review focuses on the role of gut microbiome-derived metabolites in the performance of pigs and the effects of probiotics on altering the levels of these metabolites.

The sow microbiome: Current and future perspectives to maximize the productivity in swine herds

The development of new generation sequencing methods and the reduction in the cost per base sequenced over the past few years is drawing the attention of the pig industry to microbiome understanding and modulation. In recent years, there has been an increase in the number of articles published related to microbiome studies in swine. With respect to sows, microbiome studies mainly focused on the gut, with some studies evaluating the reproductive tract and mammary microbiome. However, studies about urinary microbiome are still lacking. The present literature indicates that the microbiome in the sow’s gut can affect the microbiome in other body parts. Moreover, the understanding of the dynamics and interactions among microbial populations within the sow or the herd has led to improvements in animal health and reproductive performance. This review provides new insights related to sow intestinal, urinary, mammary, and reproductive microbiomes and their relationships with reproductive outcomes, diseases, and early colonization in offspring by gathering the most recent work in this field as well as pinpoints information gaps that require further investigation. This literature review also sheds light on the knowledge regarding the role of microbiomes in the reduction of antimicrobial use.

Effects of Bacillus licheniformis and Bacillus subtilis on Gut Barrier Function, Proinflammatory Response, ROS Production and Pathogen Inhibition Properties in IPEC-J2—Escherichia coli/Salmonella Typhimurium Co-Culture

The emergence of antimicrobial resistance raises serious concerns worldwide. Probiotics offer a promising alternative to enhance growth promotion in farm animals; however, their mode of action still needs to be elucidated. The IPEC-J2 cell line (porcine intestinal epithelial cells) is an appropriate tool to study the effect of probiotics on intestinal epithelial cells. In our experiments, IPEC-J2 cells were challenged by two gastrointestinal (GI) infection causing agents, Escherichia coli (E. coli) or Salmonella enterica ser. Typhimurium (S. Typhimurium). We focused on determining the effect of pre-, co-, and post-treatment with two probiotic candidates, Bacillus licheniformis or Bacillus subtilis, on the barrier function, proinflammatory cytokine (IL-6 and IL-8) response, and intracellular reactive oxygen species (ROS) production of IPEC-J2 cells, in addition to the adhesion inhibition effect. Bacillus licheniformis (B. licheniformis) and Bacillus subtilis (B. subtilis) proved to be anti-inflammatory and had an antioxidant effect under certain treatment combinations, and further effectively inhibited the adhesion of pathogenic bacteria. Interestingly, they had little effect on paracellular permeability. Based on our results, Bacillus licheniformis and Bacillus subtilis are both promising candidates to contribute to the beneficial effects of probiotic multispecies mixtures.

Effect of Enterococcus faecium NCIMB 10415 on Gut Barrier Function, Internal Redox State, Proinflammatory Response and Pathogen Inhibition Properties in Porcine Intestinal Epithelial Cells

In farm animals, intestinal diseases caused by Salmonella spp. and Escherichia coli may lead to significant economic loss. In the past few decades, the swine industry has largely relied on the prophylactic use of antibiotics to control gastrointestinal diseases. The development of antibiotic resistance has become an important issue both in animal and human health. The use of antibiotics for prophylactic purposes has been banned, moreover the new EU regulations further restrict the application of antibiotics in veterinary use. The swine industry seeks alternatives that are capable of maintaining the health of the gastrointestinal tract. Probiotics offer a promising alternative; however, their mode of action is not fully understood. In our experiments, porcine intestinal epithelial cells (IPEC-J2 cells) were challenged by Salmonella Typhimurium or Escherichia coli and we aimed at determining the effect of pre-, co-, and post-treatment with Enterococcus faecium NCIMB 10415 on the internal redox state, paracellular permeability, IL-6 and IL-8 secretion of IPEC-J2 cells. Moreover, the adhesion inhibition effect was also investigated. Enterococcus faecium was able to reduce oxidative stress and paracellular permeability of IPEC-J2 cells and could inhibit the adhesion of Salmonella Typhimurium and Escherichia coli. Based on our results, Enterococcus faecium is a promising candidate to maintain the health of the gastrointestinal tract.

Bacillus spp. Probiotic Strains as a Potential Tool for Limiting the Use of Antibiotics, and Improving the Growth and Health of Pigs and Chickens

The pressure to increasingly optimize the breeding of livestock monogastric animals resulted in antimicrobials often being misused in an attempt to improve growth performance and counteract diseases in these animals, leading to an increase in the problem of antibiotic resistance. To tackle this problem, the use of probiotics, also known as direct in-feed microbials (DFM), seems to be one of the most promising strategies. Among probiotics, the interest in Bacillus strains has been intensively increased in recent decades in pigs and poultry. The aim of the present review was to evaluate the effectiveness of Bacillus strains as probiotics and as a potential strategy for reducing the misuse of antibiotics in monogastric animals. Thus, the potential modes of action, and the effects on the performance and health of pigs (weaning pigs, lactation and gestation sows) and broilers are discussed. These searches yielded 131 articles (published before January 2021). The present review showed that Bacillus strains could favor growth in terms of the average daily gain (ADG) of post-weaning piglets and broilers, and reduce the incidence of post-weaning diarrhea in pigs by 30% and mortality in broilers by 6-8%. The benefits of Bacillus strains on these parameters showed results comparable to the benefit obtained by the use of antibiotics. Furthermore, the use of Bacillus strains gives promising results in enhancing the local adaptative immune response and in reducing the oxidative stress of broilers. Fewer data were available regarding the effect on sows. Discordant effects have been reported regarding the effect on body weight (BW) and feed intake while a number of studies have supported the hypothesis that feeding probiotics to sows could benefit their reproductive performance, namely the BW and ADG of the litters. Taken all the above-mentioned facts together, this review confirmed the effectiveness of Bacillus strains as probiotics in young pigs and broilers, favoring their health and contributing to a reduction in the misuse of direct in-feed antibiotics. The continuous development and research regarding probiotics will support a decrease in the misuse of antibiotics in livestock production in order to endorse a more sustainable rearing system in the near future.

Intestinal microbiota and its interaction to intestinal health in nursery pigs

The intestinal microbiota has gained increased attention from researchers within the swine industry due to its role in promoting intestinal maturation, immune system modulation, and consequently the enhancement of the health and growth performance of the host. This review aimed to provide updated scientific information on the interaction among intestinal microbiota, dietary components, and intestinal health of pigs. The small intestine is a key site to evaluate the interaction of the microbiota, diet, and host because it is the main site for digestion and absorption of nutrients and plays an important role within the immune system. The diet and its associated components such as feed additives are the main factors affecting the microbial composition and is central in stimulating a beneficial population of microbiota. The microbiota–host interaction modulates the immune system, and, concurrently, the immune system helps to modulate the microbiota composition. The direct interaction between the microbiota and the host is an indication that the mucosa-associated microbiota can be more effective in evaluating its effect on health parameters. It was demonstrated that the mucosa-associated microbiota should be evaluated when analyzing the interaction among diets, microbiota, and health. In addition, supplementation of feed additives aimed to promote the intestinal health of pigs should consider their roles in the modulation of mucosa-associated microbiota as biomarkers to predict the response of growth performance to dietary interventions.

Effect of fiber and energy in diet on productivity and formation of microbiocenosis in piglets

Today, an important role in the development of pig breeding is given to feeding animals, especially piglets during the transition from milk to vegetable feeding. This crucial period is associated with physiological characteristics of piglet growth and development. Therefore, the problem of developing mixed fodder that gives rise to high weight gain in piglets is relevant for pig farming. The experiments were conducted on piglets aged 15-42 days in Nadezhda farm, Kursk region. The purpose of the research was to increase productivity and form the microbiocenosis in the intestines of piglets. During the study period, barley-wheat mixed fodder was used with additional ingredients: feed fat, alfalfa grass flour and probiotic. Feed fats provide an optimal level of energy for piglets growth. The active substances of alfalfa flour are involved in all metabolic processes in the body, making it effective. Probiotic increases availability and digestibility of feed nutrients. The studies proved that the new composition of SK-3 increased the average daily weight gain by 20.5 %, the gross formation per piglet increased to 21 %. At the same time, survival of animals in the period 15-42 days increased to 100 %. The greatest growth of beneficial intestinal microflora from 107 to 109 CFU/g of feces was observed after feeding experimental piglets with mixed fodder containing grass flour, feed fats and probiotic by day 42. In comparison with the control animals, experimental animals showed a decrease in E. coli - from 107 to 104. The importance of using such ingredients as alfalfa grass flour, feed fats and probiotic in mixed fodder for piglets of 15-42 days of age was revealed. The relevance of the development of new mixed fodder was justified.

Genomic Analysis of Limosilactobacillus fermentum ATCC 23271, a Potential Probiotic Strain with Anti-Candida Activity

Limosilactobacillus fermentum (ATCC 23271) was originally isolated from the human intestine and has displayed antimicrobial activity, primarily against Candida species. Complete genome sequencing and comparative analyses were performed to elucidate the genetic basis underlying its probiotic potential. The ATCC 23271 genome was found to contain 2,193,335 bp, with 2123 protein-coding sequences. Phylogenetic analysis revealed that the ATCC 23271 strain shares 941 gene clusters with six other probiotic strains of L. fermentum. Putative genes known to confer probiotic properties have been identified in the genome, including genes related to adhesion, tolerance to acidic pH and bile salts, tolerance to oxidative stress, and metabolism and transport of sugars and other compounds. A search for bacteriocin genes revealed a sequence 48% similar to that of enterolysin A, a protein from Enterococcus faecalis. However, in vitro assays confirmed that the strain has inhibitory activity on the growth of Candida species and also interferes with their adhesion to HeLa cells. In silico analyses demonstrated a high probability of the protein with antimicrobial activity. Our data reveal the genome features of L. fermentum ATCC 23271, which may provide insight into its future use given the functional benefits, especially against Candida infections.

Screening of probiotic candidates in a simulated piglet small intestine in vitro model

The CoMiniGut in vitro model mimicking the small intestine of piglets was used to evaluate four probiotic strains for their potential as a preventive measure against development of diarrhea in weaned pigs. In the in vitro system, piglet digesta was inoculated with pathogenic enterotoxigenic Escherichia coli F4 (ETEC F4), and the short-chain fatty acid profile and the gut microbiota composition were assessed. A total of four probiotic strains were evaluated: Enterococcus faecium (CHCC 10669), Lactobacillus rhamnosus (CHCC 11994), Bifidobacterium breve (CHCC 15268) and Faecalibacterium prausnitzii (CHCC 28556). The significant differences observed in metabolite concetration and bacterial enumeration were attributed to variation in inoculating material or pathogen challenge rather than probiotic treatment. Probiotic administration influenced the microbiota composition to a small extend. Learnings from the present study indicate that the experimental setup, including incubation time and choice of inoculating material, should be chosen with care.

Age Matters: Community Assembly in the Pig Fecal Microbiome in the First Month of Life

Despite the wealth of research into strategies for microbiome modulation, studies of microbiome management in pig hosts have found mixed results. A refined understanding of the patterns of microbiome assembly during the host’s early life, when management strategies are most commonly applied, is necessary for the development of successful management practices. Here, we study the development of the pig gut microbial community in a monitoring experiment, sampling the microbiome of pigs in a commercial farm intensively during the first month of life. We found that the community’s taxonomic richness increased linearly with host age. Furthermore, rapid changes across communities occurred in stages, and non-linear patterns in relative abundance were commonly observed among dominant taxa across host age, consistent with primary succession. Our results highlight the importance of understanding the patterns of microbiome assembly during host development, and identify successional stages as windows of opportunity for future research.

Characterization and comparison of the bacterial community between complete intensive and extensive feeding patterns in pigs

To investigate and compare the gut microbiota structures in complete intensive feeding pattern (CP) and extensive feeding pattern (EP) groups, a total of 20 pigs were divided into two groups and fed the same diet. The fecal microbial composition was profiled using 16S rRNA gene sequencing. Our results showed that seventeen predominant genera were present in each pig sample and constituted the phylogenetic core of the microbiota at the class level. The abundance of most of the core microbial flora were significantly higher in the CP group than in the EP group (P < 0.05), while the abundance of Gammaproteobacteria was significantly lower in the CP group than in the EP group (P < 0.05). The CP group had significantly greater community diversity, richness, and evenness than the EP group (P < 0.05). Functional prediction analysis indicated that intestinal microbial species potentially led to faster growth and an increased fat accumulation capacity in the CP group; however, disease resistance was weaker in the CP group than in the EP group. In conclusion, EP pigs have a wider range of activity and better animal welfare than CP pigs, which helps reduce the occurrence of diseases and neurological symptoms. To explore the effect of intestinal flora on disease resistance in pigs at the molecular level, Coprococcus, which is a key gut bacterium in the intestine, was selected for isolation and purification and cocultured with intestinal epithelial cells. qPCR was performed to determine the effect of Coprococcus on SLA-DRB gene expression in intestinal epithelial cells. The results showed that Coprococcus enhanced SLA-DRB gene expression in intestinal epithelial cells. The results provide useful reference data for further study on the relationship between intestinal flora and pig disease resistance.

Timely Control of Gastrointestinal Eubiosis: A Strategic Pillar of Pig Health

The pig gastrointestinal tract (GIT) is an open ecosystem in which microorganisms and their host are mutually involved and continually adapt to different factors and problems which may or may not be host dependent or due to the production system. The aim of the present review is to highlight the factors affecting the GIT microbial balance in young pigs, focusing on the pre- and post-weaning phases, to define a road map for improving pig health and the production efficiency of the food chain. Birth and weaning body weight, physiological maturation, colostrum and milk (composition and intake), genetic background, environmental stressors and management practices, antibiotic use and diet composition are considered. Overall, there is a lack of knowledge regarding the effect that some factors, including weaning age, the use of creep feed, the composition of the colostrum and milk and the use of antibiotics, may have on the gut microbiome of piglets. Furthermore, the information on the gut microbiome of piglets is mainly based on the taxonomy description, while there is a lack of knowledge regarding the functional modification of the microbiota, essential for the exploitation of microbiota potential for modulating pig physiology.

Herd-Level and Individual Differences in Fecal Lactobacilli Dynamics of Growing Pigs

Simple Summary

Selection for hyper-prolific sows has led to increased litter size, decreased birth weight, and increased within-litter variation. This is accompanied by impaired colostrum intake of piglets and poor performance. We aimed to investigate the total count of fecal lactobacilli and species diversity in growing pigs on two herds. Study pigs were categorized either small or large according to their birth weight. Sow colostrum quality and colostrum supply of piglets were determined. We hypothesized that the birth weight and growth performance of pigs are associated with fecal lactobacilli composition, which is influenced by colostrum. Small pigs had higher lactobacilli counts in both herds, but the difference was significant only for one herd (p = 0.01). Colostrum quality was numerically better in the herd that appeared also better managed in comparison to the other study herd. Colostrum intake tended to be significantly associated with the total lactobacilli count in the better-managed herd. In conclusion, herd-level factors clearly contribute to the microbiota of pigs, but birth weight also plays a potential role in the gastrointestinal tract lactobacilli dynamics. Our results revealed a potential long-term effect of colostrum, and therefore give a reason to investigate more thoroughly the associations between maternal immunity, pig microbiota, and performance.

Abstract

We studied the fecal lactobacilli count and species diversity of growing pigs along with immune parameters associated with intestinal lactobacilli. Thirty pigs categorized as small (S, n = 12) or large (L, n = 18) at birth were followed from birth to slaughter in two commercial herds, H1 and H2. Herds differed in terms of their general management. We determined sow colostrum quality, colostrum intake, piglet serum immunoglobulins, and pig growth. We took individual fecal samples from pigs in the weaning and finishing units. We studied lactobacilli count and identified their diversity with 16S PCR. Total lactobacilli count increased in H1 and decreased in H2 between samplings. Lactobacilli species diversity was higher in H1 in both fecal sampling points, whereas diversity decreased over time in both herds. We identified altogether seven lactobacilli species with a maximum of five (one to five) species in one herd. However, a relatively large proportion of lactobacilli remained unidentified with the used sequencing technique. Small pigs had higher lactobacilli counts in both herds but the difference was significant only in H2 (p = 0.01). Colostrum quality was numerically better in H1 than in H2, where colostrum intake tended to be associated with total lactobacilli count (p = 0.05).

Concept and principles of development of a new generation symbiotic preparation

The article presents the results of the research on the cultivation of B. bifidum and B. subtillis in a high-carbohydrate nutrient medium composed of beet molasses, obtaining metabolites and scientific and practical substantiation of the resulting culture liquid as a biologically active additive. The material of the laboratory studies was sugar beet molasses of 5%-10%-15%-20%-25% concentrations. The studies used the probiotic microorganism B. bifidum, strain No. 1 and B. subtilis, strain DSM-3242. To obtain bacterial concentrate, a daily culture of microorganisms was used, which was standardized to 1×106 CFU / cm3. The testing process was carried out according to the indicators of the mass fraction of fermented sugars, determined by the calculation method, branch standard OCT 18-395-82. The number of CFU was calculated in the Goryaev chamber using the method of GPhA (General Pharmacopeic Article) 1.7.2.0008.15. The content of amino acids, vitamins, and organic acids in the culture fluid was determined by capillary electrophoresis in the device “Drops”. During the cultivation of B. bifidum and B. subtillis, a certain metabolic activity of their vitality was found, which is expressed in a decrease in the mass fraction of the amount of fermented sugars in the range of 53.7% to 23.7%. The hydrogen index is from 6.70 to 3.77 in experimental samples of molasses. The number of B. bifidum and B. subtillis CFUs cultivated on 5% molasses on the second day reached 7x106 CFU/cm3 and 8.2 × 106 cm3. In other concentrations, a maximum indicator of the number of microorganisms occurred on the third day and did not exceed 6.6 and 7 × 106 CFU/cm3. A significant synthesis of metabolites in the form of indispensable and conditionally dispensable amino acids and organic acids was determined. The dynamics of amino acid synthesis is consistent with the amylolytic and enzymatic activity of microorganisms in the molasses culture medium. In this case the level of enzymes is directly dependent on the number of CFU.

Modern concept of probiotics and principles of development of new-generation symbiotic preparations

The purpose of this work is to review data on the biological effectiveness of probiotics, their mechanisms of action, and the prospects for the development of new-generation preparations. Scientific and practical justification of symbiotic drugs of a new generation – metabiotics as a continuation of the probiotic concept is given. The authors discuss the literature data and their own results, which allow them to propose new approaches to the creation of symbiotic drugs. The authors scientifically substantiate the main scientific provisions of the probiotic concept for the development of new-generation symbiotic drugs:

The Effect of Bacillus licheniformis-Fermented Products and Postpartum Dysgalactia Syndrome on Litter Performance Traits, Milk Composition, and Fecal Microbiota in Sows

This study was designed to evaluate the effects of Bacillus licheniformis-fermented products (BLFP) and postpartum dysgalactia syndrome (PDS) on litter performance traits, milk composition, and fecal microbiota in sows in a commercial farrow to finish pig farm. Fifty multiparous cross-bred pregnant sows were randomly assigned to two groups in a completely randomized design. The dietary treatments comprised a basal diet (pregnancy and nursery diet) as control and basal diet supplemented with 1.5 g/kg of BLFP. Sows with PDS in the two groups were further verified 12 h post-partum. Results show that the piglet body weight at weaning was increased in sows fed the BLFP compared to those fed the control diet. The milk fat content of prepartum sows was reduced in sows fed the BLFP. Postpartum sows with PDS had increased milk solid content compared with healthy sows. Microbial composition and species relative abundance analysis indicated distinct bacterial clusters between the groups. The abundance of the family Prevotellaceae in the feces decreased in sows with PDS. BLFP increased the average abundance of the genus (Eubacterium) coprostanoligenes group in feces of sows. These findings demonstrate that BLFP in the diet of sows can improve the piglet body weight at weaning and modulate the fecal microbiota of sows. PDS also has an impact on milk composition and fecal microbiota in sows.

Lactic Acid Bacteria: Food Safety and Human Health Applications

Research on lactic acid bacteria has confirmed how specific strains possess probiotic properties and impart unique sensory characteristics to food products. The use of probiotic lactic acid bacteria (LAB) in many food products, thus confers various health benefits to humans when they are frequently consumed in adequate amounts. The advent of functional food or the concept of nutraceuticals objectively places more emphasis on seeking alternatives to limit the use of medications thus promoting the regular consumption of fermented foods. Probiotic use has thus been recommended to fulfill the role of nutraceuticals, as no side effects on human health have been reported. Probiotics and lactic acid bacteria can boost and strengthen the human immune system, thereby increasing its resistance against numerous disease conditions. Consumer safety and confidence in dairy and fermented food products and the desire of the food industry to meet the sensory and health needs of consumers, has thus increased the demand for probiotic starter cultures with exceptional performance coupled with health benefiting properties. The potential of probiotic cultures and lactic acid bacteria in many industrial applications including fermented food products generally affects product characteristics and also serves as health-promoting foods for humans. The alleviation of lactose intolerance in many populations globally has been one of the widely accepted health claims attributed to probiotics and lactic acid bacteria, although many diseases have been treated with probiotic lactic acid bacteria and have been proven with scientific and clinical studies. The aim of our review was to present information related to lactic acid bacteria, the new classification and perspectives on industrial applications with a special emphasis on food safety and human health.

Mechanistic insight into the gut microbiome and its interaction with host immunity and inflammation

The intestinal tract is a host to 100 trillion of microbes that have co-evolved with mammals over the millennia. These commensal organisms are critical to the host survival. The roles that symbiotic microorganisms play in the digestion, absorption, and metabolism of nutrients have been clearly demonstrated. Additionally, commensals are indispensable in regulating host immunity. This is evidenced by the poorly developed gut immune system of germ-free mice, which can be corrected by transplantation of specific commensal bacteria. Recent advances in our understanding of the mechanism of host–microbial interaction have provided the basis for this interaction. This paper reviews some of these key studies, with a specific focus on the effect of the microbiome on the immune organ development, nonspecific immunity, specific immunity, and inflammation.

Replacing dietary antibiotics with 0.20% l-glutamine and synbiotics following weaning and transport in pigs

Dietary antibiotic use has been limited in swine production due to concerns regarding antibiotic resistance. However, this may negatively impact the health, productivity, and welfare of pigs. Therefore, the study objective was to determine if combining dietary synbiotics and 0.20% l-glutamine would improve pig growth performance and intestinal health following weaning and transport when compared with traditionally used dietary antibiotics. Because previous research indicates that l-glutamine improves swine growth performance and synbiotics reduce enterogenic bacteria, it was hypothesized that supplementing diets with 0.20% l-glutamine (GLN) and synbiotics (SYN; 3 strains of Lactobacillus [1.2 × 10^9 cfu/g of strain/pig/d] + β-glucan [0.01 g/pig/d] + fructooligosaccharide [0.01 g/pig/d]) would have an additive effect and improve pig performance and intestinal health over that of dietary antibiotics. Mixed-sex pigs (N = 226; 5.86 ± 0.11 kg body weight [BW]) were weaned (19.4 ± 0.2 d of age) and transported for 12 h in central Indiana. Pigs were blocked by BW and allotted to one of two dietary treatments (5 to 6 pigs per pen): antibiotics (positive control [PC]; chlortetracycline [441 ppm] + tiamulin [38.5 ppm]), no antibiotics (negative control [NC]), GLN, SYN, or the NC diet with both the GLN and SYN additives (GLN + SYN) fed for 14 d. From day 14 post-weaning to the end of the grow-finish period, all pigs were provided common antibiotic-free diets. Data were analyzed using PROC GLIMMIX and PROC MIXED in SAS 9.4. Overall, haptoglobin was greater (P = 0.03; 216%) in NC pigs compared with PC pigs. On day 13, GLN and PC pigs tended to have reduced (P = 0.07; 75.2% and 67.3%, respectively) haptoglobin compared with NC pigs. On day 34, the jejunal goblet cell count per villi and per millimeter tended to be greater (P < 0.08; 71.4% and 62.9%, respectively) in SYN pigs compared with all other dietary treatments. Overall, jejunal mucosa tumor necrosis factor-alpha (TNFα) gene expression tended to be greater (P = 0.09; 40.0%) in NC pigs compared with PC pigs on day 34. On day 34, jejunal mucosa TNFα gene expression tended to be greater (P = 0.09; 33.3%, 41.2%, and 60.0%, respectively) in GLN pigs compared with SYN, GLN + SYN, and PC pigs. Although it was determined that some metrics of pig health were improved by the addition of GLN and SYN (i.e., haptoglobin and goblet cell count), overall, there were very few differences detected between dietary treatments and this may be related to the stress load incurred by the pigs.

In Vitro Characterization of Indigenous Probiotic Strains Isolated from Colombian Creole Pigs

Three lactic acid strains were isolated from feces of the native Zungo Pelado breed of pigs (n = 5) and presumably identified as belonging to the Lactobacillaceae family by morphological techniques showing that they were Gram-positive/rod-shaped and catalase- and oxidase-negative. They were then identified by biochemical tests using API 50CHL as Lactobacillus plantarum (CAM6), Lactobacillus brevis (CAM7), and Lactobacillus acidophilus (CL4). However, 16S rRNA identification showed that all three strains were Lactobacillus plantarum. Additionally, all three isolates were able to grow in pH 3 and 4. Interestingly, the growth of the CAM7 strain decreased at pH 5.6 compared to that of the CAM6 strain (p < 0.05), and the growth of the CL4 strain was reduced at pH 7(p < 0.05). All three candidates showed good growth on bile salts (≥0.15%), and CAM6 and CAM7 showed better tolerance at higher concentrations (0.30%). Similarly, all strains tolerated sodium chloride (NaCl) concentrations from 2 to 10%. These strains also grew well at all temperatures tested (30, 37, and 42 °C). The CAM6 strain showed in vitro antibacterial activity against selected enteropathogenic bacteria (Escherichia coli strain NBRC 102203 and Salmonella enterica serovar Typhimurium 4.5.12) and commensal bacteria (Klebsiella pneumoniae ATCC BAA-1705D-5 and Pseudomonas aeruginosa ATCC 15442) and resistance to all antibiotics except amoxicillin. Further studies to evaluate the effects of these probiotic candidate strains in commercial pigs are currently underway.

A Review of the Effect of Formic Acid and Its Salts on the Gastrointestinal Microbiota and Performance of Pigs

Out of the alternatives to antibiotics and zinc oxide, organic acids, or simply acidifiers, play significant roles, especially in ensuring gut health and the growth performance of pigs. Regarding acidifiers, formic acid and its salts have shown very promising results in weaning, growing and finishing pigs. Although it is known that the main mechanisms by which acidifiers can improve livestock performance and health are related to the regulation of gastrointestinal pH, an improvement in intestinal digestibility and mineral utilization, and their antimicrobial properties against specific pathogens has been observed, while poor consensus remains in relation to the effect of acidifers on bacteria and the complex microbiome. Therefore, the aim of the present review was to critically evaluate the effects of formic acid and its salts on the performance and the gastrointestinal microbiota balance of pigs.

Interactions between host and gut microbiota in domestic pigs: a review

It is well established that pig gut microbiota plays a critical role in maintaining metabolic homeostasis as well as in a myriad of physiological, neurological and immunological functions; including protection from pathogens and digestion of food materials - some of which would be otherwise indigestible by the pig. A rich and diverse gut microbial ecosystem (balanced microbiota) is the hallmark of good health; while qualitative and quantitative perturbations in the microbial composition can lead to development of various diseases. Alternatively, diseases caused by stressors or other factors have been shown to negatively impact the microbiota. This review focuses primarily on how commensal microorganisms in the gastrointestinal tract of pigs influence biochemical, physiological, immunological, and metabolic processes within the host animal.

The pig as a model for immunology research

The pig is an omnivorous, monogastric species with many advantages to serve as an animal model for human diseases. There are very high similarities to humans in anatomy and functions of the immune system, e g., the presence of tonsils, which are absent in rodents. The porcine immune system resembles man for more than 80% of analyzed parameters in contrast to the mouse with only about 10%. The pig can easily be bred, and there are less emotional problems to use them as experimental animals than dogs or monkeys. Indwelling cannulas in a vein or lymphatic vessel enable repetitive stress-free sampling. Meanwhile, there are many markers available to characterize immune cells. Lymphoid organs, their function, and their role in lymphocyte kinetics (proliferation and migration) are reviewed. For long-term experiments, minipigs (e.g., Göttingen minipig) are available. Pigs can be kept under gnotobiotic (germfree) conditions for some time after birth to study the effects of microbiota. The effects of probiotics can be tested on the gut immune system. The lung has been used for extracorporeal preservation and immune engineering. After genetic modifications are established, the pig is the best animal model for future xenotransplantation to reduce the problem of organ shortage for organ transplantation. Autotransplantation of particles of lymphnodes regenerates in the subcutaneous tissue. This is a model to treat secondary lymphedema patients. There are pigs with cystic fibrosis and severe combined immune deficiency available.

Variation in the pH of experimental diets affects the performance of Lymantria dispar asiatica larvae and its gut microbiota

To study dietary pH effects on Lymantria dispar asiatica larvae and provide a theoretical basis for its control in different forests, phosphate buffers (PBs) of pH 6, 7, and 8 were used to prepare experimental diets. The diet prepared with pH 6 PB was named as DPB6, with pH 8 PB as DPB8, and with pH 7 PB as DPB7 (control). The dietary pH was 5.00 in DPB6, 6.05 in control, and 6.50 in DPB8. After feeding on the diets with different pH values for 84 hr, fourth-instar caterpillars were randomly collected. Growth and various physiological traits were determined and 16S recombinant DNA sequencing was performed using the intestinal microflora of surviving larvae. Results showed that the mortality was 30% in DPB6, and 10% in DPB8, while no mortality was observed in control. The partial least squares discriminant analyses suggested that diets prepared with PB of different pH resulted in different food intake, amount of produced feces, weight gain, digestive enzyme activities, and antioxidant enzyme activities in larvae. Interestingly, both the highest weight gain and the lowest total antioxidant capacities were seen in control larvae. Results also showed that the larval gut microbiota community structure was significantly affected by dietary pH. Moreover, linear discriminant analysis effect size suggested that the family Acetobacteraceae in control, genus Prevotella in DPB8, and genus Lactococcus, family Flavobacteriaceae, family Mitochondria, and family Burkholderiaceae in DPB6 contributed to the diversity of the larval gut microbial community.

Effects of alternative feed additives to medicinal zinc oxide on productivity, diarrhoea incidence and gut development in weaned piglets

The use of medicinal zinc oxide (ZnO) must be phased out by 2022, thus prompting an urgent need for alternative strategies to prevent diarrhoea in weaner piglets. The objectives of this study were to assess the impact on weaner piglet performance, diarrhoea incidence and gut development, when (1) dietary ZnO supplementation was substituted by alternative commercial products based on macroalgae, specific probiotics or synbiotics, or (2) dietary ZnO inclusion was reduced from 2500 to 1500 ppm. A total of 4680 DLY piglets (DanBred, Herlev, Denmark), weaned around 35 days of age, were randomly assigned according to sex and BW to six different dietary treatment groups. A basal diet was supplemented with no ZnO (NC = negative control), 2500 ppm ZnO (PC = positive control), 1500 ppm ZnO (RDZ = reduced dose of ZnO) or commercial macroalgae (OceanFeed™ Swine = OFS), probiotic Miya-Gold or synbiotic GærPlus products. The piglets entered and exited the weaner unit at ~7.0 and 30 kg BW, respectively. In-feed ZnO was provided the first 10 days post-weaning, while the alternative supplements were fed throughout the weaner period. As expected, the average daily feed intake, average daily weight gain (ADG), feed conversion ratio (FCR) and diarrhoea incidence were improved in the PC compared to NC group (P < 0.05) during phase 1 consistent with improved indices of villi development observed in subgroups of piglets sacrificed 11 days post-weaning. Reduction of ZnO to 1500 ppm lowered ADG (P < 0.05) and slightly increased incidence of diarrhoea during the first 10 days after weaning (but not later) without affecting FCR. None of the three alternative dietary additives, including a 10-fold increased dose of GærPlus than recommended, improved piglet performance, gut health and gut development above that of NC piglets. The OFS piglets sacrificed 11 days after weaning had significantly lower weights of hindgut tissue and contents compared to the PC group, consistent with antimicrobial activity of the product, which was detected from anaerobic in vitro fermentation. In conclusion, dietary ZnO supplementation during the first 10 days post-weaning may be reduced from 2500 to 1500 ppm without major negative implications for weaner piglet performance and health in herds under a high management level. However, none of the alternative dietary supplements were able to improve piglet performance or gut health, when ZnO was omitted from the diet.

Probiotics in Animal Husbandry: Applicability and Associated Risk Factors

Probiotics have been emerging as a safe and viable alternative to antibiotics for increasing performance in livestock. Literature was collated via retrieved information from online databases, viz, PubMed, MEDLINE, ScienceDirect, Scopus, Web of Science and Google Scholar. Besides improved immunomodulation and nutrient digestibility, in-feed probiotics have shown drastic reductions in gastrointestinal tract-invading pathogens. However, every novel probiotic strain cannot be assumed to share historical safety with conventional strains. Any strain not belonging to the wild-type distributions of relevant antimicrobials, or found to be harbouring virulence determinants, should not be developed further. Modes of identification and the transmigration potential of the strains across the gastrointestinal barrier must be scrutinized. Other potential risk factors include the possibility of promoting deleterious metabolic effects, excessive immune stimulation and genetic stability of the strains over time. Adverse effects of probiotics could be strain specific, depending on the prevailing immunological and physiological condition of the host. The most crucial concern is the stability of the strain. Probiotics stand a good chance of replacing antibiotics in animal husbandry. The possibility of the probiotics used in animal feed cross-contaminating the human food chain cannot be downplayed. Thus, the established safety measures in probiotic development must be adhered to for a successful global campaign on food safety and security.

Productivity and parameters of blood of sows fed with probiotic supplements

Feeding lactating sows with the probiotic supplements “Citexflor-1” and “Sgol-1-40” at 14.4–13.1 MJ of exchange energy released from digesting 1 kg of dry matter of feed mixtures included in the diet had a positive effect on productivity, nutrient digestibility and morphological and biochemical parameters of blood. The inclusion of adequate amounts of “Citexflor-1” enhanced milk production by sows in the second trial group compared to the control by 2.03 %, in the third by 6.6 % and in the fourth by 3.9 %, with the survival in piglets observed at 89–92 %. Supplementation of probiotic preparation “Sgol-1-40” was carried out, the sows showed to produce more milk by 5.8 % in the second trial group, 16.3 % in the third, and 20.7 % in the fourth group compared to the control. In the study of morphological and biochemical parameters of blood in sows in the first experiment, the erythrocyte number was greater in the third trial group by 6.2 %, and in the fourth by 4.7 %. In the second experiment, with probiotic supplementation of “Sgol-1-40” fed to sows, the number of red blood cells was 4.2; 18.1 and 32.1 % greater, respectively, along with hemoglobin level higher at 2.8; 15.3; 24.1 %, respectively.

Effects of chitosan nanoparticle supplementation on growth performance, humoral immunity, gut microbiota and immune responses after lipopolysaccharide challenge in weaned pigs

In this study, we aimed to determine the effects of dietary supplementation with chitosan nanoparticles (CNP) on growth performance, immune status, gut microbiota and immune responses after lipopolysaccharide challenge in weaned pigs. A total of 144 piglets were assigned to four groups receiving different dietary treatments, including basal diets supplemented with 0, 100, 200 and 400 mg/kg CNP fed for 28 days. Each treatment group included six pens (six piglets per pen). The increase in supplemental CNP concentration improved the average daily gain (ADG) and decreased the feed and gain (F/G) and diarrhoea rate (p < .05). However, significant differences in the average daily feed intake (ADFI) among different CNP concentrations were not observed. CNP also increased plasma immunoglobulin (Ig)A and IgG, and C3 and C4 concentrations in piglets in a dose-dependent manner on day 28, whereas IgM concentration was not affected by CNP. A total of 24 piglets in the control diet and control diet with 400 mg/kg CNP supplementation groups were randomly selected for the experiment of immunological stress. Half of the pigs in each group (n = 6) were injected i.p. with Escherichia coli lipopolysaccharide (LPS) at a concentration of 100 μg/kg. The other pigs in each group were injected with sterile saline solution at the same volume. Plasma concentrations of cortisol, prostaglandin E2 (PEG2), interleukin (IL)-6, tumour necrosis factor (TNF)-α and IL-1β dramatically increased after LPS challenge. However, CNP inhibited the increase in cortisol, PEG2, IL-6 and IL-1β levels in plasma, whereas TNF-α level slightly increased. Moreover, the effects of CNP on the gut microbiota were also evaluated. Our results showed that dietary supplementation with CNP modified the composition of colonic microbiota, where it increased the amounts of some presumably beneficial intestinal bacteria and suppressed the growth of potential bacterial pathogens. These findings suggested CNP supplementation improved the growth performance and immune status, alleviated immunological stress and regulated intestinal ecology in weaned piglets. Based on these beneficial effects, CNP could be applied as a functional feed additives supplemented in piglets diet.

Combined dietary supplementation of long chain inulin and Lactobacillus acidophilus W37 supports oral vaccination efficacy against Salmonella Typhimurium in piglets

Routine use of antibiotics in livestock animals strongly contributed to the creation of multidrug-resistant Salmonella Typhimurium strains (STM). Vaccination is an alternative to the use of antibiotics but often suffers from low efficacy. The present study investigated whether long-chain inulin (lcITF) and Lactobacillus acidophilus W37 (LaW37) can support vaccination efficacy against STM and if the interventions influence possible gut microbiota changes. Piglets received daily supplementation until sacrifice. Animals were vaccinated on day 25 after birth, one day after weaning, and were challenged with STM on days 52–54. Dietary intervention with lcITF/LaW37 enhanced vaccination efficacy by 2-fold during challenge and resulted in higher relative abundance of Prevotellaceae and lower relative abundance of Lactobacillaceae in faeces. Although strongest microbial effects were observed post STM challenge on day 55, transient effects of the lcITF/LaW37 intervention were also detected on day 10 after birth, and post-weaning on day 30 where increased relative abundance of faecal lactobacilli was correlated with higher faecal consistency. LcITF treatment increased post-weaning feed efficiency and faecal consistency but did not support vaccination efficacy. Vaccination in immune-immature young animals can be enhanced with functional additives which can simultaneously promote health in an ingredient-dependent fashion.

Synbiotics impact on dominant faecal microbiota and short-chain fatty acids production in sows

The aim of this study was to estimate the influence of synbiotics on intestinal microbiota and its metabolism in sows. Three different synbiotics were administered with feed to animals from three experimental groups. Two groups of sows were given commercially available probiotics (BioPlus 2B®, Cylactin® LBC) as forage additives for comparison. The control group of sows was given unmodified fodder. The study was conducted for 48 days (10 days before farrowing, and continued 38 days after) and faeces samples were collected four times. The scope of this work was to designate the dominant microbiota in sows' faeces. Therefore, the total number of anaerobic bacteria, Bifidobacterium sp., Lactobacillus sp., Bacteroides sp., Clostridium sp., Enterococcus sp., Enterobacteriaceae, Escherichia coli and yeast was determined, using the plate method. Changes in the concentration of lactic acid, short-chain fatty acids (SCFAs) and branched-chain fatty acids (BCFAs) were also determined in correlation with the feed additives administered to the sows using high-performance liquid chromatography analysis (HPLC). Our results allowed us to conclude that synbiotics have a beneficial effect on intestinal microbiota of sows and its metabolism. We observed that the impact of the synbiotics on the microbiota was more significant than the one induced by probiotics.

Cactus pear (Opuntia ficus-indica) juice fermented with autochthonous Lactobacillus plantarum S-811

The present study aimed at investigating the lactic fermentation of cactus pear (Opuntia ficus-indica) fruit juice with the autochthonous and potentially probiotic strain Lactobacillus plantarum S-811. L. plantarum S-811 was able to quickly acidify the juice with a decrease in the pH from 5.5 to 3.7 and a production of 5.06 g l-1 of lactic acid. Fermentation of cactus pear juice led to conservation of its health-promoting properties and it markedly promoted antioxidant mechanisms in yeast cells, showing in a Saccharomyces cerevisiae model a protective effect of up to 11 times against H2O2 (4 mM), compared to yeasts not supplemented with the fermented juice. Administration of fermented juice to obese mice caused a significant decrease in the body weight gain and ameliorated the insulin resistance, hyperglycemia, and hyperlipemia that characterize obesity. These results reveal the potential of the cactus pear juice fermented with L. plantarum S-811 as a functional beverage for the prevention of obesity and related pathologies.