Background: Probiosis is considered a potential strategy to reduce antibiotics use and prevent post-weaning diarrhea (PWD). This study investigated the effect of Bacillus amyloliquefaciens DSM25840 or Bacillus subtilis DSM25841 supplementation on growth, health, immunity, intestinal functionality and microbial profile of post-weaning pigs after enterotoxigenic E. coli (ETEC) F4 challenge. Methods: Sixty-four post-weaning piglets (7748 g ± 643 g) were randomly allocated to four groups: control basal diet (CO); CO + 1.28 × 10⁶ CFU/g of B. amyloliquefaciens (BAA); CO + 1.28 × 10⁶ CFU/g feed of B. subtilis (BAS); CO + 1 g colistin/kg of feed (AB). At day (d) 7, animals were challenged with 10⁵ CFU/mL of ETEC F4ac O149 and then followed for fecal score and performance until d 21. Blood was collected at d 6, d 12 and d 21 for immunoglobulins, at d 8 for acute phase proteins, at d 8 and d 21 for metabolomics analysis. Jejunum was sampled for morphometry, quantification of apoptosis, cell proliferation, neutral and acid mucine and IgA secretory cells, and microarray analysis at d 21. Jejunum and cecum contents were collected for microbiota at d 21. Results: AB and BAS reduced the fecal score impairment compared to CO (P < 0.05) at d 14. Body weight (BW), average daily weight gain (ADWG), average daily feed intake (ADFI) and gain to feed ratio (G:F) did not differ between Bacillus groups and CO. AB improved BW at d 7, d 14 and d 21, ADWG ADFI and G:F from d 0 to d 7 (P < 0.05). At d 8, CO had higher plasma arginine, lysine, ornithine, glycine, serine and threonine than other groups, and higher haptoglobin than AB (P < 0.05). At d 21, CO had lower blood glycine, glutamine and IgA than BAS. Morphology, cells apoptosis and mucins did not differ. BAS and AB increased the villus mitotic index. Transcriptome profile of BAS and AB were more similar than CO. Gene sets related to adaptive immune response were enriched in BAA, BAS and AB. CO had enriched gene set for nuclear structure and RNA processing. CO had a trend of higher Enterobacteriaceae in cecum than the other groups (P = 0.06). Conclusion: Bacillus subtilis DSM25841 treatment may reduce ETEC F4ac infection in weaned piglets, decreasing diarrhea and influencing mucosal transcriptomic profile.

Ageing is often characterised by nutritional deficiencies and functional alterations of the digestive and immune system. The aim of the present study was to analyse the impact of consumption of conventional milk with A1/A2 beta-casein, compared to milk containing only the A2 beta-casein variant, characterised by a protein profile favouring gut health. Twenty-four ageing Balb-c mice (20 months old) were fed for 4 weeks, with either a control diet (CTRL), a diet supplemented with bovine milk containing A1/A2 beta-casein (A1A2) or a diet containing A2/A2 beta-casein (A2A2). Lymphocyte subpopulations, enzymatic activities, cytokine secretion, gut morphology and histopathological alterations were measured in different gut segments, while short-chain fatty acids (SCFAs) content and microbiota composition were evaluated in faecal samples. The A2A2 group showed higher content of faecal SCFAs (in particular, isobutyrate) of intestinal CD4⁺ and CD19⁺ lymphocytes in the intraepithelial compartment and improved villi tropism. The A1A2 group showed higher percentages of intestinal TCRγδ⁺ lymphocytes. Faecal microbiota identified Deferribacteriaceae and Desulfovibrionaceae as the most discriminant families for the A2A2 group, while Ruminococcaceae were associated to the A1A2 group. Taken together, these results suggest a positive role of milk, in particular when containing exclusively A2 beta-casein, on gut immunology and morphology of an ageing mice model.

Colostrum is the first secretion produced by mammary glands during the hours immediately preceding and succeeding parturition. This secretion differs from milk and represents an essential vehicle of passive immunity, prebiotic compounds and growth factors involved in intestinal development. Most of the literature concerning colostrum composition refers mainly to human and cow; and little is known about pig colostrum metabolome and how it varies between pig breeds and different farrowing parity. Thus, the aim of the present research is to provide new information about pig colostrum composition and the associations between metabolites, the sows’ breed and the survival and growth rates of their litters. Colostrum samples were gathered from 58 parturitions of sows belonging to three different breeds chosen for their importance in Italian heavy pig production: 31 Large White, 15 Landrace and 12 Duroc respectively. The defatted and ultrafiltered colostrum samples were analysed using 1H–NMR spectroscopy. Principal Components Analysis (PCA) was assessed on the obtained spectra. In addition, using a Stepwise Regression and a Linear Regression analyses the metabolites named after the signals assignment were tested for their associations with piglets’ performances. Twenty-five metabolites were identified, comprehending monosaccharides, disaccharides (such as lactose), organic acids (lactate, citrate, acetate and formate), nitrogenous organic acids (such as creatine) and other compounds, including nucleotides. PCA results evidence a clustering due to breed and season effects. Lactose was the main compound determining the assignment of the samples into different clusters according to the sow breed. Furthermore, some metabolites showed to be associated with piglets’ performance and survival traits: acetate and taurine were positively related to litter weight gain and piglets’ survival rate, respectively, while dimethylamine and cis-aconitate were linked to new-borns’ impaired ability to survive. The results obtained suggest that colostrum composition is affected by breed, which, together with environmental conditions, may cause changes in colostrum metabolites content with possible consequences on piglets’ performances. Among the identified metabolites, acetate, taurine, dimethylamine and cis-aconitate showed consistent associations with piglets’ survival rate and litter weight gain, implying that these compounds may affect new-borns’ ability to survive.

The host-microbiota interplay is recognized as a key factor for the homeostatic maintenance in animals. In pigs, the weaning transition represents a drastic changes event leading to high risk of gut dysbiosis, which in most cases results in economic losses for swine industry. The blood type antigens expressed on mucosal surfaces can act as receptors for bacterial adhesion and the hypothesis of possible associations between blood groups and intestinal microbial profiles has been tested in human with contrasting results. Nevertheless, no studies testing the blood type as possible shaping factor for gut microbiota are available for pigs. The results of our previous study suggested the porcine AO blood types system as a possible factor influencing the microbiota composition. In the present study, the changes in fecal microbiota of 12 piglets were followed from 7 days after birth to 2 weeks post-weaning, testing the hypothesis that blood types may impact on its structure. No effects attributable to the difference in blood groups were detected, however, the sampling site (faeces) and the low statistical power might have masked the hypothesized impact. The data clearly showed the rearrangement of the bacterial ecosystem triggered by weaning transition; mainly consisting of a shift from a Bacteroidaceae-Enterobacteriaceae dominated community, to a Prevotellaceae-Ruminococcaceae dominated community. The functional analysis by metagenomic predictions suggested a role of the high levels of long-chain fatty acid in swine milk as energy source for Enterobacteriaceae (E. coli), in suckling piglets. This study provides a first insight for further investigations; indicating the need for larger sample size, preferably derived from intestinal mucosa, to test the potential effect of blood groups on gut microbiota profiles, and for analyses aimed at assessing the long-chain fatty acids degradation activity within the intestinal microbiota of suckling piglets, with particular attention to the role of E. coli.

Putative genetic markers have been associated with ETEC F4 (Mucine 4 [MUC4]; MUC4^GG;CG as susceptible; MUC4^CC as resistant) and F18 (Fucosyltransferase 1 [FUT1]; FUT1^GG;AG as susceptible; FUT1^AA as resistant) resistances respectively. In this study, 71 post‐weaning pigs were followed from d0 (35 days old) to d42 (77 days of age) to investigate the effect of MUC4 or FUT1 genotypes on the mid‐jejunal microbiota composition, pigs expression of genes related to inflammation (IL8, GPX2, REG3G, TFF3, CCL20 and LBPI) and glycomic binding pattern profile (Ulex europaeus agglutinin I [UEA] fucose‐binding lectin and peanut agglutinin [PNA] galactose‐specific), and on blood plasma targeted metabolomics profile, faecal score and performance parameters of growing healthy pigs. The MUC4 and FUT1 resistant genotypes improved the pigs’ growth performance and had firmed faecal score susceptible genotypes in d0–d21 period. Pigs with MUC4^GG genotype had a higher jejunal expression of genes relate to immune function (CCL20 and REG3G) than MUC4^CG and MUC4^CC pigs (p < 0.05). MUC4^CG pigs had higher expression of TFF3 (implicated in mucosal integrity) than MUC4^GG and MUC4^CC (p < 0.05). FUT1 influenced the alpha‐ and beta‐jejunal microbial indices. The FUT1^AA group had a higher number of operational taxonomic units (OTUs) belonging to Lactobacillus genus, while FUT1^GG group had a higher number of OTUs belonging to Veillonella genus. MUC4^CC pigs had lower scores for UEA on brush borders and goblet cells in villi than MUC4^GG (p < 0.05). FUT1^AA pigs had lower UEA positivity and higher PNA positivity on brush borders and goblet cells than FUT1^AG and FUT1^GG (p < 0.05). Both FUT1 and MUC4 influenced the metabolic profile of healthy pigs. Results highlight the role of MUC4 and FUT1 on pig intestinal homoeostasis and improved the knowledge regarding the potential interaction between host genetics, gut microbiota composition and host metabolism in a healthy status.