Tracking the fecal mycobiome through the lifespan of production pigs and a comparison to the feral pig.

IMPORTANCE: This work provides evidence that early-life fungal community composition, or host genetics, influences long-term mycobiome composition. In addition, this work provides the first comparison of the feral pig mycobiome to the mycobiome of intensively raised pigs.

Comparing the impact of mixed-culture microbial communities and fecal transplant on the intestinal microbiota and metabolome of weaned piglets.

Fecal microbiota transplantation (FMT) is an emerging technique for modulating the pig microbiota, however, donor variability is one of the major reasons for inconsistent outcomes across studies. Cultured microbial communities may address some limitations of FMT; however, no study has tested cultured microbial communities as inocula in pigs. This pilot study compared the effects of microbiota transplants derived from sow feces to cultured mixed microbial community (MMC) following weaning. Control, FMT4X, and MMC4X were applied four times, while treatment FMT1X was administered once (n = 12/group). On postnatal day 48, microbial composition was modestly altered in pigs receiving FMT in comparison with Control (Adonis, P = .003), mainly attributed to reduced inter-animal variations in pigs receiving FMT4X (Betadispersion, P = .018). Pigs receiving FMT or MMC had consistently enriched ASVs assigned to genera Dialister and Alloprevotella. Microbial transplantation increased propionate production in the cecum. MMC4X piglets showed a trend of higher acetate and isoleucine compared to Control. A consistent enrichment of metabolites from amino acid metabolism in pigs that received microbial transplantation coincided with enhanced aminoacyl-tRNA biosynthesis pathway. No differences were observed among treatment groups for body weight or cytokine/chemokine profiles. Overall, FMT and MMC exerted similar effects on gut microbiota composition and metabolite production.

Maternal Mycobiome, but Not Antibiotics, Alters Fungal Community Structure in Neonatal Piglets.

Early-life antibiotic exposure is associated with diverse long-term adverse health outcomes. Despite the immunomodulatory effects of gastrointestinal fungi, the impact of antibiotics on the fungal community (mycobiome) has received little attention. The objectives of this study were to determine the impact of commonly prescribed infant antibiotic treatments on the microbial loads and structures of bacterial and fungal communities in the gastrointestinal tract. Thirty-two piglets were divided into four treatment groups: amoxicillin (A), amoxicillin-clavulanic acid (AC), gentamicin-ampicillin (GA), and flavored placebo (P). Antibiotics were administered orally starting on postnatal day (PND) 1 until PND 8, except for GA, which was given on PNDs 5 and 6 intramuscularly. Fecal swabs were collected from piglets on PNDs 3 and 8, and sow feces were collected 1 day after farrowing. The impacts of antibiotics on bacterial and fungal communities were assessed by sequencing the 16S rRNA and the internal transcribed spacer 2 (ITS2) rRNA genes, respectively, and quantitative PCR was performed to determine total bacterial and fungal loads. Antibiotics did not alter the α-diversity (P = 0.834) or ß-diversity (P = 0.565) of fungal communities on PND 8. AC increased the ratio of total fungal/total bacterial loads on PND 8 (P = 0.027). There was strong clustering of piglets by litter on PND 8 (P < 0.001), which corresponded to significant differences in the sow mycobiome, especially the presence of Kazachstania slooffiae. In summary, we observed a strong litter effect and showed that the maternal mycobiome is essential for shaping the piglet mycobiome in early life. IMPORTANCE This work provides evidence that although the fungal community composition is not altered by antibiotics, the overall fungal load increases with the administration of amoxicillin-clavulanic acid. Additionally, we show that the maternal fungal community is important in establishing the fungal community in piglets.