Gut Microbiota-Derived 5‑Hydroxyindoleacetic Acid Alleviates Diarrhea in Piglets via the Aryl Hydrocarbon Receptor Pathway

With the improvement in sow prolificacy, formula feeding has been increasingly used in the pig industry. Diarrhea remains a serious health concern in formula-fed (FF) piglets. Fecal microbiota transplantation (FMT) is an efficacious strategy to reshape gut microbiota and the metabolic profile for treating diarrhea. This study aims to investigate whether FMT from breast-fed piglets could alleviate diarrhea in FF piglets. The piglets were randomly assigned to the control (CON) group, FF group, and FMT group. Our results showed that FF piglets exhibited a higher diarrhea incidence, damaged colonic morphology, and disrupted barrier function. In contrast, FMT treatment normalized the morphology and barrier function. FMT suppressed the JNK/MAPK pathway and production of proinflammatory cytokines. Additionally, FF piglets had a lower abundance of the beneficial bacterial genus Bifidobacterium compared to CON piglets. Following FMT administration, Bifidobacterium was restored. Meanwhile, 5-HIAA, a metabolite of tryptophan, and AHR-responsive CYP1A1 and CYP1B1 were upregulated. Importantly, integrated multiomics analysis revealed a strong positive correlation between Bifidobacterium and 5-HIAA. In vitro, 5-HIAA supplementation reversed the LPS-induced disruption of tight junctions and production of proinflammatory cytokines in IPEC-J2 cells. In conclusion, FMT reduced diarrhea incidence and improved growth performance. The alleviative effect of FMT on diarrhea was associated with Bifidobacterium and 5-HIAA

Behavioral differences and changes in both breeds of sows 3 weeks post-parturition in the same environmental conditions.

<p>Behavioral differences and changes in both breeds of sows 3 weeks post-parturition in the same environmental conditions.</p

Table_1_Artificial rearing alters intestinal microbiota and induces inflammatory response in piglets.docx

With the ongoing genetic selection for high prolificacy in sow lines and the improvements in environment and farm management, litter size has increased in recent years. Artificial rearing is becoming widely used to raise the surplus piglets in pig industry. This study aimed to investigate the changes that happened in the morphology, microbiota, mucosal barrier function, and transcriptome caused by artificial rearing in piglet colon. Two hundred and forty newborn piglets were randomly assigned into three treatments, sow rearing until weaning (CON group), artificial rearing from day 21 (AR21 group), and artificial rearing from day 7 (AR7 group). On day 35, the piglets were euthanized to collect colon samples. The results showed that the artificially reared-piglets displayed increased pre-weaning diarrhea incidence and reduced growth performance. Artificial rearing changed the diversity and structure of colonic microbiota and increased relative abundance of harmful bacteria, such as Escherichia-Shigella. In addition, the morphological disruption was observed in AR7 group, which was coincided with decreased tight junction proteins and goblet cell numbers. Moreover, the expression of TNFSF11, TNF-α, IL-1β, TLR2, TLR4, MyD88, NF-κB, COX-2, PTGEs, iNOS, IL-2, IL-6, IL-17A, and IFN-γ was upregulated in the colon of the artificially reared-piglets, while the expression of IL-1Ra and IκBα was downregulated, indicating that artificial rearing induced inflammatory response through the activation of NF-κB pathway. Furthermore, artificial rearing regulated SLC family members, which affected solute transport and destroyed intestinal homeostasis. In conclusion, artificial rearing caused microbiota alteration, morphology disruption, the destruction of mucosal barrier function, and inflammatory response, and thus, led to subsequent increased diarrhea incidence and reduced growth performance.</p

Behavioral parameters and their definitions.

<p>Behavioral parameters and their definitions.</p

The design of the farrowing pens.

<p>The design of the farrowing pens.</p

Data_Sheet_1_Effects of short-distance transportation on physiological indexes, intestinal morphology, microbial community, and the transcriptome of the jejunum in weaned piglets.docx

Transportation of livestock is unavoidable in animal production. A total of 72 piglets were randomly divided into the CON group and the TSG group, and the piglets in CON group were transported for two hours. The purpose of this study was to determine the effects of short-distance road transportation lasting 2 h on the jejunum of weaned piglets. Our results showed that compared with the control group, there was no impact on the growth performance of piglets in the transport group (P > 0.05). The concentrations of cortisol, heat shock protein (HSP)70, HSP90, C-reactive protein, interleukin (IL)-6, IL-8, IL-12, and interferon-γ and the activity of reactive oxygen species were increased in the jejunum of piglets in the transport group (P 0.05). Regarding intestinal morphology, the transport group showed infiltration of a small amount of lymphocytes into the jejunum mucosa epithelium that was accompanied by edema of the lamina propria, whereas the control group showed no obvious abnormalities. At the genus level, in the transport group, the 16S rRNA sequencing revealed a downward trend in the relative abundance of Lactobacillus and an upward trend in the relative abundance of Muribaculaceae_unclassified. There was also increased mRNA expression of genes associated with inflammation in the transport group, but the genes and pathways related to apoptosis were not activated. In summary, weaned piglets undergoing 2 h of short-distance road transportation showed stress and inflammatory reactions of the jejunum but did not exhibit oxidative damage or activation of the apoptosis pathway of the jejunum. Furthermore, the growth performance of the piglets was not affected by the trip.</p