Escherichia coli F18 is mainly responsible for post-weaning diarrhea (PWD) in piglets. The molecular regulation of E. coli F18 resistance in Chinese domestic weaned piglets is still obscure. We used Meishan piglets as model animals to test their susceptibility to E. coli F18. Small RNA duodenal libraries were constructed for E. coli F18-sensitive and -resistant weaned piglets challenged with E. coli F18 and sequenced using Illumina Solexa high-throughput sequencing technology. Sequencing results showed that 3,475,231 and 37,198,259 clean reads were obtained, with 311 known miRNAs differently expressed in resistant and sensitive groups, respectively. Twenty-four miRNAs, including 15 up-regulated and 9 down-regulated, demonstrated more than a 2-fold differential expression between the F18-resistant and -sensitive piglets. Stem-loop RT-qPCR showed that miR-136, miR-196b, miR-499-5p and miR-218-3p significantly expressed in intestinal tissue (p < 0.05). KEGG pathway analysis for target genes revealed that differently expressed miRNAs were involved in infectious diseases, signal transduction and immune system pathways. Interestingly, the expression of miR-218-3p in intestinal tissue had a very significant negative correlation with target DLG5 (P < 0.01). Based on the expression correlation between miRNA and target genes analysis, we speculate that miR-218-3p targeting to DLG5, appears to be very promising candidate for miRNAs involved in response to E. coli F18 infection. The present study provides improved database information on pig miRNAs, better understanding of the genetic basis of E. coli F18 resistance in local Chinese pig breeds and lays a new foundation for identifying novel markers of E. coli F18 resistance. This article was reviewed by Neil R Smalheiser and Weixiong Zhang.

Effects of different feeding strategies on meat quality and intestinal development in pigeon squabs were investigated. 120 pairs of pigeons with two squabs each were assigned to five groups (four free-choice feeding systems and one complete feeding system): T1 (corn, pea, wheat, and pelleted feed), T2 (corn, wheat, and pelleted feed), T3 (corn, pea, and pelleted feed), T4 (corn and pelleted feed), and T5 (complete pelleted feed). Compared with T5, the diet in T4 made the breast meat redder and more yellow (p < 0.05). T2 and T4 resulted in an enhanced total superoxide dismutase activity of meat. Breast muscle in T1 and T2 was determined to have higher contents of nonessential amino acids, glycine, alanine, and glutamic acid (p < 0.05). The contents of the essential amino acids, lysine, threonine, valine, histidine, and arginine were also higher in T1 (p < 0.05). Villus height, surface area, and alkaline phosphatase activity of the duodenum and jejunum in T2 were the highest among the treatments (p < 0.05). In conclusion, free-choice feeding system can improve the meat quality and intestinal development of pigeon squabs, but which combination method of whole grains to use in the production depends on the feeding purpose.

Firstly, our research group identified Sutai pigs’ phenotypes that exhibited extreme resistance and susceptibility to the Escherichia coli F18 respectively, and then eight ETEC (Enterotoxigenic Escherichia coli) F18-resistant piglets and eight ETEC F18-sensitive piglets were selected. Then, the TAP1 (Transporter associated with antigen processing) mRNA relative expression levels were analyzed in 11 tissues of the resistant and susceptible phenotypes. Simultaneously, we detected the genetic variations in exon 3 of the TAP1 gene and evaluated the TAP1 mRNA expression levels among the different genotype pigs to study the effects of the genetic variation on gene expression, and the E. coli F18 resistance. The results revealed higher expression levels in the resistant genotypes than that in the susceptible genotypes in 11 tissues, with significant differences in the spleen, lymph node, lung, thymus, duodenum and jejunum. Furthermore, a G729A mutation was identified in the TAP1 gene exon 3, and this mutation deviates from Hardy-Weinberg equilibrium (p < 0.01). The TAP1 mRNA levels in GG genotype were significantly higher than that in the other two genotypes, with significant differences in the liver, lung, kidney, thymus, lymph node, duodenum and jejunum tissues. We speculated that high expression of the TAP1 gene might confer resistance against the E. coli F18, the G729A mutation had a significant effect on the mRNA expression, and individuals with the GG genotype possessed a stronger ability to resist the E. coli F18 infection.

Alterations in microbiota, transcript and metabolites are critical to intestinal homeostasis and host health. This study used a combination of 16s rRNA, transcriptome sequencing and liquid chromatography–mass spectrometry to investigate intestinal microbiota, genes and metabolic profiles in the ileum of Hu sheep fed broccoli extract. Here, we randomly allocated 14 Hu sheep to two diets: a basal diet without any supplementation (NC) and a basal diet supplemented with 200 mg/kg broccoli tail (BT). After 60 days of treatment, blood and jejunal samples were collected for serum biochemical indicators and multi-omics analysis. In this study, the extract of broccoli tails had a significant effect on the serum biochemical indicators, including white blood cells, red blood cells, mean corpuscular volume, mean corpuscular hemoglobin concentration, mean platelet volume, triglycerides and total protein in Hu sheep (p < 0.05). Transcriptomic analysis showed that the 672 differentially expressed genes between the NC and BT groups were primarily enriched in linoleic acid metabolism, steroid hormone biosynthesis, and cholesterol metabolism. Metabolomics analysis using Kyoto Encyclopedia of Genes and Genomes enrichment showed that the 41 differentially abundant metabolites were mainly enriched in bile secretion, vitamin B6 metabolism, and the mTOR signaling pathway. 16S rRNA sequencing results indicated that the extract of broccoli tails increased the relative abundance of Peptostreptococcaceae and decreased the relative abundance of Lachnospiraceae, Lachnospirales, and Bacteroidaceae. Integrated transcriptome, metabolome, and microbiome analysis showed that the gut microbiota and host transcriptomic changes may participate in systemic metabolic regulation by modulating amino acid metabolism, lipid signal transduction, nucleotide metabolism, and vitamin B6-related metabolic pathways. These findings demonstrate that the extract of broccoli tails modulates intestinal gene expression, systemic metabolism, and gut microbial ecology in Hu sheep, providing new insights into the utilization of agricultural byproducts as a functional feed supplement for ruminants.

Porcine circovirus type 2 (PCV2) represents a principal infectious agent causing considerable economic detriment to swine production. N-acetyltransferase 10 (NAT10), which catalyzes N⁴-acetylcytidine (ac⁴C) deposition, has been implicated in regulating immune responses, RNA stability, and viral replication. However, its role in PCV2 infection remains unclear. In this study, we established a PCV2-infected PK15 cell model and observed a marked downregulation of NAT10 expression following infection. Functional assays demonstrated that NAT10 knockdown significantly suppressed PCV2 replication in PK15 cells. Comparative transcriptomic analysis revealed that NAT10 silencing altered the expression of 81 genes, predominantly involved in immune-related signaling pathways. Notably, integrative omics analysis identified NR1H4 as a potential downstream target of NAT10. Collectively, these findings elucidate the regulatory mechanism of NAT10 in PCV2 replication and provide new insights for identifying NAT10 as a potential biomarker and therapeutic target for PCV2 infection in pigs.

Transmissible gastroenteritis virus (TGEV) represents a critical intestinal pathogen responsible for acute enteritis in pigs, posing significant challenges to global swine production biosecurity. N⁶-methyladenosine (m⁶A), the most abundant epitranscriptomic mark in eukaryotic messenger RNA, has emerged as a regulatory factor in host–virus interactions. Despite its recognized importance, the functional significance of m⁶A modifications during TGEV infection of porcine jejunal epithelial (IPEC-J2) cells remains unexplored. Here, we established a TGEV-infected IPEC-J2 cell model and we employed methylated RNA immunoprecipitation sequencing (MeRIP-seq) to comprehensively profile the m⁶A epitranscriptomic landscape and identify N⁶-methyladenosine-bearing transcripts in IPEC-J2 cells following TGEV challenge. A total of 14,813 m⁶A peaks were identified in the IPEC-J2, distributed in 7728 genes, mainly enriched in the CDS and 3′-UTRs. After TGEV infection, we identified 832 m⁶A peaks and 1660 genes with significant changes. Integrative analysis revealed a direct positive relationship between N⁶-methyladenosine modification abundance and transcript expression levels. Through integrated examination of MeRIP-Seq and RNA-Seq datasets, we identified 105 transcripts bearing m⁶A modifications, which were mainly enriched in the mTOR signaling pathway. Protein–protein interaction (PPI) network and RT-qPCR analysis demonstrated that SOS2 probably acts an important moderator in TGEV infection. This work contributes to understanding the m⁶A modification landscape in the TGEV-swine model and suggests SOS2 as potential target for future antiviral strategies.