Implications of miRNAs for animal health management in livestock remain elusive. To identify suitable miRNAs as monitoring biomarkers, piglets were randomly selected for sampling on days 0, 1, 3, 7, and 14 post-weaning. The results show that miR-10b levels in the villus upper cells of the jejunum on days 3 and 7 were significantly lower than that on day 14 post-weaning and reduced by approximately 30% on day 3 and 55% on day 7 compared to day 0. In contrast, miR-10b in crypt cells decreased by approximately 82% on day 7 and 64% on day 14 compared with day 0. Next, miR-10 knockout mice and wild-type mice were subjected to dextran sulfate sodium (DSS) for 7 days. The findings demonstrate that mice lacking miR-10b were more susceptible to DSS administration, as demonstrated by worse survival, greater weight loss, more severe tissue damage, and increased intestinal permeability. Moreover, the increased disease severity was correlated with enhanced macrophage infiltration, coincident with significantly elevated pro-inflammatory mediators and immunoglobulins. Bioinformatic analysis further reveals that the enriched pathways were mainly involved in host immune responses, and Igtp was identified as a potential target of miR-10b. These findings may provide new strategies for future interventions for swine health and production.

Background The intestinal porcine enterocyte cell line (IPEC-J2) is a well-established model to study porcine intestinal physiology. IPEC-J2 cells undergo spontaneous differentiation during culture while changes in expression patterns of differentiated IPEC-J2 remain unclear. Therefore, this study was aimed to investigate the expression profiles of IPEC-J2 cells at the transcriptional level. Differentially expressed genes (DEGs), enriched pathways and potential key genes were identified. Alkaline phosphatase (AKP) and percentages of apoptotic cells were also measured. Results Overall, a total of 988 DEGs were identified, including 704 up-regulated and 284 down-regulated genes. GO analysis revealed that epithelial cell differentiation, apoptotic signaling pathway, regulation of cytokine production and immune system process, regulation of cell death and proliferation, cell junction complexes, and kinase binding were enriched significantly. Consistently, KEGG, REACTOME, and CORUM analysis indicated that cytokine responses modulation may be involved in IPEC-J2 differentiation. Moreover, AKP activity, a recognized marker of enterocyte differentiation, was significantly increased in IPEC-J2 after 14 days of culture. Meanwhile, annexin V-FITC/PI assay demonstrated a remarkable increase in apoptotic cells after 14 days of culture. Additionally, 10 hub genes were extracted, and STAT1, AKT3, and VEGFA were speculated to play roles in IPEC-J2 differentiation. Conclusions These findings may contribute to the molecular characterization of IPEC-J2, and may progress the understanding of cellular differentiation of swine intestinal epithelium.

Background With the easy availability and competitive prices of crystalline amino acids (AAs), the reduction of dietary crude protein (CP) for pigs during early and late finisher periods is possible under commercial conditions. Two experiments were conducted to assess the growth efficiency of early and late‐finishing pigs fed with protein‐restricted diets supplemented with Lys, Met, Thr, Trp, Val, Ile and His. In Experiment 1, 840 early finishing pigs were allocated to four dietary treatments with CP levels designed at 150, 142, 134, and 126 g kg−1 diet. In Experiment 2, 768 late‐finishing pigs were allotted to four dietary treatments providing CP levels at 140, 130, 120, and 110 g kg−1 diet. Results In Experiment 1, the data showed that CP levels could be decreased from 150 to 126 g kg−1 without adversely affecting performance of early finishing pigs as no significant difference was observed for final bodyweight, average daily gain (ADG), feed to gain ratio (F:G), or average daily feed intake (ADFI). In Experiment 2, late‐finishing pigs consuming 120 g kg−1 CP tended to have the highest ADG and lowest F:G whereas those fed the 110 g kg−1 CP diet showed the opposite trend. Based on quadratic analysis, the optimum CP levels to maximize ADG and minimize F:G were 126 and 127 g kg−1, respectively. Conclusion These findings showed that dietary CP levels could be decreased to 126 g kg−1 for early finishing pigs while improved performance was noted in late‐finishing pigs consuming 120 g kg−1 CP. © 2023 Society of Chemical Industry.

Early weaning stress impairs intestinal health in piglets. miRNAs are crucial for maintaining host homeostasis, while their implication for animal health remains unclear. To identify weaning-associated miRNAs, piglets were sampled at day 0, 1, 3, 7 and 14 after weaning. The data indicated that the highest levels of miR-199a-5p in jejunal villus upper cells were observed on day 14 after weaning, while the lowest levels in crypt cells were noted on day 7 and 14. In contrast, miR-199a-3p was down-regulated in both of these two cells on day 7 after weaning compared with day 0. Both miR-199a-5p and -3p were differently expressed along the villus–crypt axis. To further clarify the function of miR-199a, mice deficient in miR-199a were exposed to dextran sulfate sodium (DSS) to induce colitis. Results revealed that silencing of miR-199a enhanced sensitivity to DSS-induced colitis. Moreover, the increased morbidity and mortality were correlated with enhanced inflammatory cell infiltration, elevated pro-inflammatory cytokine expression, impaired barrier function, and a concomitant increase in permeability-related parameters. Bioinformatic analysis further demonstrated that lipid metabolism-related pathways were significantly enriched and Ndrg1 was verified as a target of miR-199a-3p. These findings indicate that miR-199a may be important for animal health management.

Background Lysine (Lys) is the first limiting amino acid for pigs fed corn-soybean meal diets. Three experiments were conducted to estimate the optimal standardized ileal digestible (SID) Lys requirement for growing (Exp. 1), early finishing (Exp. 2), and late finishing (Exp. 3) pigs under commercial conditions. Results and conclusions In Exp. 1, a total of 650 growing pigs (32.21 ± 0.33 kg bodyweight), were allocated to 5 dietary treatments supplemented with 0.75, 0.85, 0.94, 1.03, and 1.13% SID Lys. Each treatment had 5 replicate pens with 26 pigs per pen. The lowest feed to gain ratio (F:G) was obtained by pigs fed the 1.03% Lys diet and F:G showed both a linear and a quadratic response with increasing Lys (P < 0.05). Based on broken-line and quadratic analysis models, dietary SID Lys levels for the minimum F:G were 0.94%. In Exp. 2, 650 finishing pigs (57.24 ± 2.00 kg bodyweight) were allotted to 5 dietary treatments providing SID Lys of 0.63, 0.71, 0.79, 0.87, and 0.95%. Each treatment had 5 replicates, 26 pigs per replication. The highest final bodyweight was achieved by 0.79% Lys while the highest average daily gain (ADG) and average daily feed intake (ADFI) was achieved by pigs consuming the 0.87% Lys diet (P < 0.05). Additionally, the lowest F:G was obtained by pigs fed the 0.79 and 0.87% Lys diet (P < 0.05). Based on broken-line and quadratic analysis models, the optimum Lys was 0.81 and 0.82% for ADG and F:G, respectively. In Exp. 3, 600 late finishing pigs (92.22 ± 2.41 kg bodyweight), were divided into 5 treatments providing Lys levels of 0.53, 0.60, 0.66, 0.73, and 0.79%. Each treatment had 5 replicates, 24 pigs per replication. Results showed that final bodyweight, ADG, ADFI, and F:G was not affected by increasing dietary Lys level, suggesting that the lowest SID Lys (0.53%) was sufficient for this group of pigs. Taken together, the SID Lys requirement for pigs from 30 to 60 kg, 60 to 90 kg, 90 to 120 kg was 0.94%, 0.81 to 0.82, and 0.53%, respectively, depending on the response criteria with performance maximized.