Evidence of vertical transmission of Senecavirus A in naturally infected sows.

Senecavirus A (SVA) is a Picornaviridae RNA virus that causes vesicular disease (VD) and transitory neonatal losses in pigs. The major ways SVA is spread are by oral, nasal, and feces. Vertical transmission of SVA was investigated during a VD epidemic in a farrow-to-finish herd in Brazil. Vesicular lesions were observed on sows before farrowing and on piglets within 24 h of birth. Analyses included RT-qPCR, viral isolation, sequencing, and virus-neutralization assays on serum, vesicular fluid, colostrum, and milk. Five out of ten sows were viremic before farrowing, and 46.7% of tested piglets had high viral loads in the first 24 h after birth. Infectious virus was detected in colostrum and milk from one postnatal sow. Despite high levels of neutralizing antibodies (nAbs) in piglet serum, colostrum, and milk, piglets were not protected from viremia and clinical illness. These findings support the vertical and congenital transmission of SVA.

Mixed Bacillus subtilis and Lactiplantibacillus plantarum-fermented feed improves gut microbiota and immunity of Bamei piglet.

Antibiotics are widely used in the breeding production of Bamei pigs, affecting the quality and safety of pork and causing enormous harm to human health, the environment, and public health. The use of probiotic fermented feed to replace antibiotic feed is one of the solutions, which has the potential to improve the intestinal microbiota, promote animal growth, and enhance immunity. The purpose of this study was to evaluate the effect of fermented feed with Lactiplantibacillus (L.) plantarum QP28-1a or Bacillus (B.) subtilis QB8a on feed, growth performance, gut microbiota, and immunity of weaned piglets. A total of 60 freshly weaned piglets from the Tibetan Plateau were randomly divided into five groups and fed basal feed, L. plantarum fermented feed, B. subtilis fermented feed, mixed fermented feed, and antibiotic fermented feed for 60 days, respectively. The results showed fermented feed supplemented with L. plantarum QP28-1a or B. subtilis QB8a significantly lowered the pH of the feed (P < 0.05), produced lactic acid and acetic acid, inhibited the growth of harmful bacteria in the feed, and reduced the feed conversion rate in the group fed mixed fermented feed (P < 0.05). The fermented feed increased the α-diversity and prominently altered the ß-diversity of the intestinal microbiota, increasing the relative abundance of beneficial bacteria such as Lactobacillus and Turicibacter and decreasing the relative abundance of conditional pathogens such as Streptococcus and Clostridium, improving the intestinal microbiota of the Bamei piglets. Notably, the mixed fermented feed improved the immunity of Bamei piglets by modulating the production of pro-inflammatory cytokines, anti-inflammatory cytokines, and inflammatory-related signaling pathways. Spearman's correlation analysis revealed that the increased expression of immune-related cytokines may be associated with a significant enrichment of Lactobacillus, Prevotellaceae, Erysipelotrichaceae, and Ruminococcaceae in the gut. In conclusion, the probiotic fermented feed maintained an acidic environment conducive to suppressing pathogens, reduced the feed conversion ratio, optimized the intestinal microbiota, improved immunity, and alleviated intestinal inflammation that may be caused by weaning, demonstrating the excellent application prospects of L. plantarum QP28-1a and B. subtilis QB8a fermented feed in the feeding of Bamei piglets.

Effects of different ratios of soluble to insoluble dietary fiber on growth performance and intestinal health of piglets.

This study investigated the impact of different ratios of soluble to insoluble dietary fiber (SDF:IDF) formulations by sugar beet pulp (SBP) supplementation on piglet growth performance, nutrient digestibility, immune function, intestinal morphology, intestinal microbiota and intestinal health. A total of 60 crossbred piglets (Duroc × [Landrace × Yorkshire]) at 40 d old with body weight of 10.0 ± 0.3 kg were randomly assigned to 5 treatments with 6 replicates per treatment and 2 piglets per replicate in a 21-d trial. The dietary treatments included a corn-soybean meal diet (0% SBP supplementation; CON), and diets supplemented with 2%, 4%, 6%, and 8% SBP, representing different SDF:IDF ratios at 10.16%, 13.53%, 16.79%, 19.86%, and 24.81%, respectively. The results indicated that the 8% SBP treatment had a negative effect on feed-to-gain ratio (linear, P = 0.009) compared with the CON treatment (P = 0.021). The apparent total tract digestibility (ATTD) of crude protein was lower in treatments supplemented with SBP (P = 0.002) and showed a linear decrease (P = 0.001), while the ATTD of IDF showed a linear increase (P = 0.037) in four SBP treatments compared to the CON treatment. The 4% SBP treatment increased serum concentrations of triglyceride (quadratic, P = 0.019) and K (linear, P < 0.0037), and decreased alanine transaminase concentration (quadratic, P = 0.015) compared with the CON treatment. The concentrations of Cit, Cys, Ile, Leu, Orn, Arg, taurine, urea, 1-methylhistidine, α-aminoadipic acid, α-aminobutyric acid and cystathionine in the 4% SBP treatment were highest among all treatments (P < 0.05). The serum concentrations of interleukin-6, interleukin-8, interleukin-10, transforming growth factor-ß, and tumor necrosis factor-α in the 6% SBP treatment were higher than those in the CON treatment (P < 0.05), which also increased mucin-2 and G protein-coupled receptor 41 mRNA expression (P < 0.05) in colonic mucosa compared with the CON treatment and improved the intestinal barrier function. Diets containing more than 19.86% SDF:IDF could impair the intestinal health in piglets when SBP was used as the SDF source. Supplementing nursery piglet diets with 16.79% to 19.86% SDF:IDF is recommended for improving intestinal barrier function, increasing short-chain fatty acids concentrations, and improving intestinal microbiota composition.

Characterization of serum proteomic and inflammatory profiling at early stage of iron deficiency in weaned piglets.

The objective of this study was to examine the early serum proteomic and inflammatory profiles of weaned piglets subjected to iron deficiency. Twelve healthy piglets (Duroc × Landrace × Large Yorkshire, body weight: 4.96 ± 0.05 kg) were weaned at 21 days of age. Subsequently, these animals were randomly allocated to one of two groups, with six replicates in each group (maintaining a male-to-female ratio of 1:1), the control group (administered 100 mg/kg Fe as FeSO4·H2O) and L-Fe group (no additional Fe supplementation). The results showed that 42 days after initiating, compared with control group, routine blood analysis revealed a reduction in serum iron content, red blood cell (RBC) count, hemoglobin (HGB) content, hematocrit (HCT), and mean corpuscular volume (MCV) (P < 0.05). Subsequent sample analysis indicated a noteworthy decrease in iron deposition in the liver, spleen, and kidneys of piglets fed the L-Fe diet compared with control group (P < 0.05). However, final body weight, average daily gain (ADG), average daily feed intake (ADFI), feed conversion ratio, and tissue coefficients were similar between the two groups (P > 0.05). During the early stages of iron deficiency, piglets exhibited increased villus height (VH) and the ratio of VH to crypt depth (CD) in the duodenum (P < 0.05) and increased expression levels of iron transporters, including duodenal cytochrome (Cybrd), divalent metal transport 1 (DMT1), and ferritin light chain (FTL) (P < 0.05). Subsequently, isobaric tags for relative and absolute quantitation (iTRAQ) were used to identify serum proteins. Gene Ontology (GO) analysis of the differentially abundant proteins (DAP) revealed that 24 of the 30 DAP were involved in platelet function, immune response, cellular metabolism, transcription, and protein synthesis. Notably, prothrombin, asporin (ASPN), and Rac family small GTPase 3 (RAC3) expression was induced, whereas glycoprotein Ib platelet subunit alpha (GPIbA) expression was decreased. This was accompanied by a substantial reduction in serum complement 3 (C3) and complement 4 (C4) contents (P < 0.05), with elevated the contents of interleukin-1ß (IL-1ß), interleukin-4 (IL-4), interleukin-6 (IL-6), transforming growth factor-ß1 (TGF-ß1), and tumor necrosis factor-α (TNF-α) (P < 0.05). Our findings underscore the essential role of dietary iron supplementation in maintaining iron homeostasis and modulating inflammatory responses in piglets.

Novel genotyping assay for a 212-kb deletion from the BBS9 gene, and frequency of the allele in pig populations in Vietnam.

Piglet lethality is one of the major concerns in pig breeding programs. Deletion of a 212-kb region within the Bardet-Biedl syndrome 9 (BBS9) gene has been linked to a reduction in the number of piglets born alive per litter. The BBS9 mutant gene carrier-by-carrier mating scheme could result in mummification of piglets carrying 2 copies of the BBS9 mutant allele, which ultimately affects the reproductive performance of the sow. Our aim was to develop a simple, rapid, and cost-efficient method that could be applied in a BBS9 mutant gene carrier screening program in low- and middle-income countries within basic laboratory settings. Here, we report an optimized multiplex PCR assay that we have established successfully for detection of a 212-kb deletion within the BBS9 genomic sequence. We genotyped 420 animals from Yorkshire, Duroc, and Landrace purebred populations in Vietnam. We found that while the BBS9 mutant allele was not identified in Duroc pigs, the frequency of BBS9 carriers was 10% in both Yorkshire and Landrace populations. We subsequently validated our results using Sanger sequencing. Our multiplex PCR method could be utilized as a BBS9 screening test in pig breeding programs.

The effect of different weaning strategies on piglet growth, feed intake and gut health.

The present study evaluated the effects of weaning strategy on piglet growth performance, onset of feed intake, and intestinal health. A total of 254 crossbred piglets were used and the experimental period lasted 45 days. The piglets were assigned to the fallowing treatments: early strategic weaning (ESW, n = 85), piglets weaned at 16 days of age and transferred to the pre-nursery unit; strategic segregated weaning (SSW, n = 85), piglets weaned at 21 days of age and kept in the farrowing crate until 24 days of age; and conventional weaning (CW, n = 84), piglet weaned at 24 days of age and transferred directly to the nursery unity; this experimental group was used as a control. Piglets from all treatments were transferred to the nursery unit at 24 days of age. For the nursery phase three periods of evaluation was considered: nursery phase I (0-7 d), nursery phase II (7-14 d), and nursery phase III (14-21 days). Piglets from the ESW and CW had greater (P < 0.001) ADG in the lactation period 16-21 days. The BW at 24 day of age was higher (P < 0.001) for piglets in the ESW and CW groups. In the nursery phase I, the ESW group had higher (P = 0.003) daily feed intake. Piglets from the ESW group had higher (P = 0.004) BW at the end of the experimental period. The ESW and SSW groups had a higher percentage of piglets (88% and 92%, respectively; P < 0,001) consuming feed in the first 24 h after transference to the nursery facility. When the total experimental period is considered, a reduction (P < 0.001) in the incidence of diarrhea was observed for ESW piglets. Overall, there was no effect of weaning strategy on intestinal permeability. In conclusion, the results of our study showed that the Segregated Strategic Weaning management can be used to mitigate the deleterious effects of early weaning.

Plant essential oils combined with organic acids restored lipopolysaccharide-induced leaky intestine via gut microbial modulation in weaned piglets.

Intestine derived lipopolysaccharide (LPS) is closely related to systemic inflammation and disorders, yet little is known about its roles in the weanling stress of piglets and its potential as a nutritional intervention target. This study aimed to investigate the potential of essential oils (EO) and organic acids (OA) in mitigating weaning stress in piglets by modulating the circulation of intestine derived LPS. Seventy-two weaned piglets at 21 d old with body weight of 8.12 ± 0.168 kg were randomly divided into a control group (CON) and an experimental group, each consisting of six pens with six piglets per pen, and were fed either a basal diet or a basal diet supplemented with 3 kg/t OA + 500 g/t EO (EO + OA). On the 14th day of the feeding trial, 12 weaned piglets were randomly selected from the CON group, and 6 piglets were selected from the experimental group. Based on diet composition and stress treatment, these 18 piglets were divided into the following three groups: 1) CON group. Piglets were fed a basal diet and received an intraperitoneal injection of saline as a control. 2) LPS group. Piglets were fed a basal diet and received an intraperitoneal injection of LPS (100 µg/kg body weight) to induce stress. 3) EO + OA + LPS group. Piglets were fed a basal diet supplemented with EO and OA and received an intraperitoneal injection of LPS (100 µg/kg body weight) to induce stress. The results showed that EO + OA significantly ameliorated the oxidative imbalance and inflammation disorder induced by LPS in piglets' serum and intestine by inhibiting the activation of the Toll-like receptor 4 (TLR4)/nuclear factor-kappa B (NF-κB)/mitogen-activated protein kinase (MAPK) signaling pathway. Furthermore, compared to the LPS group, supplementation with EO + OA restored LPS-induced reductions in Bcl-2 protein expression in the piglets' intestines (P < 0.05) and mitigated morphological damage; it also enhanced both the protein expression and relative gene expression of the tight junction proteins occludin and claudin-1 (P < 0.05), and reduced the plasma diamine oxidase activity (DAO) and LPS content (P < 0.05). Compared to the CON group, supplementation with EO + OA altered the composition of the intestinal microbiota, increasing beneficial bacteria relative abundance (Faecalibacterium) (P < 0.05) and decreasing harmful bacteria relative abundance [Rikenellaceae_RC9_gut_group (P < 0.01), Negativibacillus (P < 0.05)]. Further analysis revealed that plasma LPS content in piglets was negatively correlated with the relative abundance of Faecalibacterium (r = -0.662, P = 0.021), Akkermansia (r = -0.492, P = 0.031), and average daily gain (ADG) (r = -0.912, P = 0.041). Plasma LPS content was also positively correlated with the plasma inflammatory factors interleukin (IL)-1ß (r = 0.591, P = 0.021), IL-6 (r = 0.623, P = 0.021), IL-12 (r = 561, P = 0.031) contents, and the relative abundance of Negativibacillus (r = 0.712, P = 0.041). In summary, the addition of EO + OA prevents the leakage of intestine derived LPS into the circulation by improving intestinal integrity and microbiota composition, thereby enhancing antioxidant and anti-inflammatory abilities and growth performance of weaned piglets.

Artificial parasin I protein (API) supplementation improves growth performance and intestinal health in weaned piglets challenged with enterotoxigenic Escherichia coli.

Diarrheas are common risks faced by piglets during the weaning period. This study investigated the alleviating effects of artificial parasin I protein (API) on growth performance and intestinal health of weaned pigs upon enterotoxigenic Escherichia coli (ETEC) challenge. Sixty piglets were randomly divided into five groups and fed a basal diet (CON) or basal diet supplemented with API at 0, 750, and 1500 mg/kg or antibiotics for 5 weeks. On d 15 and 25, piglets were challenged with ETEC K88 except for the CON group. Before the ETEC challenge (d 1-14), dietary API supplementation improved growth performance, and 750 mg API increased (P < 0.05) the average daily gain (ADG), decreased (P < 0.05) feed to gain ratio (F/G) and diarrhea index of weaned piglets. ETEC challenge (during d 15-35) reduced growth performance and increased (P < 0.01) the F/G, diarrhea rate, and diarrhea index. This event was accompanied by the numerically increased malondialdehyde (MDA) levels in serum and ileum, the decreased (P < 0.05) zonula-occludens-1 (ZO-1) and interleukin-6 (IL-6) in the ileum, and the increased (P = 0.04) secretory immunoglobulin A (sIgA) protein in the ileum. Artificial parasin I protein supplementation alleviated the negative impact of ETEC. The 750 mg/kg API inclusion elevated (P < 0.05) ADG and decreased (P < 0.05) F/G. Two levels of API decreased (P < 0.01) the diarrhea rate and diarrhea index. Meanwhile, API inclusion decreased (P < 0.01) the crypt depth in the jejunum, elevated (P < 0.05) villus height in the duodenum and villus height to crypt depth ratio in the duodenum and ileum, up-regulated (P < 0.05) ZO-1 gene, and down-regulated (P < 0.05) mucin-2 gene in the jejunum, and 1500 mg/kg API decreased (P < 0.01) sIgA level and down-regulated (P < 0.05) IL-1ß gene in the ileum. Furthermore, 750 mg/kg API elevated (P < 0.01) Bifidobacteria population and acetic acid concentrations in the cecal chyme. In conclusion, API supplementation alleviates the negative impact of ETEC on growth performance and intestinal health, thus can be applied as an antibiotic alternative in weaned piglets.

Enteromorpha prolifera polysaccharide-Fe (III) complex promotes intestinal development as a new iron supplement.

Iron is a crucial micronutrient, and its deficiency can have detrimental effects on the health of infants. Dietary polysaccharide-iron (III) complexes (PICs) are promising for addressing iron deficiency due to their minimal adverse reactions and high iron absorption rate. This study aimed to investigate the effects of dietary Enteromorpha prolifera polysaccharide-Fe (III) complex (EP-Fe) on newborns, using 3-day weaned piglets as the iron-deficiency model. Results showed that EP-Fe improved iron levels and promoted intestinal development in piglets. Transcriptome sequencing revealed that EP-Fe increased the survival of intestinal epithelial cells under hypoxia by upregulating the expression of genes that promote the development of the vascular system. Additionally, EP-Fe enhanced the mucosal barrier functions by inhibiting myosin light chain kinase (MLCK)/phosphorylated myosin light chain (p-MLC) signaling pathway to increase the expression of intestinal tight junction proteins. Furthermore, the 16S rRNA gene sequencing of gut microbiota showed that EP-Fe promoted the enrichment of Bacteroides_fragilis and other gut microbes that can metabolize carbohydrates. In conclusion, EP-Fe is an effective iron supplement for newborns, and it can be developed as a comprehensive nutritional supplement.

A five domains assessment of sow welfare in a novel free farrowing system.

The Maternity Ring was developed as a free farrowing alternative to crates that preserved space whilst providing the sow with unrestricted movement. This experiment aimed to apply the Five Domains model to assess sow welfare in the Maternity Ring in comparison with the farrowing crate. Eighty-eight sows were housed in a farrowing crate (FC) and 83 in a Maternity Ring (MR), and measures collected focussed on nutrition, environment, health, behaviour, and mental state outcomes. MR sows consumed less feed than FC sows (total feed intake: 93.8 ± 3.06 kg vs. 111.2 ± 3.13 kg; p < 0.001) but had reduced P2 backfat loss during lactation (0.0 ± 0.11 vs. 1.2 ± 0.11, p < 0.001). Fewer frustrated and pain-related behaviours during farrowing were observed in MR sows (bar biting: FC 3.3 ± 2.12 vs. MR 0.5 ± 0.29 events, p = 0.038, and back leg forward: FC 227 ± 50.7 vs. MR 127 ± 26.4 events, p = 0.019), and a decreased proportion of MR sows had facial injuries after farrowing (10% CI [5, 20] vs. 67% CI [47, 95], p < 0.001). More FC sows had udder damage at weaning (70% CI [48, 97] vs. 10% CI [6, 24], p < 0.001), and their piglets were medicated more frequently when compared to those in MR (51% CI [40, 61] vs. 30% [21, 41], p = 0.008). MR sows tended to have a higher reaction score to piglet processing (MR 2.0 ± 0.38 vs. FC 1.2 ± 0.27, p = 0.094) and had more contact with piglets once the procedure was complete than FC sows (13.5 ± 2.55 vs. 6.9 ± 1.26 events, respectively, p = 0.016). Whilst there was no difference in anticipation of a feeding event (p > 0.05), MR sows displayed a reduced startle response to an aversive noise stimulus at day 18 (FC 2.8 ± 0.35, MR 0.7 ± 0.16, p < 0.001). Using the Five Domains framework, sows housed in the MR during farrowing and lactation have improved welfare than those in FC and can be thought of as being in a positive affective state.

Impact of different feed intake levels on intestinal morphology and epithelial cell differentiation in piglets.

This study aimed to investigate the effect of feed intake levels on the development of intestinal morphology and epithelial cell differentiation in piglets. Sixty-four 35-day-old healthy weaned piglets ([Large White × Landrace] × Duroc) with an initial weight (6.93 ± 0.12 kg) were randomly divided into four groups (100%, 80%, 40%, and 20% feed intake) with eight replicates of two pigs each. Samples were collected on days 3 and 7. The results revealed that with an increase in feed restriction degree and time, the body weight and organ index of piglets significantly decreased, and the villus height and crypt depth of the duodenum, jejunum, and ileum also decreased linearly (P < 0.05). After three days of feed restriction, jejunal ki67, endocrine cells, goblet cells, and villus endocrine/villus height all decreased linearly, but the villus cup/villus height ratio increased linearly, and the 40% and 20% were significantly higher than those of the 100% and 80% (P < 0.05). There was also a linear decrease in jejunal ki67, endocrine cells, goblet cells, and villous endocrine/villus height in piglets fed 7 days of food restriction; however, the villus goblet cells/villus height ratio in the 20% was significantly higher than that in the 40% group and was not different from that in the 80% (P < 0.05). During three days of feed restriction, the expression of jejunal differentiation marker genes showed a linear decreasing trend (P < 0.05), but increased linearly after seven days of feed restriction. The expression levels of interleukin17 (IL-17) and IL-22 also increased linearly (P < 0.05). KEGG and GSEA analyses indicated that the PPAR signaling pathway, ECM-receptor interaction, and Th1, Th2, and Th17 cell differentiation were significantly enriched in these processes. RT-QPCR demonstrated that both PPAR and ECM-receptor interactions were significantly activated during seven days of feeding restriction (P < 0.05). The results showed that with an increase in feed restriction intensity and time, the intestinal morphology and epithelial cell proliferation and differentiation were significantly reduced, except for the goblet cells. This phenomenon is related to the regulation of intestinal differentiation by IL-17 and IL-22 secreted by the Th cells.

Combined analysis of lncRNA and mRNA emphasizes the potential role of tryptophan-mediated regulation of muscle development in weaned piglets by lncRNA.

Pork is an important high-value protein source that fulfills the nutritional requirements for normal growth development, repair, and metabolism. Tryptophan (Trp), a crucial amino acid for piglet growth performance and muscle development, has an essential yet unclear regulatory mechanism. To investigate the biological basis of Trp regulation of piglet muscle development and identify the related regulatory pathways, we studied 20 weaned piglets. The piglets were divided into control (CON, 0.14% Trp) and high Trp (HT, 0.35% Trp) groups. They were fed with different Trp concentrations for 28 days, after which we collected the longissimus dorsi (LD) muscle for histomorphometric analysis and RNA extraction. Our results showed that the HT diet significantly increased the average daily weight gain, myocyte number, and muscle fiber density in weaned piglets. We then analyzed the differentially expressed (DE) genes in the LD muscle through RNA sequencing (RNA-seq). We identified 253 lncRNAs and 1055 mRNAs mainly involved in myoblast proliferation and myofiber formation, particularly through the FoxO and AMPK signaling pathways and metabolism. Further analysis of the DE lncRNA targeting relationship and construction of a protein-protein interaction (PPI) network resulted in the discovery of a novel lncRNA, XLOC_021675 or FRPMD, and elucidated its role in regulating piglet muscle development. Finally, we confirmed the RNA-seq results by reverse transcription polymerase chain reaction (RT-PCR). This study provides valuable insights into the regulatory mechanism of lncRNA-mediated Trp regulation of muscle development in weaned piglets offering a theoretical basis for optimizing piglet dietary ratios and enhancing pork production.

Risk factors associated with piglet pre-weaning mortality in a Midwestern U.S. swine production system from 2020 to 2022.

Piglet pre-weaning mortality (PWM) is a significant issue in the U.S. swine industry, causing economic losses and raising sustainability and animal welfare concerns. This study conducted a multivariable analysis to identify factors associated with PWM in a Midwestern U.S. swine production system. Weekly data from 47 sow farms (7207 weaning weeks) were captured from January 2020 to December 2022. Initially, 29 variables regarding farm infrastructure, productivity parameters, health status, and interventions were selected for univariate analysis to assess their association with PWM. The initial multivariable analysis included the variables with P < 0.20 in the univariate analyses. A backward stepwise model selection was conducted by excluding variables with P > 0.05, and the final multivariable model consisted of 19 significant risk factors and 6 interaction terms. The overall average PWM for the study population was 14.02 %. Yearly variations in PWM were observed, with the highest recorded in 2020 (16.61 %) and the lowest in 2021 (15.78 %). Cohorts with a pond water source, lower farrowing rate (71.9 %), higher farrowing parity (5.1), shorter gestation length (116.2 days), and using oxytocin during farrowing had increased PWM. The higher productivity parameters such as mummies rate, stillborn rate, and average total born, the higher the PWM was. Additionally, health status and intervention-related factors were associated with PWM, where higher PWM rates were observed in herds facing porcine reproductive and respiratory syndrome virus (PRRSV) outbreaks, porcine epidemic diarrhea virus (PEDV) positive, the weeks before and during feed medication, and weeks without using Rotavirus vaccine or Rotavirus feedback. Altogether, these results corroborate that PWM is a multifactorial problem, and a better understanding of the risk factors is essential in developing strategies to improve survival rates. Therefore, this study identified the major risk factors associated with PWM for groups of pigs raised under field conditions, and the results underscore the significance of data analysis in comprehending the unique challenges and opportunities inherent to each system.

Dietary xylo-oligosaccharides alleviates LPS-induced intestinal injury via endoplasmic reticulum-mitochondrial system pathway in piglets.

The beneficial effects of xylo-oligosaccharides (XOS) on the intestine have been widely reported, including anti-inflammation, antioxidant, maintenance of intestinal epithelial barrier, and treatment of intestinal injury. However, the specific mechanism of XOS in mitigating intestinal injury in weaned piglets remains unclear. Therefore, this study aimed to explore the specific mechanism of XOS in mitigating intestinal injury. The study is a complete randomized design with 24 weaned piglets in a 2 × 2 factorial arrangement that includes diet treatments (basal diet vs. 0.02% XOS) and immunological challenge [saline vs. lipopolysaccharide (LPS)]. All piglets were fed a basal diet or a XOS diet for 21 d. On day 22, all piglets received an injection of LPS or saline. In this study, dietary XOS increased jejunal villus height, reduced crypt depth and oxidative stress, and enhanced the gene and protein expression of Claudin-1, Occludin, and zonula occludens 1 (P < 0.05). The piglets fed the XOS diet had lower serum Diamine oxidase activity and d-lactic acid content (P < 0.05). In addition, dietary XOS regulates endoplasmic reticulum (ER)-mitochondria system function and the expression of key molecules, including mitochondrial dynamics dysfunction [mitofusin (Mfn)-1, optic atrophy 1, fission 1, and dynamin-related protein 1], ER stress [activating transcription factor 4 (ATF4), ATF6, C/EBP-homologous protein, eukaryotic initiation factor 2α, glucose-regulated protein (GRP) 78, GRP94, and protein kinase R-like ER kinase] and the mitochondria-associated ER membranes (MAM) disorders (Mfn2, GRP75, and voltage-dependent anion channel 1) (P < 0.05). Therefore, the findings to indicate that dietary XOS is effective against LPS-induced jejunal injury may be attributed to its ability to alleviate mitochondrial dynamics dysfunction, ER stress, and MAM disorders.

Intestinal injury can have a range of negative impacts on weaned piglets. Xylo-oligosaccharides are known for their beneficial effects on the gut, including anti-inflammatory and antioxidant properties, and also help maintain the intestinal epithelial barrier and reduce intestinal injury. However, the exact mechanism by which xylo-oligosaccharides reduce intestinal injury in piglets remains unclear. The endoplasmic reticulum­mitochondrial system, endoplasmic reticulum and mitochondria, along with the mitochondria-associated endoplasmic reticulum membranes that connect them, plays a crucial role in mediating intestinal injury in piglets. Therefore, this study aimed to investigate whether xylo-oligosaccharides affect intestinal injury in piglets through the endoplasmic reticulum, mitochondria, and the mitochondria-associated endoplasmic reticulum membranes. The results of this study indicate that xylo-oligosaccharides mitigate intestinal injury in piglets by alleviating endoplasmic reticulum stress, mitochondrial dynamics dysfunction, and mitochondria-related endoplasmic reticulum membrane disorders, providing a theoretical basis for the treatment of intestinal injury with xylo-oligosaccharides.

Flaxseed Oil Attenuates Intestinal Damage by Regulating Ferroptosis Signaling Pathway Following LPS Challenge in Piglets.

SCOPE: Ferroptosis has been demonstrated to play an important role in various tissue injuries and diseases. Flaxseed oil (FO) has been proven to have benefits for intestinal health. This study aims to explore whether FO relieved lipopolysaccharide (LPS)-induced intestinal injury through modulating ferroptosis signaling pathway. METHODS AND RESULTS: A total of 120 weaned piglets are fed diets with 3% soybean oil (SO) or 3% FO for 4 weeks. At the end of the trial, 24 piglets selected from two dietary treatment groups are used in a 2 × 2 factorial design with oil treatment (3% SO versus 3% FO) and LPS challenge (saline versus LPS). At 4 h postinjection with LPS, 24 piglets are slaughtered and intestinal samples are collected. FO improves growth performance of pigs. After LPS treatment, FO mitigates intestinal morphological damage and functional damage. Notably, FO reverses the typical ultra-morphology and biochemical indexes of ferroptosis involving glutathione, malondialdehyde, and 4-hydroxynonenal contents. Mechanistically, FO ameliorates the changes on mRNA or protein abundance of key ferroptosis signals including transferrin receptor protein 1 (TFR1), recombinant iron responsive element binding protein 2 (IREB2), FTL, HSPB1, ferritin heavy chain 1 (FTH1), ferroportin 1 (FPN1), SLC7A11, solute carrier family 3 member 2 (SLC3A2), glutathione peroxidase 4 (GPX4), and arachidonate-15-lipoxygenase (ALOX15). CONCLUSIONS: FO improves growth performance and mitigates intestinal structural and functional damage, which is involved in regulating ferroptosis signaling pathway.

Molecular Characterization and Expression of Lactoferrin Receptor (LfR) in Different Regions of the Brain Responding to Lactoferrin Intervention.

Lactoferrin (LF), an iron-binding glycoprotein rich in human milk, promotes neurodevelopment and cognition, but whether it acts through the LF receptor (LfR) and its expression profile in the brain remains unknown. We characterized 972 bp of piglet brain LfR cDNA and found LfR mRNA was expressed all brain regions being highest in the frontal lobe, followed by parietal lobe, brainstem, occipital lobe, cingulate gyrus, subventricular zone, olfactory bulb, hippocampus, amygdala, cerebellum, and thalamus. LfR mRNA and protein in different regions of the brain responded to low (155 mg/kg/day) and high (285 mg/kg/day) LF supplementation of piglets from postnatal days 3 to 38. By postnatal day 39, the low LF diet significantly increased LfR protein expression in the occipital lobe compared to controls, but not the high LF diet. LfR protein in the subventricular zone of the high LF group was 42% and 38% higher than that of the low LF group and controls, respectively. There was a trend for a dose-response relationship between LF intervention and LfR protein expression only in the prefrontal and parietal lobes. LF supplementation significantly improved piglet working memory for a difficult task, which was positively correlated with LfR protein in the prefrontal, parietal, and occipital lobes, but no dose response. Brain LfR responds to dietary LF supplementation, a mechanism by which LF can promote learning and working memory through its receptor. LfR is expressed in the whole brain, and its expression level is anatomic region specific.

Translocation of probiotics via gut-lung axis enhanced pulmonary immunity of weaned piglets exposed to low concentrations of ammonia.

OBJECTIVE: Lactobacillus salivarius is a probiotic bacteria strain in human and animal diets. The administration of probiotics to weaned piglets may improve their growth by optimizing the gastrointestinal bacterial composition. To further investigate the effect of bacterial communication between the gastrointestinal tract and lungs on bodily immunity, we reared weaned piglets in a low-ammonia gas environment. L. salivarius was supplemented to explore its effects on pulmonary immunity and its potential for bacterial translocation. RESULTS: One hundred sixty weaned piglets were allocated to four groups: L. salivarius-supplemented, L. reuteri-supplemented, control, and antibiotic drug (aureomycin)-supplemented. The feeding duration was 28 d. The body weights of piglets administered a strain of Lactobacillus were better than those of the control (P < 0.01). The transcription level of immune factors interleukin 2 (IL-2), IL-4, interferon α (IFN-α), and tumor necrosis factor α (TNF-α) in cells of the ileum and lung was significantly higher (P < 0.01). Lung and ileal mucus tissues were isolated to sequence the bacterial composition, which suggested a higher richness in the lungs at the phylum level, which was not significant in the ileum. Functional bacteria were more abundant in the ileum and lungs. The proportion of the genera of Lactobacillus, Prevotella, Actinobacillus, and Prevotellaceae_ NK3B31_group increased in two tissues, and a lower ratio of Streptococcus, Escherichia-Shigella, and mycoplasma was detected. The correlation between the microbial genus composition and the levels of immune factors suggests that the abundance of Lactobacillus plays the same positive role in the lungs and ileum. Mycoplasmas play a negative role in ileal and pulmonary immunity. More Lactobacillus reuteri and anaerobic probiotic bacteria were detected in the lungs. CONCLUSION: The colonization of Lactobacillus salivarius and Lactobacillus reuteri in the membrane of the ileum optimized the ileal microbial composition, enrolled other probiotic bacteria translating to the lung, improved the abundance of pulmonary microbiota, and enhanced immunity after exposure to low concentrations of ammonia.

Integrated Metagenomic and Metabolomics Profiling Reveals Key Gut Microbiota and Metabolites Associated with Weaning Stress in Piglets.

(1) Background: Weaning is a challenging and stressful event in the pig's life, which disrupts physiological balance and induces oxidative stress. Microbiota play a significant role during the weaning process in piglets. Therefore, this study aimed to investigate key gut microbiota and metabolites associated with weaning stress in piglets. (2) Methods: A total of ten newborn piglet littermates were randomly assigned to two groups: S (suckling normally) and W (weaned at 21 d; all euthanized at 23 d). Specimens of the cecum were dehydrated with ethanol, cleared with xylene, embedded in paraffin, and cut into 4 mm thick serial sections. After deparaffinization, the sections were stained with hematoxylin and eosin (H&E) for morphometric analysis. Cecal metagenomic and liver LC-MS-based metabolomics were employed in this study. Statistical comparisons were performed by a two-tailed Student's t-test, and p < 0.05 indicated statistical significance. (3) Results: The results showed that weaning led to intestinal morphological damage in piglets. The intestinal villi of suckling piglets were intact, closely arranged in an orderly manner, and finger-shaped, with clear contours of columnar epithelial cells. In contrast, the intestines of weaned piglets showed villous atrophy and shedding, as well as mucosal bleeding. Metagenomics and metabolomics analyses showed significant differences in composition and function between suckling and weaned piglets. The W piglets showed a decrease and increase in the relative abundance of Bacteroidetes and Proteobacteria (p < 0.05), respectively. The core cecal flora in W piglets were Campylobacter and Clostridium, while those in S piglets were Prevotella and Lactobacillus. At the phylum level, the relative abundance of Bacteroidetes significantly decreased (p < 0.05) in weaned piglets, while Proteobacteria significantly increased (p < 0.05). Significant inter-group differences were observed in pathways and glycoside hydrolases in databases, such as the KEGG and CAZymes, including fructose and mannose metabolism, salmonella infection, antifolate resistance, GH135, GH16, GH32, and GH84. We identified 757 differential metabolites between the groups through metabolomic analyses-350 upregulated and 407 downregulated (screened in positive ion mode). In negative ion mode, 541 differential metabolites were identified, with 270 upregulated and 271 downregulated. Major differential metabolites included glycerophospholipids, histidine, nitrogen metabolism, glycine, serine, threonine, ß-alanine, and primary bile acid biosynthesis. The significant differences in glycine, serine, and threonine metabolites may be potentially related to dysbiosis caused by weaning stress. Taken together, the identification of microbiome and metabolome signatures of suckling and weaned piglets has paved the way for developing health-promoting nutritional strategies, focusing on enhancing bacterial metabolite production in early life stages.

Caffeic acid modulates intestinal microbiota, alleviates inflammatory response, and enhances barrier function in a piglet model challenged with lipopolysaccharide.

Young animals are highly susceptible to intestinal damage due to incomplete intestinal development, making them vulnerable to external stimuli. Weaning stress in piglets, for instance, disrupts the balance of intestinal microbiota and metabolism, triggering intestinal inflammation and resulting in gut damage. Caffeic acid (CA), a plant polyphenol, can potentially improve intestinal health. Here, we evaluated the effects of dietary CA on the intestinal barrier and microbiota using a lipopolysaccharide (LPS)-induced intestinal damage model. Eighteen piglets were divided into three groups: control group (CON), LPS group (LPS), and CA + LPS group (CAL). On the 21st and 28th day, six piglets in each group were administered either LPS (80 µg/kg body weight; Escherichia coli O55:B5) or saline. The results showed that dietary CA improved the intestinal morphology and barrier function, and alleviated the inflammatory response. Moreover, dietary CA also improved the diversity and composition of the intestinal microbiota by increasing Lactobacillus and Terrisporobacter while reducing Romboutsia. Furthermore, the LPS challenge resulted in a decreased abundance of 14 different bile acids and acetate, which were restored to normal levels by dietary CA. Lastly, correlation analysis further revealed the potential relationship between intestinal microbiota, metabolites, and barrier function. These findings suggest that dietary CA could enhance intestinal barrier function and positively influence intestinal microbiota and its metabolites to mitigate intestinal damage in piglets. Consuming foods rich in CA may effectively reduce the incidence of intestinal diseases and promote intestinal health in piglets.

Our study focuses on a major issue affecting young animals. After weaning, piglets are particularly vulnerable to severe intestinal infections due to their immature intestinal systems, leading to damaged barriers and financial losses for the pig industry. We explore the possibility of using caffeic acid (CA), a natural compound found in plants, to promote intestinal health. Our research shows that adding CA to the diet can reduce intestinal inflammation and improve barrier function in weaned piglets challenged by lipopolysaccharide. CA positively affects ileal microbiota by increasing beneficial bacteria like Lactobacillus and Terrisporobacter and decreasing Romboutsia. We also observed differing regulatory effects of CA between the ileum and colon, with opposite changes in primary bile acids. Our findings emphasize the potential of CA as a dietary supplement to improve intestinal barrier function and modulate the inflammatory response by targeting gut microbiota and metabolites. To our knowledge, this is the first to demonstrate the effects of CA on ileal barrier function and microbiota in piglets. Our findings could significantly benefit the pig industry by mitigating financial losses from serious intestinal infections. Additionally, this research may offer key insights into the health of human infants' intestines.

Clostridium butyricum Prevents Diarrhea Incidence in Weaned Piglets Induced by Escherichia coli K88 through Rectal Bacteria-Host Metabolic Cross-Talk.

This study aimed to evaluate the effects of Clostridium butyricum (C. butyricum) on the prevention of the diarrhea rates and growth performances of weaned piglets induced by Escherichia coli K88 (E. coli K88). Twenty-four weaned piglets (6.92 ± 0.11 kg) were randomly assigned to one of three treatment groups for a period of 21 days. Each group consisted of eight pigs, with each pig being housed in an individual pen. Group I received the control diet along with normal saline, Group II received the control diet along with E. coli K88, and Group III received the control diet supplemented with 5 × 108 CFU/kg of C. butyricum and E. coli K88. We examined alterations in rectal microbiota and metabolites, analyzed the incidence of diarrhea, and investigated the interactions between microbiota and metabolites through the application of Illumina MiSeq sequencing and liquid chromatography-mass spectrometry. The results showed that, from days 14 to 21, the diarrhea incidence in Group III decreased significantly by 83.29% compared to Group II (p < 0.05). Over the entire experimental duration, the average daily feed intake of Group III decreased significantly by 11.13% compared to Group I (p < 0.05), while the diarrhea incidence in Group III decreased by 71.46% compared to Group II (p < 0.05). The predominant microbial flora in the rectum consisted of Firmicutes (57.32%), Bacteroidetes (41.03%), and Proteobacteria (0.66%). Administering E. coli K88 orally can elevate the relative abundance of Megasphaera (p < 0.05). Conversely, the supplementation of C. butyricum in the diet reduced the relative abundance of Megasphaera (p < 0.05), while increasing the relative abundance of unclassified_f_Lachnospiraceae (p < 0.05). Rectal metabolomics analysis revealed that supplementing C. butyricum in the feed significantly altered the amino acids and fatty acids of the piglets infected with E. coli K88 (p < 0.05). The correlation analysis showed that the occurrence of diarrhea was inversely related to adipic acid (p < 0.05) and positively associated with (5-hydroxyindol-3-YL) acetic acid and L-aspartic acid (p < 0.05). Prevotella_1 exhibited a negative correlation with octadecanoic acid (p < 0.05). Prevotellaceae_UCG-005 showed a negative correlation with (5-hydroxyindol-3-YL) acetic acid (p < 0.05). The findings from this research study aid in probiotic development and the enhancement of healthy growth in weaned piglets.