Berberine alleviates ETEC-induced intestinal inflammation and oxidative stress damage by optimizing intestinal microbial composition in a weaned piglet model.

Introduction: Enterotoxigenic Escherichia coli (ETEC) is the main diarrhea-causing pathogen in children and young animals and has become a global health concern. Berberine is a type of "medicine and food homology" and has a long history of use in China, particularly in treating gastrointestinal disorders and bacterial diarrhea. Methods: In this study, we explored the effects of berberine on growth performance, intestinal inflammation, oxidative damage, and intestinal microbiota in a weaned piglet model of ETEC infection. Twenty-four piglets were randomly divided into four groups-a control group (fed a basal diet [BD] and infused with saline), a BD+ETEC group (fed a basal diet and infused with ETEC), a LB+ETEC group (fed a basal diet with 0.05% berberine and infused with ETEC infection), and a HB+ETEC group (fed a basal diet with 0.1% berberine and infused with ETEC). Results: Berberine significantly improved the final body weight (BW), average daily gain (ADG), and average daily feed intake (ADFI) (P<0.05) of piglets, and effectively decreased the incidence of diarrhea among the animals (P<0.05). Additionally, berberine significantly downregulated the expression levels of the genes encoding TNF-α, IL-1ß, IL-6, IL-8, TLR4, MyD88, NF-κB, IKKα, and IKKß in the small intestine of piglets (P<0.05). ETEC infection significantly upregulated the expression of genes coding for Nrf2, CAT, SOD1, GPX1, GST, NQO1, HO-1, GCLC, and GCLM in the small intestine of the animals (P<0.05). Berberine significantly upregulated 12 functional COG categories and 7 KEGG signaling pathways. A correlation analysis showed that berberine significantly increased the relative abundance of beneficial bacteria (Gemmiger, Pediococcus, Levilactobacillus, Clostridium, Lactiplantibacillus, Weissella, Enterococcus, Blautia, and Butyricicoccus) and decreased that of pathogenic bacteria (Prevotella, Streptococcus, Parabacteroides, Flavonifractor, Alloprevotella) known to be closely related to intestinal inflammation and oxidative stress in piglets. In conclusion, ETEC infection disrupted the intestinal microbiota in weaned piglets, upregulating the TLR4/MyD88/NF-κB and Nrf2 signaling pathways, and consequently leading to intestinal inflammation and oxidative stress-induced damage. Discussion: Our data indicated that berberine can optimize intestinal microbiota balance and modulate the TLR4/MyD88/NF-κB and Nrf2 signaling pathways, thus helping to alleviate intestinal inflammation and oxidative damage caused by ETEC infection in weaned piglets.

Diagnostic utility of acute phase proteins and their ability to guide antibiotic usage in pigs, horses, and cattle: a mapping review.

To mitigate the use of antibiotics for many of the multifactorial diseases seen in pigs, horses and cattle, new diagnostic tools are needed. Acute phase protein (APP) measurements can, in humans, be used to guide antibiotic treatment initiation, evaluate treatment efficacy, and make a prognosis. The aim of this review is to collect evidence on the clinical functionality of APP measurements as a tool to guide antibiotic treatment in pigs, horses, and cattle. Literature was retrieved using Medline, CAB Abstracts and Google Scholar. The acute phase response has been investigated for a plethora of diseases and clinical signs and the major acute phase proteins are elevated in diseased compared to healthy animals. Few studies correlated acute phase response with aetiology, antibiotic treatment efficacy, prognosis, or severity of disease. The existing research does not support that APP can be used to guide antibiotic treatment, but the reported studies indicate that C-reactive protein (CRP) might be able to differentiate between bacterial and non-bacterial causes of disease in pigs. Serum amyloid A (SAA) might reflect underlying aetiology in horses and infectious or non-infectious cases of mastitis in cows.

The Mechanism of Zinc Oxide in Alleviating Diarrhea in Piglets after Weaning: A Review from the Perspective of Intestinal Barrier Function.

Weaning is one of the most challenging phases for piglets, and it is also the time when piglets are the most susceptible to diarrhea, which may result in significant economic losses for pig production. One of the dietary strategies for reducing post-weaning diarrhea (PWD) in piglets is to provide them with a pharmacological dose of zinc oxide (ZnO). However, excessive or long-term usage of high-dose ZnO has significant impacts on pig health and the ecological environment. Therefore, caution should be exercised when considering the use of high-dose ZnO for the prevention or treatment of PWD in piglets. In this paper, the significant role of zinc in animal health, the potential mode of action of ZnO in alleviating diarrhea, and the impact of innovative, highly efficient ZnO alternatives on the regulation of piglet diarrhea were reviewed to offer insights into the application of novel ZnO in pig production.

Integrating network pharmacology with pharmacological research to elucidate the mechanism of modified Gegen Qinlian Decoction in treating porcine epidemic diarrhea.

Porcine Epidemic Diarrhea Virus (PEDV) poses a significant threat to neonatal piglets, particularly due to the limited efficacy of existing vaccines and the scarcity of efficacious therapeutic drugs. Gegen Qinlian Decoction (GQD) has been employed for over two millennia in treating infectious diarrhea. Nonetheless, further scrutiny is required to improve the drug's efficacy and elucidate its underlying mechanisms of action. In this study, a modified GQD (MGQD) was developed and demonstrated its capacity to inhibit the replication of PEDV. Animal trials indicated that MGQD effectively alleviated pathological damage in immune tissues and modulated T-lymphocyte subsets. The integration of network analysis with UHPLC-MS/MS facilitated the identification of active ingredients within MGQD and elucidated the molecular mechanisms underlying its therapeutic effects against PEDV infections. In vitro studies revealed that MGQD significantly impeded PEDV proliferation in IPEC-J2 cells, promoting cellular growth via virucidal activity, inhibition of viral attachment, and disruption of viral biosynthesis. Furthermore, MGQD treatment led to increased expression levels of IFN-α, IFN-ß, and IFN-λ3, while concurrently decreasing the expression of TNF-α, thereby enhancing resistance to PEDV infection in IPEC-J2 cells. In conclusion, our findings suggest that MGQD holds promise as a novel antiviral agent for the treatment of PEDV infections.

The Mechanism of Action of the Active Ingredients of Coptidis rhizoma against Porcine Epidemic Diarrhea Was Investigated Using Network Pharmacology and Molecular Docking Technology.

The objective of this study was to elucidate the mechanism of action of the active components of Coptidis rhizoma against porcine epidemic diarrhea and to provide a theoretical foundation for further development of novel anti-PED therapeutic agents based on Coptidis rhizoma. The potential targets of Coptidis rhizoma against PEDV were identified through a comprehensive literature review and analysis using the TCMSP pharmacological database, SwissDrugDesign database, GeneCards database, and UniProt database. Subsequently, the STRING database and Cytoscape 3.7.1 software were employed to construct a protein-protein interaction (PPI) network and screen key targets. Gene Ontology (GO) function and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis were conducted on the identified targets. Molecular docking studies were performed using AutoDock 1.5.7 software to analyze the binding energy and modes of interaction between the active components of Coptidis rhizoma and the target proteins. The PyMOL 2.5.0a0 software was employed to visualize the docking results. Through comprehensive analysis, 74 specific targets of active components of Coptidis rhizoma against PEDV were identified. The core gene targets were screened, and an interaction network diagram was subsequently generated. Ultimately, 14 core targets were identified, with STAT3, ESR1, CASP3, and SRC exhibiting the most significant interactions. GO enrichment analysis revealed a total of 215 molecular items, including 48 biological function items, 139 biological process items, and 28 cellular component items. KEGG enrichment analysis identified 140 signaling pathways. Molecular docking analysis demonstrated that epiberberine and palmatine exhibited high binding affinity with STAT3 protein, worenine showed high binding affinity with ESR1 protein, obacunone exhibited high binding affinity with CASP3 protein, and epiberberine, obacunone, berberine, and berberruine exhibited high binding affinity with SRC protein. A network pharmacology and molecular docking technology approach was employed to screen six important active components of Coptidis rhizoma and four important potential targets against PEDV infection. The findings indicated that the active components of Coptidis rhizoma could serve as promising pharmaceutical agents for the prevention and control of PEDV, with significant potential for clinical application.

Gut microbiome perturbation and its correlation with tylosin pharmacokinetics in healthy and infected pigs.

Tylosin, an antibiotic with a long history in treating respiratory bacterial infections, has unknown effects on the gut microbiota of healthy and infected pigs. The study aimed to investigate the effect of a therapeutic dose of tylosin on swine gut microbiota and explored the relationship between this effect and tylosin pharmacokinetics (PK). We also assessed whether changes in gut microbiota after tylosin administration differ between healthy animals (n = 7) and animals intranasally co-infected (n = 7) with Actinobacillus pleuropneumoniae and Pasteurella multocida. Both groups were intramuscularly administered with tylosin (20 mg/kg). The 16S rRNA gene analyses revealed a significantly lower species richness and diversity, after tylosin treatment, in the infected than the healthy pigs, with infected pigs having lower levels of Bacteroidetes and Firmicutes and higher levels of Proteobacteria. Greater tylosin exposure (greater area under curve (AUC) and maximum plasma concentration (Cmax), and slower elimination (longer terminal half-life, T1/2) were observed in healthy than infected pigs. Relative abundance of Lactobacillus, Oscillibacter, Prevotella, and Sporobacter was positively and significantly correlated with AUC and Cmax, whereas the abundance of Acinetobacter, Alishewanella, and Pseudomonas was positively and significantly correlated with T1/2 and mean residence time (MRT) of tylosin. Our findings, for the first time, demonstrated significant changes in swine gut microbiota after a single therapeutic dose of tylosin was administered, whereas the effect of these changes on tylosin PK was not evident.

Quercetin Increases Growth Performance and Decreases Incidence of Diarrhea and Mechanism of Action in Weaned Piglets.

This study aimed to investigate the mechanism of quercetin increasing growth performance and decreasing incidence of diarrhea in weaned piglets. Forty-eight Duroc × Landrace × Large White weaned piglets with similar body weight (7.48 ± 0.20 kg, 28 days of age) were randomly divided into four treatments (control, 250 mg/kg quercetin, 500 mg/kg quercetin, and 750 mg/kg quercetin treatments) and fed with basal diet or experimental diet supplemented with quercetin. Performance, diarrhea rate and index, and content of serum anti-inflammatory factors were determined and calculated in weaned piglets; colonic flora and signaling pathways related to anti-inflammation were measured using 16S rDNA sequencing and RNA-seq, respectively. The results showed that compared with control, feed-to-gain ratio and content of serum interferon gamma (IFN-γ) were significantly decreased in the 500 and 750 mg/kg quercetin treatments (P < 0.05); quercetin significantly decreased diarrhea rate and diarrhea index (P < 0.05) and significantly increased the content of serum transforming growth factor (TGF-ß) in weaned piglets (P < 0.05); the content of serum NF-κB was significantly decreased in the 750 mg/kg quercetin treatment (P < 0.05); moreover, quercetin significantly increased diversity of colonic flora (P < 0.05), and at the phylum level, the relative abundance of Actinobacteria in the 500 and 750 mg/kg treatments was significantly increased (P < 0.05), and the relative abundance of Proteobacteria in the three quercetin treatments were significantly decreased (P < 0.05) in the colon of weaned piglets; at the genus level, the relative abundance of Clostridium-sensu-stricto-1, Turicibacter, unclassified_f_Lachnospiraceae, Phascolarctobacterium, and Family_XIII _AD3011_group was significantly increased (P < 0.05); the relative abundance of Subdollgranulum and Blautia was significantly decreased in the 500 and 750 mg/kg treatments (P < 0.05); the relative abundance of Eschericha-Shigella, Terrisporobacter, and Eubacterium-coprostanoligenes was significantly increased (P < 0.05); the relative abundance of Streptocococcus, Sarcina, Staphylococcus, and Ruminococcaceae_UCG-008 was significantly decreased in the three quercetin treatments (P < 0.05); the relative abundance of Ruminococcaceae_UCG_014 was significantly increased in the 250 mg/kg quercetin treatment in the colon of weaned piglets (P < 0.05). The results of Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis showed that differentially expressed genes (DEGs) from the quercetin treatments were significantly enriched in nuclear transcription factor-κB (NF-κB) signal pathway (P < 0.05); mRNA expression of tumor necrosis factor-α (TNF-α), interleukin-1R1 (IL-1R1), conserved helix-loop-helix ubiquitous kinase (CHUK), toll-like receptor 4 (TLR4), and IL-1ß from quercetin treatments were significantly decreased in colonic mucosa of weaned piglets (P < 0.05). In summary, quercetin increased feed conversion ratio and decreased diarrhea through regulating NF-κB signaling pathway, controlling the balance between anti-inflammatory and proinflammatory factors, and modulating intestinal flora, thus promoting the absorption of nutrients in weaned piglets. These results provided the theoretical foundation for applying quercetin in preventing weaning piglets' diarrhea and animal husbandry practices.

Protective effect of dihydromyricetin on intestinal epithelium in weaned pigs upon enterotoxigenic Escherichia coli challenge.

Dihydromyricetin (DMY), a natural flavonoid compound, are believed to prevent inflammatory response, dealing with pathogens and repairing the intestinal barrier. The objective of this study was to investigate whether DMY supplementation could attenuate intestinal damage in the context of enterotoxigenic Escherichia coli K88 (ETEC F4+) infection. After weaning, different litters of pigs were randomly assigned to one of the following treatments: (1) non-challenged control (CON, fed with basal diet); (2) ETEC-challenged control (ECON, fed with basal diet); and (3) ETEC challenge + DMY treatment (EDMY, fed with basal diet plus 300 mg kg-1 DMY). We observed a significant reduction in fecal Escherichia coli shedding and diarrhea incidence, but an increase in ADG in pigs of EDMY group compared to the pigs of ECON group. Relative to the pigs of ECON group, dietary DMY treatment decreased (P < 0.05) concentrations of the serum D-xylose, D-lactate and diamine oxidase (DAO), but increased the abundance of zonula occludens-1 (ZO-1) in the jejunum of pigs. In addition, DMY also decreased (P < 0.05) the number of S-phase cells and the percentage of total apoptotic epithelial cells of jejunal epithelium in pigs of the EDMY group compared to the pigs of the ECON group. Furthermore, DMY decreased the mRNA expression levels of critical immune-associated genes TLR4, NFκB, Caspase3, Caspase9, IL-1ß, IL-6, TNF-α and the protein p-NFκB and p-IκBα expressions of intestinal epithelium in pigs of the EDMY group compared to the pigs of the ECON group. Compared to the ECON group, DMY elevated (P < 0.05) the expression levels of ß-defensins PBD1, PBD2, PBD3, PBD129, as well as the abundance of secreted IgA in intestinal mucosae of the EDMY group. Thus, our results indicate that DMY may relieve intestinal integrity damage due to Escherichia coli F4.

Therapeutic effects of mitoquinol during an acute heat stress challenge in growing gilts.

Study objectives were to evaluate the effects of mitoquinol (MitoQ) on production parameters, gastrointestinal tract (GIT; stomach and small and large intestines) weight, and circulating leukocytes during a 24-h acute heat stress (HS) challenge. Crossbred gilts [n = 32; 49.1 ±â€…2.4 kg body weight (BW)] were blocked by BW and randomly assigned to 1 of 4 environmental-therapeutic treatments: 1) thermoneutral (TN) control (n = 8; TNCON), 2) TN and MitoQ (n = 8; TNMitoQ), 3) HS control (n = 8; HSCON), or 4) HS and MitoQ (n = 8; HSMitoQ). Pigs were moved into individual pens and allowed to acclimate for 6 d. The study consisted of 2 experimental periods (P). During P1 (2 d), all pigs remained in TN conditions (20.6 ±â€…1.5 °C) and were fed ad libitum. During P2 (24 h), pigs were fed ad libitum and exposed to either TN or constant HS (37.3 ±â€…1.3 °C). Mitoquinol (40 mg/d) was orally administered twice daily (0700 and 1800 hours) during P1 and P2. As expected, pigs exposed to HS had increased rectal temperature, skin temperature, and respiration rate (+1.5 °C, +8.7 °C, and +86 bpm, respectively; P < 0.01) compared to their TN counterparts. Compared to TN, HS pigs had decreased feed intake (67%; P < 0.01) and significant BW loss (+1.5 vs. -1.9 kg, respectively; P < 0.01). Total GIT weight was decreased in HS relative to TN pigs (P < 0.01), and this was influenced by decreased luminal contents (2.43 vs. 3.26 kg, respectively; P < 0.01) and reduced empty GIT mass (3.21 vs. 3.48 kg, respectively; P = 0.03). Stomach contents remained similar between TN and HS pigs (P > 0.54) but tended to increase in MitoQ relative to CON pigs (0.90 vs. 0.63 kg, respectively; P = 0.08). Stomach content as a percentage of the previous 24 h feed intake was increased in HS compared to the TN controls (93% vs. 31%; P < 0.01). In contrast, small and large intestinal contents were decreased in HS compared to TN pigs (23% and 49%, respectively; P < 0.01). Liver weight decreased in HS relative to TN pigs (1.15 vs. 1.22 kg, respectively; P = 0.02), and was decreased in MitoQ compared to CON pigs (1.13 vs. 1.24 kg; P < 0.01). Circulating lymphocytes tended to be decreased in HS relative to TN pigs (16%; P = 0.07). In summary, acute HS increased all body temperature indices, negatively influenced animal performance, and differentially altered GIT motility as evidenced by decreased gastric emptying and increased intestinal transit. However, MitoQ supplementation did not appear to ameliorate these effects.

Heat stress (HS) causes enormous financial losses to animal agriculture due to its adverse effects on animal productivity. While the mechanisms behind HS-induced malaise are multifaceted and intricate, evidence points to intestinal barrier dysfunction and the ensuing immune response as a primary contributor. Presumably, HS induces oxidative stress (OS) within the intestinal epithelium, potentially leading to intestinal hyperpermeability. Mitochondria are the primary source of endogenous reactive oxygen species; thus, administering mitochondria-targeted antioxidants, such as mitoquinol (MitoQ), may be more effective at reducing OS than traditional dietary antioxidants (e.g., vitamin E, selenium). We have previously observed positive effects of MitoQ on growth performance in acutely heat-stressed barrows, which prompted our objective to determine if the results were repeatable with gilts. Herein, HS increased all body temperature indices, reduced feed intake, and caused severe body weight loss. Additionally, HS reduced gastrointestinal tract (GIT) weight and differentially altered GIT luminal contents, suggesting HS disparately affects GIT motility. However, contrary to our expectations, MitoQ did not alleviate these physiological and phenotypic responses to HS. Altogether, the beneficial results from our previous MitoQ experiment in barrows were not repeatable in gilts, and it remains unclear whether supplementing antioxidants during HS is beneficial for animal performance.

Prostaglandin E2 is an unreliable biomarker for inflammation in castrated piglets: a randomized controlled trial assessing pharmaceutical drug efficiency.

OBJECTIVE: To investigate the effect of intranasal (IN) flunixin meglumine (FM) and intra-inguinal (IG) lidocaine on castration inflammation using prostaglandin E2 (PGE2) concentration as a biomarker. METHODS: This randomized controlled trial was conducted in March 2022. Blood was collected at -24, 1, and 24 hours postcastration for PGE2 quantification from 195 piglets that received 1 of 8 treatments: (1) saline (1.5 mL) applied IG and IN (0.2 mL) followed by surgical castration (n = 24); (2) saline (1.5 mL) IG and IN (0.2 mL) followed by sham castration (25); (3) lidocaine (20 mg/kg or 1.5 mL) IG followed by surgical castration (24); (4) lidocaine (20 mg/kg or 1.5 mL) IG followed by sham castration (25); (5) FM (2.2 mg/kg) IN followed by surgical castration (25); (6) FM (2.2 mg/kg) IN followed by sham castration (24); (7) lidocaine (20 mg/kg or 1.5 mL) IG and FM (2.2 mg/kg) IN followed by surgical castration (24); and (8) lidocaine (20 mg/kg or 1.5 mL) IG and FM (2.2 mg/kg) IN followed by sham castration (24). RESULTS: Prostaglandin E2 concentrations did not increase following the castration procedure and were not an effective biomarker of castration inflammation. Piglets that received lidocaine demonstrated no difference in PGE2 levels across all time points. Piglets administered FM had lower PGE2 concentrations at 1 hour and 20 minutes postdrug administration in both the sham and castrated piglets. CONCLUSIONS: Prostaglandin E2 was not an effective biomarker to quantify castration inflammation. Flunixin meglumine was able to reduce PGE2 concentration in piglets regardless of castration procedure, but lidocaine had no impact. Decreased PGE2 levels in FM-treated pigs are likely associated with the drug's ability to mitigate a noncastration-associated inflammatory process occurring independent of the castration procedure. CLINICAL RELEVANCE: Flunixin meglumine reduced circulating PGE2 concentration in the blood, regardless of the castration procedure, indicating a potential for the drug to mitigate an inflammatory process unrelated to castration.

Recombinant porcine interferon delta 8 inhibits swine acute diarrhoea syndrome coronavirus infection in vitro and in vivo.

Swine acute diarrhoea syndrome coronavirus (SADS-CoV), which originates from zoonotic transmission of bat coronaviruses in the HKU2 lineage, causes severe illness in pigs and carries a high risk of spreading to humans. At present, there are no licenced therapeutics for the treatment of SADS-CoV. In this study, we examined the effectiveness of recombinant porcine interferon delta 8 (IFN-δ8) against SADS-CoV both in vitro and in vivo. In vitro experiments showed that IFN-δ8 inhibited SADS-CoV proliferation in a concentration-dependent manner, with complete inhibition occurring at a concentration of 5 µg/mL. In vivo experiments demonstrated that two 50 µg/kg doses of IFN-δ8 injected intraperitoneally protected piglets against lethal challenge, blocked viral shedding, attenuated intestinal damage, and decreased the viral load in the jejunum and ileum. Further findings suggested that IFN-δ8 inhibited SADS-CoV infection by increasing the expression of IFN-stimulated genes. These results indicate that IFN-δ8 shows promise as a biological macromolecule drug against SADS-CoV infection.

Antiviral activity of luteolin against porcine epidemic diarrhea virus in silico and in vitro.

BACKGROUND: Porcine epidemic diarrhea virus (PEDV) mainly causes acute and severe porcine epidemic diarrhea (PED), and is highly fatal in neonatal piglets. No reliable therapeutics against the infection exist, which poses a major global health issue for piglets. Luteolin is a flavonoid with anti-viral activity toward several viruses. RESULTS: We evaluated anti-viral effects of luteolin in PEDV-infected Vero and IPEC-J2 cells, and identified IC50 values of 23.87 µM and 68.5 µM, respectively. And found PEDV internalization, replication and release were significantly reduced upon luteolin treatment. As luteolin could bind to human ACE2 and SARS-CoV-2 main protease (Mpro) to contribute viral entry, we first identified that luteolin shares the same core binding site on pACE2 with PEDV-S by molecular docking and exhibited positive pACE2 binding with an affinity constant of 71.6 µM at dose-dependent increases by surface plasmon resonance (SPR) assay. However, pACE2 was incapable of binding to PEDV-S1. Therefore, luteolin inhibited PEDV internalization independent of PEDV-S binding to pACE2. Moreover, luteolin was firmly embedded in the groove of active pocket of Mpro in a three-dimensional docking model, and fluorescence resonance energy transfer (FRET) assays confirmed that luteolin inhibited PEDV Mpro activity. In addition, we also observed PEDV-induced pro-inflammatory cytokine inhibition and Nrf2-induced HO-1 expression. Finally, a drug resistant mutant was isolated after 10 cell culture passages concomitant with increasing luteolin concentrations, with reduced PEDV susceptibility to luteolin identified at passage 10. CONCLUSIONS: Our results push forward that anti-PEDV mechanisms and resistant-PEDV properties for luteolin, which may be used to combat PED.

Antimicrobial use on pig farms in Thailand: Farmer perceptions of use and resistance.

Limiting the use of antimicrobial agents in intensive livestock production is a challenge due to different perceptions between the short-term benefits of antimicrobial use (AMU) by livestock producers and the long-term social costs of antimicrobial resistance (AMR) and its impact on human, animal, and environmental health. Pig farmers are key stakeholders supporting Thailand's national strategic plan on AMR which aims to reduce antimicrobial consumption in the livestock sector. Consequently, this study explored the knowledge, perceptions, attitudes, and practices of pig farmers towards AMU and AMR, expecting to provide information that would help guide policymakers in the development of a proper interventional program for antimicrobial stewardship. The qualitative approach utilized individual, face-to-face, in-depth, semi-structured interviews with the 20 owners of middle- and large-scale pig farms in eastern Thailand. The major themes identified in this finding were: (1) the use of antimicrobials on farms and the knowledge of antimicrobials; (2) AMU on pig farms (the purpose of AMU, antimicrobial prescription practices, and performing antimicrobial susceptibility testing); (3) attitudes towards prescribing practices and record keeping; (4) farm animal husbandry practices and AMU; (5) factors influencing AMU; and (6) awareness regarding AMR. Most of the pig farm owners recognized that achieving Good Agricultural Practices certification required following the legislation and regulations for AMU. Other observations were that the respondents had positive attitudes towards prescribing practices, performing antimicrobial susceptibility testing before antimicrobial therapy, and recording drug use on farms; however, there was low awareness of AMR. In addition, alternative substances, such as medicinal plants, and proper biosecurity practices were mentioned. Factors influencing AMU on pig farms were intensive enforcement of legislation and regulations, the implementation of farm management practices, the provision of information and consultancy services by veterinary professionals, farmer experience, and consumer trends.

Baicalin attenuates PD-1/PD-L1 axis-induced immunosuppression in piglets challenged with Glaesserella parasuis by inhibiting the PI3K/Akt/mTOR and RAS/MEK/ERK signalling pathways.

Infection of piglets with Glaesserella parasuis (G. parasuis) induces host immunosuppression. However, the mechanism underlying the immunosuppression of piglets remains unclear. Activation of the PD-1/PD-L1 axis has been shown to trigger host immunosuppression. Baicalin possesses anti-inflammatory and immunomodulatory functions. However, whether baicalin inhibits PD-1/PD-L1 activation and thus alleviates host immunosuppression has not been investigated. In this study, the effect of baicalin on the attenuation of piglet immunosuppression induced by G. parasuis was evaluated. Seventy piglets were randomly divided into the control group, infection group, levamisole group, BMS-1 group, 25 mg/kg baicalin group, 50 mg/kg baicalin group and 100 mg/kg baicalin group. Following pretreatment with levamisole, BMS-1 or baicalin, the piglets were challenged with 1 × 108 CFU of G. parasuis. Our results showed that baicalin, levamisole and BMS-1 modified routine blood indicators and biochemical parameters; downregulated IL-1ß, IL-10, IL-18, TNF-α and IFN-γ mRNA expression; and upregulated IL-2 and IL-8 mRNA expression in blood. Baicalin, levamisole and BMS-1 increased the proportions of CD3+ T cells, CD3+CD4+ T cells, CD3+CD8+ T cells and CD3-CD21+ B cells in the splenocyte population, increased the proportions of CD3+ T cells, CD3+CD4+ T cells and CD3+CD8+ T cells in the blood, and inhibited PD-1/PD-L1 and TIM-3 activation. Baicalin, levamisole and BMS-1 reduced p-PI3K, p-Akt, and p-mTOR expression, the p-MEK1/2/MEK1/2 and p-ERK1/2/ERK1/2 ratios and increased RAS expression. Baicalin, levamisole and BMS-1 provided substantial protection against G. parasuis challenge and relieved tissue histopathological damage. Our findings might provide new strategies for controlling G. parasuis infection and other immunosuppressive diseases.

PA-824 inhibits porcine epidemic diarrhea virus infection in vivo and in vitro by inhibiting p53 activation.

Porcine epidemic diarrhea virus (PEDV) is a type A coronavirus that causes severe watery diarrhea in piglets, resulting in severe economic losses worldwide. Therefore, new approaches to control PEDV infection are essential for a robust and sustainable pig industry. We screened 314 small-molecule drug libraries provided by Selleck and found that four drugs had obviously inhibitory effects on PEDV in Vero cells. PA-824, which had the highest SI index and the most reliable clinical safety, was selected for in vivo experiments. Animal attack tests showed that PA-824 effectively alleviated the clinical signs, intestinal pathological changes, and inflammatory responses in lactating piglets after PEDV infection. To further investigate the antiviral mechanism of PA-824, we measured the inhibitory effect of PA-824 on PEDV proliferation in a dose-dependent manner. By exploring the effect of PA-824 on the PEDV life cycle, we found that PA-824 acted directly on viral particles and hindered the adsorption, internalization, and replication phases of the virus, followed by molecular docking analysis to predict the interaction between PA-824 and PEDV non-structural proteins. Finally, we found that PA-824 could inhibit the apoptotic signaling pathway by suppressing PEDV-induced p53 activation. These results suggest that PA-824 could be protective against PEDV infection in piglets and could be developed as a drug or a feed additive to prevent and control PEDV diseases.IMPORTANCEPEDV is a highly contagious enteric coronavirus that widely spread worldwide, causing serious economic losses. There is no drug or vaccine to effectively control PEDV. In this study, we found that PA-824, a compound of mycobacteria causing pulmonary diseases, inhibited PEDV proliferation in both in vitro and in vivo. We also found that PA-824 directly acted on viral particles and hindered the adsorption, internalization, and replication stages of the virus. In addition, we found that PA-824 could inhibit the apoptotic signaling pathway by inhibiting PEDV-induced p53 activation. In conclusion, it is expected to be developed as a drug or a feed additive to prevent and control PEDV diseases.

Therapeutic effects of mitoquinol during an acute heat stress challenge in growing barrows.

Study objectives were to determine the effects of mitoquinol (MitoQ, a mitochondrial-targeted antioxidant) on biomarkers of metabolism and inflammation during acute heat stress (HS). Crossbred barrows [n = 32; 59.0 ±â€…5.6 kg body weight (BW)] were blocked by BW and randomly assigned to 1 of 4 environmental-therapeutic treatments: 1) thermoneutral (TN) control (n = 8; TNCon), 2) TN and MitoQ (n = 8; TNMitoQ), 3) HS control (n = 8; HSCon), or 4) HS and MitoQ (n = 8; HSMitoQ). Pigs were acclimated for 6 d to individual pens before study initiation. The trial consisted of two experimental periods (P). During P1 (2 d), pigs were fed ad libitum and housed in TN conditions (20.6 ±â€…0.8 °C). During P2 (24 h), HSCon and HSMitoQ pigs were exposed to continuous HS (35.2 ±â€…0.2 °C), while TNCon and TNMitoQ remained in TN conditions. MitoQ (40 mg/d) was orally administered twice daily (0700 and 1800 hours) during P1 and P2. Pigs exposed to HS had increased rectal temperature, skin temperature, and respiration rate (+1.5 °C, +6.8 °C, and +101 breaths per minute, respectively; P < 0.01) compared to their TN counterparts. Acute HS markedly decreased feed intake (FI; 67%; P < 0.01); however, FI tended to be increased in HSMitoQ relative to HSCon pigs (1.5 kg vs. 0.9 kg, respectively; P = 0.08). Heat-stressed pigs lost BW compared to their TN counterparts (-4.7 kg vs. +1.6 kg, respectively; P < 0.01); however, the reduction in BW was attenuated in HSMitoQ compared to HSCon pigs (-3.9 kg vs. -5.5 kg, respectively; P < 0.01). Total gastrointestinal tract weight (empty tissue and luminal contents) was decreased in HS pigs relative to their TN counterparts (6.2 kg vs. 8.6 kg, respectively; P < 0.01). Blood glucose increased in HSMitoQ relative to HSCon pigs (15%; P = 0.04). Circulating non-esterified fatty acids (NEFA) increased in HS compared to TN pigs (P < 0.01), although this difference was disproportionately influenced by elevated NEFA in HSCon relative to HSMitoQ pigs (251 µEq/L vs. 142 µEq/L; P < 0.01). Heat-stressed pigs had decreased circulating insulin relative to their TN counterparts (47%; P = 0.04); however, the insulin:FI ratio tended to increase in HS relative to TN pigs (P = 0.09). Overall, circulating leukocytes were similar across treatments (P > 0.10). Plasma C-reactive protein remained similar among treatments; however, haptoglobin increased in HS relative to TN pigs (48%; P = 0.03). In conclusion, acute HS exposure negatively altered animal performance, inflammation, and metabolism, which were partially ameliorated by MitoQ.

Heat stress (HS) compromises animal health and productivity, and this causes major economic losses in almost every livestock sector. The negative consequences of HS are thought to originate from intestinal barrier dysfunction and subsequent immune activation. The underlying causes of lost intestinal integrity during HS are likely multifactorial; however, intestinal ischemia, increased accumulation of reactive oxygen species, and the ensuing epithelial oxidative damage might be potential causes. Mitochondria-targeted antioxidants, such as mitoquinol (MitoQ), are probably more effective than traditional dietary antioxidants (i.e., selenium, vitamin E) at alleviating oxidative stress, as they localize and accumulate within the mitochondria, potentiating their antioxidant activity. Thus, the present study aimed to investigate MitoQ's role during a thermal event in growing pigs. Herein, HS increased all body temperature indices, decreased feed intake (FI), and induced substantial body weight (BW) loss. Interestingly, the reduction in FI and BW was less dramatic in pigs receiving MitoQ. Changes in circulating metabolism and the acute phase response were observed due to the HS challenge; however, contrary to our expectations, these changes were not offset by MitoQ administration. Although our results suggest a positive MitoQ effect on growth performance, future studies are needed to corroborate the replicability of this response during HS.

Antiviral activity of flavonol against porcine epidemic diarrhea virus.

Porcine epidemic diarrhea virus (PEDV) remains one of the major causative microorganisms of viral diarrhea in piglets worldwide, with no approved drugs for treatment. We identified a natural molecule, flavonol, which is widely found in tea, vegetables and herbs. Subsequently, the antiviral activity of compound flavonol was evaluated in Vero cells and IPEC-J2 cells, and its anti-PEDV mechanism was analyzed by molecular docking and molecular dynamics. The results showed that flavonol could effectively inhibit viral progeny production, RNA synthesis and protein expression of PEDV strains in a dose-dependent manner. When flavonol was added simultaneously with viral infection in Vero cells, it demonstrated potent anti-PEDV activity by affecting the viral attachment and internalization phases. Similarly, in IPEC-J2 cells, flavonol effectively inhibited PEDV infection at different stages of infection, except for the release phase. Moreover, flavonol mainly interacts with PEDV Mpro through hydrogen bonds and hydrophobic forces, and the complex formed by it has high stability. Importantly, flavonol also showed broad-spectrum activity against other porcine enteric coronaviruses such as TGEV and PDCoV in vitro. These findings suggest that flavonol may exert antiviral effects by interacting with viral Mpro, thereby affecting viral replication. This means that flavonol is expected to become a potential drug to prevent or treat porcine enteric coronavirus.

Study of the therapeutic efficacy of DOKSI AVZ 500 in bacterial respiratory diseases in young pigs.

Background: Young farm animals are susceptible to opportunistic infections which may cause economic losses due to mortality and poor weight gain. The development of antimicrobial resistance and the desire to improve therapy efficacy and safety are the reasons to seek for new antibacterial drugs ensuring rapid recovery with minimum adverse events. Aim: To estimate the efficacy of DOKSI AVZ 500 in respiratory pathologies in young pigs. Methods: The study was conducted in 65-70-day-old Yorkshire piglets with signs of bacterial respiratory pathologies. The animals were treated with the test drug for 3 or 5 days. The reference group received TETRAMAX 500 which is similar to the test drug in terms of chemical structure, mechanism of action, and activity spectrum. The animal's status was assessed using clinical examination, clinical blood count, and bacteriological tests. Results: Both test and reference drugs were well tolerated and ensured the animal recovery within about 4 days. The recovery was accompanied by normalization of hematological parameters and flora composition. The bacterium associated with the disease development, Streptococcus suis, was virtually completely eliminated in all groups. No adverse events were noted. After the treatment, all the animals readily gained weight and live market quality. Conclusion: DOKSI AVZ 500 was a highly efficient therapy for respiratory pathologies caused by the resident opportunistic flora in piglets. It has also shown noninferiority vs. TETRAMAX 500 in terms of all the health-related parameters and thus can be recommended for introduction in veterinary practice in pig farms.

A novel function of benzoic acid to enhance intestinal barrier defense against PEDV infection in Piglets.

The intestinal barrier of newborn piglets is vulnerable and underdeveloped, making them susceptible to enteric virus infections. Benzoic acid (BA), employed as a growth promoter, exhibits the potential to enhance the gut health of piglets by modulating intestinal morphometry and tight junction dynamics. However, the extent to which BA regulates the intestinal mucus barrier through its impact on stem cells remains inadequately elucidated. Therefore, this study was conducted to investigate the effects of BA on the intestinal barrier and the differentiation of intestinal stem cells, employing in vivo piglet and in vitro intestinal organoid models. Our investigation revealed a significant increase in the number of goblet cells within the small intestine, as well as the strengthening of the mucus barrier in vivo following oral treatment with BA, providing partial protection against PEDV infection in piglets. Additionally, in vitro cultivation of enteroids with BA led to a notable increase in the number of MUC2+ GCs, indicating the promotion of GC differentiation by BA. Furthermore, transcriptome analysis revealed an upregulation of the number of GCs and the expression of cell vesicle transport-related genes during BA stimulation, accompanied by the downregulation of the Wnt and Notch signaling pathways. Mechanistically, MCT1 facilitated the transport of BA, subsequently activating the MAPK pathway to mediate GC differentiation. Overall, this study highlights a novel function for BA as a feed additive in enhancing the intestinal mucus barrier by promoting intestinal GC differentiation, and further prevents viral infection in piglets.

Lizhong decoction inhibits porcine epidemic diarrhea virus in vitro and in vivo.

ETHNOPHARMACOLOGICAL RELEVANCE: Lizhong decoction (LZD) is a frequently utilized traditional Chinese remedy for diarrhea. It is unknown how effective it is as an antiviral against PEDV infection. AIM OF THE STUDY: In vitro and in vivo PEDV infection models were used to evaluate the anti-PEDV potential of LZD extract. MATERIALS AND METHODS: LC-MS was used for qualitative analysis of LZD. The antiviral effect of LZD against PEDV using flow cytometry (FC), Quantitative real-time polymerase chain reaction (QPCR), immunofluorescence assay (IFA) analysis in Vero and IPEC-J2 cells. Additionally, we measured the survival rate, clinical symptoms, body weights, fecal scores, temperature, histological analysis, and viral load in a model of newborn piglets infected with PEDV in order to assess the antiviral impact of LZD in vivo. RESULTS: In total, 648 compounds were identified, including 144 Alkaloids, 128 Terpenoids, etc. LZD effectively suppressed PEDV replication in vitro. According to time of addition experiments, LZD mostly inhibited PEDV during the viral life cycle's replication stages. During PEDV infection, LZD can Significantly decrease the apoptotic rate of IPEC-J2 cells and Vero cells. In comparison to the model group, LZD was able to decrease the viral titers in the infected piglets' intestinal and visceral tissues, ameliorate their intestinal pathology, cause a significant increase in body weight growth and increase the piglet survival rate. CONCLUSION: Our findings indicate that the aqueous solution derived from LZD suppressed PEDV replication both in vitro and in vivo, indicating its potential as a candidate for pharmaceutical development.