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Porcine astrovirus 4 (PoAstV4) has been recently associated with respiratory disease in pigs. In order to understand the scope of PoAstV4 infections and to support the development of a vaccine to combat PoAstV4 disease in pigs, we designed and produced a recombinant PoAstV4 capsid spike protein for use as an antigen in serological assays and for potential future use as a vaccine antigen. Structural prediction of the full-length PoAstV4 capsid protein guided the design of the recombinant PoAstV4 capsid spike domain expression plasmid. The recombinant PoAstV4 capsid spike was expressed in Escherichia coli, purified by affinity and size-exclusion chromatography, and its crystal structure was determined at 1.85 Å resolution, enabling structural comparisons to other animal and human astrovirus capsid spike structures. The recombinant PoAstV4 capsid spike protein was also used as an antigen for the successful development of a serological assay to detect PoAstV4 antibodies, demonstrating that the recombinant PoAstV4 capsid spike retains antigenic epitopes found on the native PoAstV4 capsid. These studies lay a foundation for seroprevalence studies and the development of a PoAstV4 vaccine for swine.

Background: African swine fever (ASF) is one of the deadliest swine diseases with haemorrhagic symptoms and a high mortality rate. Plant‐derived additives are potential antiviral agents against viruses due to their environmental and user‐friendly properties. Objectives: This study aims to evaluate the efficacy of plant‐based additives (Phyto.A04 and Phyto.B) compared to an organic acid blend (OAB) in inactivating ASF virus (ASFV) in cell culture and feed. Methods: ASFV‐spiked feed was treated with individual or combined additives such as OAB, Phyto.A04 and Phyto.B. The viability of ASFV after treatment of ASFV‐spiked feed with additives was then confirmed by both methods, real‐time PCR and cell culture. Results: The results of the in vitro test with cell cultures showed that all three additives (OAB, Phyto.A04 and Phyto.B) exerted a strong virucidal effect on ASFV in porcine alveolar macrophage cells. OAB at a concentration of 0.3% reduced the virus concentration from 4.48 log10 HAD50/mL after 1 day of treatment (day 1) to 3.29 log10 HAD50/mL after 3 days of treatment (day 3) and remained undetected after 7 days of treatment (day 7). In Phyto.A04 with 1%, the virus was only detectable on day 1 (3.53 log10 HAD50/mL). Phyto.B with 0.01% and 0.05% both showed good efficacy in completely inhibiting virus presence on days 3 and 7. Conclusions: All additives, OAB, Phyto.A04 and Phyto.B, were able to inactivate ASFV in a dose‐dependent manner, as confirmed by cell culture and PCR methods. The combination of additives at different concentrations consistently improved the virucidal results. [ABSTRACT FROM AUTHOR]

Simple Summary: Spatial epidemiology, integrating traditional epidemiology, geography, statistics, environmental science, and ecology, provides a comprehensive framework for analyzing the spatial dimensions of health and disease. This interdisciplinary approach enhances the development of effective public health strategies and interventions. However, its multifaceted nature can bring complexities in practical application. Using the case of spatial epidemiology in swine viral diseases (SVDs), we illustrate the objectives, methodologies, and essential considerations for the application of spatial epidemiology, which we hope to offer as a comprehensive reference for researchers in this field. Spatial epidemiology offers a comprehensive framework for analyzing the spatial distribution and transmission of diseases, leveraging advanced technical tools and software, including Geographic Information Systems (GISs), remote sensing technology, statistical and mathematical software, and spatial analysis tools. Despite its increasing application to swine viral diseases (SVDs), certain challenges arise from its interdisciplinary nature. To support novices, frontline veterinarians, and public health policymakers in navigating its complexities, we provide a comprehensive overview of the common applications of spatial epidemiology in SVD. These applications are classified into four categories based on their objectives: visualizing and elucidating spatiotemporal distribution patterns, identifying risk factors, risk mapping, and tracing the spatiotemporal evolution of pathogens. We further elucidate the technical methods, software, and considerations necessary to accomplish these objectives. Additionally, we address critical issues such as the ecological fallacy and hypothesis generation in geographic correlation analysis. Finally, we explore the future prospects of spatial epidemiology in SVD within the One Health framework, offering a valuable reference for researchers engaged in the spatial analysis of SVD and other epidemics. [ABSTRACT FROM AUTHOR]

The objective of the study was to identify risk factors for reintroduction of Actinobacillus pleuopneumoniae and Mycoplasma hyopneumoniae (enzootic pneumonia) onto pig farms in areas in Switzerland that were involved in an eradication programme from 1996 to 1999 and to assess the role of dealers in relation to these reinfections. The study was based on the comparison of pig farms that were reinfected in the year 2000 (cases) and pig farms that remained uninfected in the same area (controls). Additionally, data were collected from Swiss pig dealers and transport companies. Out of a total of 3983 farms, 107 farms were reinfected in the year 2000. The incidences were 0.1% for Actinobacillus pleuopneumoniae and 2.6% for Mycoplasma hyopneumoniae (enzootic pneumonia). Compared to reinfection rates prior to the eradication programme, this is a considerable reduction. Statistically significant risk factors for the reinfection were 'finishing farm', 'large mixed breeding-finishing farm', 'reinfected neighbour' and 'parking site for pig transport vehicles close to the farm'. Pig farmers that purchased pigs from only one supplier per batch had a lower risk of reintroducing infection (protective factor). As long as infected and uninfected regions co-exist in Switzerland, direct and indirect contact between farms, pig herds and slaughter sites via transport vehicles are a major pathway of disease spread. Risk management measures linked to these contacts are therefore of key importance. The survey of dealers indicated various areas for improvement such as strategic planning of pick-up routes or cleaning and disinfecting of trucks. [ABSTRACT FROM AUTHOR]

Streptococcus suis is a major swine pathogen and zoonotic agent, causing important economic losses to the porcine industry. Here, we used genomics approaches to characterize 251 S. suis isolates recovered from diseased pigs across Belgium, France, Germany, Hungary, the Netherlands, Spain, and the United Kingdom. We identified 13 serotypes, being serotypes 9 and 2 the most prevalent, and 34 sequence types (STs), including 16 novel STs, although ST16 and ST1 dominated the strain population. Phylogenetic analysis revealed complex genetic relationships, notable geographic clustering, and potential differential capacity for capsular switching among serotype 9 isolates. We found antimicrobial resistance (AMR) genes in 85.3% of the isolates, with high frequencies of genes conferring resistance to tetracyclines and macrolides. Specifically, 49.4% of the isolates harbored the tetO gene, and 64.9% possessed the ermB gene. Additionally, we observed a diverse array of virulence-associated genes (VAGs), including the classical VAGs mrp, epf, and sly, with variable presence across different genotypes. The high genetic diversity among European S. suis isolates highlights the importance of targeted antimicrobial use and flexible vaccine strategies. Rapid strain characterization is crucial for optimizing swine health management, enabling tailored interventions like the development of autovaccines to mitigate S. suis infections. [ABSTRACT FROM AUTHOR]

African swine fever (ASF) is a highly contagious and lethal disease of swine caused by African swine fever virus (ASFV), and the mortality rate caused by virulent stains can approach 100%. Many ASFV viral proteins suppress the interferon production to evade the host's innate immune responses. However, whether ASFV MGF360-4L could inhibit type I interferon (IFN-I) signaling pathway and the underlying molecular mechanisms remain unknown. Our study, indicated that ASFV MGF360-4L could negatively regulates the cGAS-STING mediated IFN-I signaling pathway. Overexpressing ASFV MGF360-4L could inhibit the cGAS/STING signaling pathway by inhibiting the interferon-b promoter activity, which was induced by cGAS/STING, TBK1, and IRF3-5D, and further reduced the transcriptional levels of ISG15, ISG54, ISG56, STAT1, STAT2, and TYK2. Confocal microscopy and immunoprecipitation revealed that MGF360-4L colocalized and interacted with IRF3, and WB revealed that ASFV MGF360-4L suppressed the phosphorylation of IRF3. 4L-F2 (75-162 aa) and 4L-F3 (146-387 aa) were the crucial immunosuppressive domains and sites. Altogether, our study reveals ASFV MGF360-4L inhibited cGAS-STING mediated IFN-I signaling pathways, which provides insights into an evasion strategy of ASFV involving in host's innate immune responses. [ABSTRACT FROM AUTHOR]

Simple Summary: Wildlife in human-dominated landscapes often faces a range of disturbances that can alter their natural behaviors. Wild boar (Sus scrofa) populations are increasing across Europe, raising concerns about ecological impacts and the spread of diseases such as African swine fever (ASF). This research focuses on the behavioral adaptations of wild boars in response to specific human disturbances. Utilizing advanced biologging technologies, specifically accelerometer and magnetometer combined with dead reckoning methods, fifteen wild boars in a suburban forest near Prague were monitored over a period from February 2020 to July 2021. This study provides insights into the wild boar's resilience, revealing that while the animals are inclined to flee when near disturbances, they predominantly remain in a resting state otherwise. Their most common reaction was to continue resting. These observations underscore the potential role of disturbance management in controlling the spread of zoonotic diseases such as African swine fever (ASF) within wild boar populations. Currently, African swine fever (ASF), a highly fatal disease has become pervasive, with outbreaks recorded across European countries, leading to preventative measures to restrict wild boar (Sus scrofa L.) movement, and, therefore, keep ASF from spreading. This study aims to detail how specific human activities—defined as "car", "dog", "chainsaw", and "tourism"—affect wild boar behavior, considering the disturbance proximity, and evaluate possible implications for wild boar management in ASF-affected areas. Wild boar behavior was studied using advanced biologging technology. This study tracks and analyzes wild boar movements and behavioral responses to human disturbances. This study utilizes the dead reckoning method to precisely reconstruct the animal movements and evaluate behavioral changes based on proximity to disturbances. The sound of specific human activities was reproduced for telemetered animals from forest roads from different distances. Statistical analyses show that wild boars exhibit increased vigilance and altered movement patterns in response to closer human activity, but only in a small number of cases and with no significantly longer time scale. The relative representation of behaviors after disruption confirmed a high instance of resting behavior (83%). Running was the least observed reaction in only 0.9% of all cases. The remaining reactions were identified as foraging (5.1%), walking (5.0%), standing (2.2%), and other (3.8%). The findings suggest that while human presence and activities do influence wild boar behavior, adherence to movement restrictions and careful management of human activity in ASF-infected areas is not a necessary measure if human movement is limited to forest roads. [ABSTRACT FROM AUTHOR]

African swine fever (ASF) is one of the deadliest swine diseases, causing significant economic losses, threatening food security, and limiting pig production in affected countries. In the absence of an effective ASF vaccine, prevention and control of ASF depend mainly on effective biosecurity measures. In this study, the efficacy of SAFER®, a powdered disinfectant containing clay, an acid complex, and the active ingredient thyme essential oil, was tested against the ASF virus. The results showed that ASFV isolate (VNUA/HY/ASF1/Vietnam/2019) was inactivated by 3.5 and 5 Log10HAD50/ml after 20 and 120  min of treatment with SAFER®, respectively. When body fluids contaminated with ASFV, such as blood, saliva, urine, and feces, were treated with SAFER® for 20  min, the ASFV titer was reduced by 1.6, 2.2, 2.0, and 2.2 Log10HAD50/ml, respectively. [ABSTRACT FROM AUTHOR]

The African swine fever virus (ASFV) is a large and complex DNA virus that causes a highly lethal disease in swine, for which no antiviral drugs or vaccines are currently available. Studying viral–host protein–protein interactions advances our understanding of the molecular mechanisms underlying viral replication and pathogenesis and can facilitate the discovery of antiviral therapeutics. In this study, we employed affinity tagging and purification mass spectrometry to characterize the interactome of VPS39, an important cellular factor during the early phase of ASFV replication. The interaction network of VPS39 revealed associations with mitochondrial proteins involved in membrane contact sites formation and cellular respiration. We show that the ASFV proteins CP204L and A137R target VPS39 by interacting with its clathrin heavy-chain functional domain. Furthermore, we elaborate on the potential mechanisms by which VPS39 may contribute to ASFV replication and prioritize interactions for further investigation into mitochondrial protein function in the context of ASFV infection. [ABSTRACT FROM AUTHOR]

A priority to facilitate the application of lipofection to generate genetically modified porcine embryos and animals will be the use of zona pellucida (ZP)-intact oocytes and zygotes. Recently, our group produced genetically modified embryos by lipofection of ZP-intact oocytes during in vitro fertilization (IVF). This study investigates the effect of two commercial lipofection reagents, Lipofectamine 3000 and Lipofectamine CRISPRMAX, on embryo development and mutation efficiency in ZP-intact porcine oocytes. We compared these reagents with the electroporation method and a control group using two sgRNAs targeting the CAPN3 and CD163 genes. The detrimental effects on cleavage rates were observed in both lipofection treatments compared to the control and electroporated groups. However, blastocyst rates were higher in the Lipofectamine 3000 group than in the electroporated group for both genes. Mutation parameters varied by target gene, with Lipofectamine 3000 achieving higher mutation rates for CD163, while all groups were similar for the CAPN3 gene. Overall efficiency was similar for both lipofectamines, confirming their feasibility for use. In addition, we evaluated the effect of coincubation time (4, 8, and 24 h) on IVF outcomes, embryo development, and mutation parameters. Results indicated that an 8-h coincubation period optimized fertilization and mutation efficiency without significant toxic effects. This study demonstrates that lipofection with either Lipofectamine 3000 or CRISPRMAX during IVF is an effective method for generating genetically modified porcine embryos without the need for specialized equipment or trained personnel, with efficiencies similar to or greater than electroporation. This study also highlights the importance of optimizing reagent selection and coincubation times. There is no difference between Lipofectamine 3000 and CRISPRMAXTM in terms of embryo development and mutation efficiency, and under our experimental conditions, the optimal coincubation time with lipofectamine is 8 h. • Lipofection during IVF is an effective method to generate mutant porcine embryos. • Lipofectamine 3000 and CRISPRMAX are similar in efficiency. • Lipofection maintains high blastocyst rates. • Optimal coincubation time with Lipofectamine is 8 h. [ABSTRACT FROM AUTHOR]

ABSTRACT The objective of this study was to assess the impact of the vehicle of administration and the prandial state of post weaning piglets on the indices of therapeutic efficacy for different broad‐spectrum antibiotic/pathogen combinations. Pharmacokinetic data were retrieved from previous studies, in which we orally administered oxytetracycline (OTC), fosfomycin (FOS), or amoxicillin (AMX) according to the following treatments: dissolved in soft water to fasted or non‐fasted piglets, dissolved in hard water to fasted or non‐fasted piglets, and mixed with feed. Minimum inhibitory concentration (MIC) values for susceptible strains of bacteria causing swine diseases were obtained from the database of European Committee on Antimicrobial Susceptibility Testing (EUCAST) for each antibiotic. Pharmacokinetic/pharmacodynamic (PK/PD) indices of therapeutic efficacy—drug exposure over the dosing interval (fAUC/MIC) for OTC and FOS; time that free drug concentration remains above MIC (%fT>MIC) for AMX—were calculated for each antibiotic/pathogen combination under each treatment. After all OTC and in‐feed FOS and AMX treatments, the indices of therapeutic efficacy were below the target value for all the study microorganisms. When FOS or AMX were delivered dissolved in soft or hard water, the indices were above the target value over which therapeutic efficacy would be expected for Escherichia coli treated with FOS and, Glaesserella parasuis, Pasteurella multocida, and Actinobacillus pleuropneumoniae treated with AMX. The prandial state of piglets showed no influence on the indices of therapeutic efficacy. Pharmacokinetic profiles of broad‐spectrum antibiotics, specifically the ability to achieve target concentrations, may be largely reduced due to drug interactions with components present in feed or water resulting in a discrepancy with PK/PD principles of prudent and responsible use of antibiotics. [ABSTRACT FROM AUTHOR]

African swine fever (ASF) is a highly contagious and severe hemorrhagic transboundary swine viral disease with up to a 100% mortality rate, which leads to a tremendous socio-economic loss worldwide. The lack of safe and efficacious ASF vaccines is the greatest challenge in the prevention and control of ASF. In this study, we generated a safe and effective live-attenuated virus (LAV) vaccine candidate VNUA-ASFV-LAVL3 by serially passaging a virulent genotype II strain (VNUA-ASFV-L2) in an immortalized porcine alveolar macrophage cell line (3D4/21, 50 passages). VNUA-ASFV-LAVL3 lost its hemadsorption ability but maintained comparable growth kinetics in 3D4/21 cells to that of the parental strain. Notably, it exhibited significant attenuation of virulence in pigs across different doses (103, 104, and 105 TCID50). All vaccinated pigs remained healthy with no clinical signs of African swine fever virus (ASFV) infection throughout the 28-day observation period of immunization. VNUA-ASFV-LAVL3 was efficiently cleared from the blood at 14–17 days post-infection, even at the highest dose (105 TCID50). Importantly, the attenuation observed in vivo did not compromise the ability of VNUA-ASFV-LAVL3 to induce protective immunity. Vaccination with VNUA-ASFV-LAVL3 elicited robust humoral and cellular immune responses in pigs, achieving 100% protection against a lethal wild-type ASFV (genotype II) challenge at all tested doses (103, 104, and 105 TCID50). Furthermore, a single vaccination (104 TCID50) provided protection for up to 2 months. These findings suggest that VNUA-ASFV-LAVL3 can be utilized as a promising safe and efficacious LAV candidate against the contemporary pandemic genotype II ASFV. [ABSTRACT FROM AUTHOR]

African swine fever virus (ASFV) is the causative agent of African swine fever (ASF), a highly infectious and lethal disease of domesticated swine. Outbreaks of ASF have been mostly restricted to the continent of Africa. The outbreaks that have occurred outside of Africa were controlled by extensive depopulation of the domesticated pig population. However, in 2007, an outbreak occurred in the country of Georgia, where ASFV infected wild pigs and quickly spread across eastern Europe. Since the reintroduction of ASF into Europe, variants of the current pandemic strain, ASFV Georgia 2007/01 (ASFV-G), which is classified as Genotype 2 based on p72 sequencing, have been reported in countries within western Europe, Asia, and the island of Hispaniola. Additionally, isolates collected in 2020 confirmed the presence of variants of ASFV-G in Nigeria. Recently, we reported similar variants of ASFV-G collected from domestic pigs suspected of dying of ASF in Ghana in 2022. Here, we retroactively report, based on full-length sequencing, that similar variants were present in Ghana in 2021. The SNP analysis revealed derivatives of ASFV with distinct genetic markers. Furthermore, we identified three full-length ASFV genomes as Genotype 1, indicating that there were two genotypes circulating in proximity during the 2021 ASF outbreaks in Ghana. [ABSTRACT FROM AUTHOR]

Pseudorabies virus (PRV) is one of the herpes viruses that can infect a wide range of animals including pigs, cattle, sheep, mice, and wild animals. PRV is a neurotropic alphaherpesvirus capable of infecting a variety of mammals. There is a rising interest in the targeted application of probiotic bacteria to prevent viral diseases, including PRV. In this study, the surface expression of enhanced green fluorescent protein (EGFP) on recombinant Lactiplantibacillus plantarum NC8 (rNC8) through the LP3065 LPxTG motif of Lactobacillus plantarum WCFS1 was generated. The surface expression was observed through confocal microscopy. Dendritic cell targeting peptides (DCpep) were also fused with LPxTG that help to bind with mouse DCs. The PRV-gD was cloned in LP3065 LPxTG, resulting in the generation of rNC8-LP3065-gD. Inactivated rNC8-LP3065-gD was administered intravenously in mice on days 1 and 7 at a dose of 200 µL (109 CFU/mouse) for monitoring immunogenicity. Subsequently, a challenge dose of PRV TJ (104 TCID50) was administered intramuscularly at 14 days post-immunization. The survival rate of the immunized mice reached 80% (4/5) with no significant signs of illness. A significant rise in anti-gD antibodies was detected in the immunized mice by ELISA. Quantitative PCR (qPCR) results showed decreased viral loading in different body tissues. Flow cytometry of lymphocytes derived from mice spleen indicated an increase in CD3+CD4+ T cells, but CD3+CD8+ T cells were not detected. Moreover, it offers a model to delineate immune correlates with rNC8-induced immunity against swine viral diseases. [ABSTRACT FROM AUTHOR]

Simple Summary: Porcine pleuropneumonia, caused by Actinobacillus pleuropneumoniae, is one of the main causes of massive losses in the pig industry, with a high economic impact. This study aimed to identify A. pleuropneumoniae serotypes isolated from pneumonic lesions in dead pigs, naturally infected, in some Piedmontese farms and to describe the macroscopic and microscopic lesions. The identification of circulating serotypes in swine farming is crucial to adopting optimal strategies to control the diseases, such as vaccination plans and biosecurity measures. Porcine pleuropneumonia (PPP) is one of the main causes leading to massive losses in the pig industry, with high economic impacts. Among different etiological agents, Actinobacillus pleuropneumoniae (APP) is responsible for severe fibrinous-necrotizing pleuropneumonia. A total of 19 different APP serotypes are currently recognized. This study aimed to identify APP serotypes isolated from pneumonic lesions in naturally infected and dead pigs in the Piedmont Region and to describe lesions. A total of 107 dead pigs with a suspected PPP diagnosis were included in this study. Lungs were evaluated using gross-pathology scoring systems, histopathology, and APP isolation and serotypes identification by multiplex PCR were conducted. Gross lung lesions were mainly represented by fibrinous pneumonia and pleuropneumonia. APP was isolated in 20/107 (18.7%) samples. PCR indicated APP DNA presence in 53/107 (49.5%) of lung samples. The most observed serotypes were serotype 2 in 24/53 (45.3%) and serotype 6 in 13/53 (24.5%) samples. Moreover, multiplex PCR results suggested a coinfection of different serotypes in five samples. This study emphasizes the importance of an integrated approach, utilizing various techniques, such as gross- and histopathology, and bacteriological culture and PCR, to enhance the diagnosis of APP infections. [ABSTRACT FROM AUTHOR]

Porcine circovirus type 3 (PCV3) is closely associated with various diseases, such as the porcine dermatitis, nephropathy syndrome, and multisystemic clinicopathological diseases. PCV3-associated diseases are increasingly recognized as severe diseases in the global swine industry. Ring finger protein 2 (RNF2), an E3 ubiquitin ligase exclusively located in the nucleus, contributes to various biological processes. This ligase interacts with the PCV3 Cap. However, its role in PCV3 replication remains unclear. This study confirmed that the nuclear localization signal domain of the Cap and the RNF2 N-terminal RING domain facilitate the interaction between the Cap and RNF2. Furthermore, RNF2 promoted the binding of K48-linked polyubiquitination chains to lysine at positions 139 and 140 (K139 and K140) of the PCV3 Cap, thereby degrading the Cap. RNF2 knockdown and overexpression increased or decreased PCV3 replication, respectively. Moreover, the RING domain-deleted RNF2 mutant eliminated the RNF2- induced degradation of the PCV3 Cap and RNF2-mediated inhibition of viral replication. This indicates that both processes were associated with its E3 ligase activity. Our findings demonstrate that RNF2 can interact with and degrade the PCV3 Cap via its N-terminal RING domain in a ubiquitination-dependent manner, thereby inhibiting PCV3 replication. IMPORTANCE Porcine circovirus type 3 is a recently described pathogen that is prevalent worldwide, causing substantial economic losses to the swine industry. However, the mechanisms through which host proteins regulate its replication remain unclear. Here, we demonstrate that ring finger protein 2 inhibits porcine circovirus type 3 replication by interacting with and degrading the Cap of this pathogen in a ubiquitination-dependent manner, requiring its N-terminal RING domain. Ring finger protein 2-mediated degradation of the Cap relies on its E3 ligase activity and the simultaneous existence of K139 and K140 within the Cap. These findings reveal the mechanism by which this protein interacts with and degrades the Cap to inhibit porcine circovirus type 3 replication. This consequently provides novel insights into porcine circovirus type 3 pathogenesis and facilitates the development of preventative measures against this pathogen. [ABSTRACT FROM AUTHOR]

The swine acute diarrhea syndrome coronavirus (SADS-CoV) has caused significant disruptions in porcine breeding and raised concerns about potential human infection. The nucleocapsid (N) protein of SADS-CoV plays a vital role in viral assembly and replication, but its structure and functions remain poorly understood. This study utilized biochemistry, X-ray crystallography, and immunization techniques to investigate the N protein’s structure and function in SADS-CoV. Our findings revealed distinct domains within the N protein, including an RNA-binding domain, two disordered domains, and a dimerization domain. Through biochemical assays, we confirmed that the N-terminal domain functions as an RNA-binding domain, and the C-terminal domain is involved in dimerization, with the crystal structure analysis providing visual evidence of dimer formation. Immunization experiments demonstrated that the disordered domain 2 elicited a significant antibody response. These identified domains and their interactions are crucial for viral assembly. This comprehensive understanding of the N protein in SADS-CoV enhances our knowledge of its assembly and replication mechanisms, enabling the development of targeted interventions and therapeutic strategies. IMPORTANCE SADS-CoV is a porcine coronavirus that originated from a bat HKU2-related coronavirus. It causes devastating swine diseases and poses a high risk of spillover to humans. The coronavirus N protein, as the most abundant viral protein in infected cells, likely plays a key role in viral assembly and replication. However, the structure and function of this protein remain unclear. Therefore, this study employed a combination of biochemistry and X-ray crystallography to uncover distinct structural domains in the N protein, including RNA-binding domains, two disordered domains, and dimerization domains. Additionally, we made the novel discovery that the disordered domain elicited a significant antibody response. These findings provide new insights into the structure and functions of the SADS-CoV N protein, which have important implications for future studies on SADS-CoV diagnosis, as well as the development of vaccines and anti-viral drugs. [ABSTRACT FROM AUTHOR]

The outbreak of infectious diseases in swine, such as classical swine fever (CSF), has become a significant concern in the pig‐farming industry. In Japan, after the re‐emergence of CSF in 2018, farms are now exposed to the risk of transmission from infected wild boar and CSF‐contaminated farms. This study aimed to identify biosecurity measures that were effective for the prevention of CSF introduction into farms during the period from the beginning of the CSF epidemic to the implementation of a vaccination campaign for domestic pigs at risk. The probability of virus introduction was assumed to be increased by the elevated risk from CSF‐infected wild boar and infected farms around the farm. The risk from infected wild boar was represented by the prevalence of CSF in wild boar or the occupancy of 1‐km grid cells with infected wild boar within 10‐km radii from a pig farm and the occurrence of CSF outbreaks on neighboring farms. Conversely, the probability of virus introduction was assumed to decrease in response to on‐farm biosecurity measures being implemented on each farm. The implementation of biosecurity measures on the farms and farm attributes were obtained through a questionnaire survey. Analyses were performed on each farm under the weekly situations where infected wild boar were both absent and present in the vicinity using a binomial generalized linear model. On farms where infected wild boar were not present around farms, daily washing and disinfecting of work clothing in pig houses was identified as the main measure to reduce the risk of CSF introduction into farms. On farms with infected wild boar in the vicinity, the absence of public roads on the farm and preventing wildlife intrusion into the areas where pig carcasses were stored were demonstrated to be effective in preventing CSF introduction. Based on the assumption that strict and comprehensive biosecurity measures are required to prevent CSF introduction, the implementation of these potentially effective measures is worth being prioritized. [ABSTRACT FROM AUTHOR]

• This study presents a novel combined vaccines candidate against FMD and SVA, and provides new insights for the development of combination vaccines for other viral swine diseases. Here we report, to our knowledge, the first development of a VLPs-based combined vaccines targeting FMDV type A and O, and SVA strains. • Inactivated vaccines are unable to serologically differentiate infected from vaccinated animals, thus hindering pathogen eradication. Beneficially, virus-like particles (VLPs)-based vaccines resemble natural viruses in size and antigen structure, offering an alternative tool to circumvent these limitations. • We formulated a combined vaccines consisting of three distinct VLPs specifically designed to target SVA as well as FMDV serotypes O and A. The immunocompatibility and immunological efficacy of this multi-target vaccines were rigorously assessed by optimizing various formulation parameters, immune indicators, and safety metrics. • Pig immunization studies revealed that the combined VLPs vaccines elicited antigen-specific and high serum antibody responses comparable to those elicited by its corresponding individual vaccines. Additionally, the combined VLPs vaccines immune serums strongly neutralized FMDV type A and O, and SVA strains with neutralization titers similar to those of their individual counterparts, suggesting a good compatibility among the three VLPs components regarding their immunogenicity. • Importantly, sera from pigs immunized with the combined VLPs vaccines conferred efficient protection against single or mixed infections with FMDV type A and O, and SVA viruses. In contrast, the individual vaccines could only protect pigs against homologous virus infections and were not effective against heterologous challenges. Inactivated vaccines lack the capability to serologically differentiate between infected and vaccinated animals, thereby impeding the effective eradication of pathogen. Conversely, vaccines based on virus-like particles (VLPs) emulate natural viruses in both size and antigenic structure, presenting a promising alternative to overcome these limitations. As the complexity of swine infectious diseases increases, the increase of vaccine types and doses may intensify the stress response. This exacerbation can lead to diminished productivity, failure of immunization, and elevated costs. Given the critical dynamics of co-infection and the clinically indistinguishable symptoms associated with foot-and-mouth disease virus (FMDV) and senecavirus A (SVA), there is a dire need for an efficacious intervention. To address these challenges, we developed a combined vaccine composed of three distinct VLPs, specifically designed to target SVA and FMDV serotypes O and A. Our research demonstrates that this trivalent VLP vaccine induces antigen-specific and robust serum antibody responses, comparable to those produced by the respective monovalent vaccines. Moreover, the immune sera from the combined VLP vaccine strongly neutralized FMDV type A and O, and SVA, with neutralization titers comparable to those of the individual vaccines, indicating a high level of immunogenic compatibility among the three VLP components. Importantly, the combined VLPs vaccines-immunized sera conferred efficient protection against single or mixed infections with FMDV type A and O, and SVA viruses in pigs. In contrast, individual vaccines could only protect pigs against homologous virus infections and not against heterologous challenges. This study presents a novel combined vaccines candidate against FMD and SVA, and provides new insights for the development of combination vaccines for other viral swine diseases. [ABSTRACT FROM AUTHOR]

African Swine Fever (ASF) is a reportable disease of swine that causes farreaching losses to affected countries and regions. Early detection is critically important to contain and mitigate the impact of ASF outbreaks, for which timely available data is essential. This research examines the potential use of Google Trends data as an early indicator of ASF outbreaks in Southeast Asia, focusing on the three largest swine producing countries, namely, Vietnam, the Philippines, and Thailand. Cross-correlation and Kullback-Leibler (KL) divergence indicators were used to evaluate the association between Google search trends and the number of ASF outbreaks reported. Our analysis indicate strong and moderate correlations between Google search trends and number of ASF outbreaks reported in Vietnam and the Philippines, respectively. In contrast, Thailand, the country of this group in which outbreaks were reported last, exhibits the weakest correlation (KL = 2.64), highlighting variations in public awareness and disease dynamics. These findings suggest that Google search trends are valuable for early detection of ASF. As the disease becomes endemic, integrating trends with other epidemiological data may support the design and implementation of surveillance strategies for transboundary animal diseases in Southeast Asia. [ABSTRACT FROM AUTHOR]

This study aims to explore the current application status and development prospects of Chinese herbal medicine in preventing and treating swine viral infectious diseases over the past five years. By adopting the method of literature review, we collect, organize, and analyze relevant research literature, with the goal of summarizing and summarizing the research progress in this field. Through research, we found that swine infectious diseases have caused serious economic losses in the breeding industry and that some diseases cannot be fully protected by using vaccines. Therefore, we need new means to prevent diseases. The use of Chinese herbal medicine for the prevention and treatment of related diseases has become a reliable means. This study first briefly introduces the common infectious diseases of pigs and the risks and challenges faced by prevention and treatment, then reads the literature comparing the treatment with Western medicine and traditional Chinese medicine, proving the reliability of traditional Chinese medicine treatment and the unique advantages of Chinese herbal medicine. Afterwards, we summarized the literature on the prevention and treatment of related swine diseases with Chinese herbal medicine in the past five years, and finally made a summary and outlook, hoping to provide ideas for relevant researchers and workers. [ABSTRACT FROM AUTHOR]

The African swine fever virus (ASFV) is an often deadly disease in swine and poses a threat to swine livestock and swine producers. With its complex genome containing more than 150 coding regions, developing effective vaccines for this virus remains a challenge due to a lack of basic knowledge about viral protein function and protein–protein interactions between viral proteins and between viral and host proteins. In this work, we identified ASFV-ASFV protein–protein interactions (PPIs) using artificial intelligence-powered protein structure prediction tools. We benchmarked our PPI identification workflow on the Vaccinia virus, a widely studied nucleocytoplasmic large DNA virus, and found that it could identify gold-standard PPIs that have been validated in vitro in a genome-wide computational screening. We applied this workflow to more than 18,000 pairwise combinations of ASFV proteins and were able to identify seventeen novel PPIs, many of which have corroborating experimental or bioinformatic evidence for their protein–protein interactions, further validating their relevance. Two protein–protein interactions, I267L and I8L, I267L__I8L, and B175L and DP79L, B175L__DP79L, are novel PPIs involving viral proteins known to modulate host immune response. [ABSTRACT FROM AUTHOR]

One of the most significant diseases in the swine business, porcine reproductive and respiratory syndrome virus (PRRSV) causes respiratory problems in piglets and reproductive failure in sows. The PRRSV nucleocapsid (N) protein is essential for the virus' assembly, replication, and immune evasion. Stages in the viral replication cycle can be impacted by interactions between the PRRSV nucleocapsid protein and the host protein components. Therefore, it is of great significance to explore the interaction between the PRRSV nucleocapsid protein and the host. Nevertheless, no information has been published on the network of interactions between the nucleocapsid protein and the host proteins in primary porcine alveolar macrophages (PAMs). In this study, 349 host proteins interacting with nucleocapsid protein were screened in the PRRSV-infected PAMs through a liquid chromatography–tandem mass spectrometry (LC–MS/MS)-based proteomics approach. Bioinformatics analysis, which included gene ontology annotation, Kyoto Encyclopedia of Genes and Genomes database enrichment, and a protein–protein interaction (PPI) network, revealed that the host proteins interacting with PRRSV-N may be involved in protein binding, DNA transcription, metabolism, and innate immune responses. This study confirmed the interaction between the nucleocapsid protein and the natural immune-related proteins. Ultimately, our findings suggest that the nucleocapsid protein plays a pivotal role in facilitating immune evasion during a PRRSV infection. This study contributes to enhancing our understanding of the role played by the nucleocapsid protein in viral pathogenesis and virus–host interaction, thereby offering novel insights for the prevention and control of PRRS as well as the development of vaccines. [ABSTRACT FROM AUTHOR]

Shiga toxin-producing Escherichia coli (STEC) poses a significant public health risk due to its zoonotic potential and association with severe human diseases, such as hemorrhagic colitis and hemolytic uremic syndrome. Ruminants are recognized as primary reservoirs for STEC, but swine also contribute to the epidemiology of this pathogen, highlighting the need for effective prevention strategies across species. Notably, a subgroup of STEC that produces Shiga toxin type 2e (Stx2e) causes edema disease (ED) in newborn piglets, economically affecting pig production. This study evaluates the immunogenicity of a chimeric protein-based vaccine candidate against STEC in pregnant sows and the subsequent transfer of immunity to their offspring. This vaccine candidate, which includes chimeric proteins displaying selected epitopes from the proteins Cah, OmpT, and Hes, was previously proven to be immunogenic in pregnant cows. Our analysis revealed a broad diversity of STEC serotypes within swine populations, with the cah and ompT genes being prevalent, validating them as suitable antigens for vaccine development. Although the hes gene was detected less frequently, the presence of at least one of these three genes in a significant proportion of STEC suggests the potential of this vaccine to target a wide range of strains. The vaccination of pregnant sows led to an increase in specific IgG and IgA antibodies against the chimeric proteins, indicating successful immunization. Additionally, our results demonstrated the effective passive transfer of maternal antibodies to piglets, providing them with immediate, albeit temporary, humoral immunity against STEC. These humoral responses demonstrate the immunogenicity of the vaccine candidate and are preliminary indicators of its potential efficacy. However, further research is needed to conclusively evaluate its impact on STEC colonization and shedding. This study highlights the potential of maternal vaccination to protect piglets from ED and contributes to the development of vaccination strategies to reduce the prevalence of STEC in various animal reservoirs. [ABSTRACT FROM AUTHOR]

Swine are increasingly studied as animal models of human disease. The anatomy, size, longevity, physiology, immune system, and metabolism of swine are more like humans than traditional rodent models. In addition, the size of swine is preferred for surgical placement and testing of medical devices destined for humans. These features make swine useful for biomedical, pharmacological, and toxicological research. With recent advances in gene-editing technologies, genetic modifications can readily and efficiently be made in swine to study genetic disorders. In addition, gene-edited swine tissues are necessary for studies testing and validating xenotransplantation into humans to meet the critical shortfall of viable organs versus need. Underlying all of these biomedical applications, the knowledge of husbandry, background diseases and lesions, and biosecurity needs are important for productive, efficient, and reproducible research when using swine as a human disease model for basic research, preclinical testing, and translational studies. [ABSTRACT FROM AUTHOR]

Simple Summary: Diseases in the swine industry can cause major economic and health issues. This review examines R0 estimates, which measure how efficiently respiratory diseases spread among pigs and compares transmission risks within and between farms. Seven diseases were studied: Aujeszky's disease, PPRSV, Circovirus, Influenza A, Encephalomyocarditis Virus, Classical Swine Fever, and African Swine Fever. Data from research articles showed varying R0 values, with higher transmission rates within herds for some diseases. Effective disease control requires prompt detection, response to outbreaks, and continuous monitoring to reduce its impact on the swine industry. Diseases in the swine industry can cause significant economic and health impacts. This review examines R0 estimates for respiratory diseases in pigs, assessing variations and comparing transmission risks within and between farms. A literature search of three databases aggregated peer-reviewed research articles on swine viral respiratory diseases' R0 values. The study focused on seven diseases: Aujeszky's disease (AD), Porcine Reproductive and Respiratory Syndrome Virus (PRRSV), Circovirus, Influenza A (IA), Encephalomyocarditis Virus (EV), Classical Swine Fever (CSF), and African Swine Fever (ASF). R0 values were estimated for transmission within and between herds/farms using various methods, from complex mathematical models to simple calculations. Data primarily came from disease surveillance and laboratory experiments. The median R0 for within-herd and between-herd transmission was 10 and 3.31 for AD, 2.78 and 1.14 for PRRSV, 5.9 and 0.89 for Circovirus, 1.75 and 1.6 for CSF, and 3.94 and 3.15 for ASF. For IA and EV, only within-herd R0 values were estimated at 8.65 and 1.3, respectively. Diseases with high R0 values highlight the need for prompt detection and response to outbreaks. Continuous monitoring and evaluation of pathogen transmissibility are crucial for enhancing disease surveillance and reducing the impact of livestock diseases. [ABSTRACT FROM AUTHOR]

Simple Summary: ASF remains a significant concern for the Philippines as it has impacted the swine industry and food security. It causes high mortality rates, leading to decreased pork production, high prices of pork and pork products, and financial losses for farmers and stakeholders, especially for the livelihoods of many small-scale pig farmers in the Philippines. Since its first appearance in 2019, the government has implemented strict measures to control the spread of the disease that include enhanced surveillance, strict biosecurity and quarantine protocols, restricted movement of live pigs and pork products, and culling of infected and at-risk pigs. Ongoing surveillance and cooperation between industry stakeholders, government agencies, and research institutions and collaboration with international organizations and experts to develop enhanced strategies for ASF control and prevention are necessary to mitigate ASF's impacts on the swine industry. Moreover, public awareness campaigns and support for affected farmers are continuously in place to combat ASF in the Philippines. African swine fever (ASF), a highly contagious disease of swine, has posed a significant global threat to the swine industry. As an archipelago, the Philippines has a geographic advantage when it comes to the risk of ASF transmission. However, since its introduction to the Philippines in 2019, it has proliferated not only in backyard and commercial farms but also in wild pig populations. While certain parts of the country were more affected than others, the epidemiologic features of ASF necessitate that all affected areas must be closely monitored and that confirmed cases be treated with the utmost care. With the very limited data on ASF epidemiology and surveillance in the Philippines, future efforts to combat ASF must place even greater emphasis on improved prevention and control strategies. It is worth mentioning that the government's efforts toward comprehensive ASF surveillance and epidemiological investigation into the possible ASFV sources or transmission pathways are the most important measures in the prevention and control of ASF outbreaks. This review article provides a comprehensive overview of the current swine industry and ASF situation in the Philippines, which includes its epidemiology, surveillance, prevention, and control strategies. [ABSTRACT FROM AUTHOR]

Wild animals appear to be a key factor in the occurrence, transmission and prevalence of a myriad of contagious animal diseases, being natural reservoirs, vectors or both. This role is played by wild boars in the African swine fever (ASF) transmission to domestic pigs. ASF entered the European Union in 2014 and since then lots of measures have been implemented to bring the disease under control. Bulgaria also tried to introduce new measures for reduction of wild boar populations, regarding ASF through legislative amendments. Proposals in the Bulgarian Law on hunting and game protection from 2020 tried to make legitimate wild boar culling with some unselective approaches like the use of baits with chemical poisonous or intoxicating substances. This provoked the authors to study the experience of other countries on particular toxicants used for baiting for control of wild boar populations. We investigated the available scientific literature on the selective character of chemical baiting and the effect on non-target species. Moreover, the participation of different stakeholders in the process of development and implementation of the mentioned measures was discussed. Thus, proposals were made for better preparatory, scientific and efficiency investigation at the preliminary stage of animal disease control measures development. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Preventive Veterinary Medicine / Zhongguo Yufang Shouyi Xuebao is the property of Chinese Journal of Preventive Veterinary Medicine Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Stomach ulcers are relatively common in pigs raised in modern large-scale farms. They can result in reduced daily weight gain, reduced feed intake, and sudden death, resulting in significant economic losses. They also belong to the most common findings in the stomach of pigs at slaughterhouses and are among the most important causes of peracute mortality, associated with bleeding into the digestive system of pigs. The aim of this article was to provide an overview of the most important etiological factors, and pathogenesis of gastric ulcers in pigs. [ABSTRACT FROM AUTHOR]

Botanicals exhibit promising impacts on intestinal health, immune-regulation, and growth promotion in weaned pigs. However, these benefits may vary depending on major active components in the final feed additive products. Therefore, this study aimed to investigate two types of botanical blends (BB) that were comprised of 0.3% capsicum oleoresin and 12% garlic extracts from different sources on performance, diarrhea, and health of weaned piglets experimentally infected with a pathogenic Escherichia coli F18. Sixty weanling pigs (7.17 ± 0.97 kg body weight (BW)) blocked by weight and gender were assigned to one of five dietary treatments: negative control (NC), positive control (PC), or dietary supplementation with 100 mg/kg of BB1, 50 mg/kg or 100 mg/kg of BB2. This study lasted 28 d with 7 d before and 21 d after the first E. coli inoculation (day 0). All pigs, except negative control, were orally inoculated with 1010 cfu E. coli F18/3-mL dose for 3 consecutive days. Blood samples were collected periodically to analyze systemic immunity. Intestinal tissues and mucosa were collected on days 5 and 21 PI for analyzing histology and gene expression. All data, except for frequency of diarrhea, were analyzed by ANOVA using the PROC MIXED of SAS. The Chi-square test was used for analyzing frequency of diarrhea. Escherichia coli infection reduced (P < 0.05) growth rate and feed intake and increased (P < 0.05) frequency of diarrhea of weaned pigs throughout the experiment. Supplementation of 100 mg/kg BB1 or BB2 alleviated (P < 0.05) frequency of diarrhea of E. coli challenged pigs during the entire experiment. Escherichia coli infection also enhanced (P < 0.05) serum TNF-α and haptoglobin concentrations on day 4 post-inoculation (PI) but reduced (P < 0.05) duodenal villi height and area on day 5 PI, while pigs supplemented with 100 mg/kg BB1 or BB2 had lower (P < 0.05) serum TNF-α than pigs in PC on day 4 PI. Pigs fed with 100 mg/kg BB2 had higher (P < 0.05) jejunal villi height than pigs in PC on day 5 PI. Pigs fed with 100 mg/kg BB2 had reduced (P < 0.05) gene expression of IL1B, PTGS2, and TNFA in ileal mucosa than pigs in PC on day 21 PI. In conclusion, dietary supplementation of botanical blends at 100 mg/kg could enhance disease resistance of weaned pigs infected with E. coli F18 by enhancing intestinal morphology and regulating local and systemic immunity of pigs.

Background: Monitoring of infectious diseases on swine farms requires a high diagnostic sensitivity and specificity of the test system. Moreover, particularly in cases of swine influenza A virus (swIAV) it is desirable to include characterization of the virus as precisely as possible. This is indispensable for strategies concerning prophylaxis of swIAV and furthermore, to meet the requirements of a purposeful monitoring of newly emerging swIAV strains in terms of vaccine design and public health. Within the present cross-sectional study, we compared the diagnostic value of group samples (wipes of surfaces with direct contact to mouth/nose, dust wipes, udder skin wipes, oral fluids) to individual samples (nasal swabs, tracheobronchial swabs) for both swIAV identification and characterization. Sampling included different stages of pig production on 25 sow farms with attached nursery considered as enzootically infected with swIAV. Firstly, samples were analyzed for IAV genome and subsequently samples with Ct-values < 32 were subtyped by multiplex RT-qPCR. Results: Nasal swabs of suckling piglets and nursery pigs resulted in a higher odds to detect swIAV (p < 0.001) and to identify swIAV subtypes by RT-qPCR (p < 0.05) compared to nasal swabs of sows. In suckling piglets, significant higher rates of swIAV detection could be observed for nasal swabs (p = 0.007) and sow udder skin wipes (p = 0.036) compared to contact wipes. In the nursery, group sampling specimens were significantly more often swIAV positive compared to individual samples (p < 0.01), with exception of the comparison between contact wipes and nasal swabs (p = 0.181). However, in general nasal swabs were more likely to have Ct-value < 32 and thus, to be suitable for subtyping by RT-qPCR compared to dust wipes, contact wipes, udder skin wipes and tracheobronchial swabs (p < 0.05). Interestingly, different subtypes were found in different age groups as well as in different specimens in the same holding. Conclusion: Although population-based specimens are highly effective for swIAV monitoring, nasal swabs are still the preferable sampling material for the surveillance of on-farm circulating strains due to significantly higher virus loads. Remarkably, sampling strategies should incorporate suckling piglets and different age groups within the nursery to cover as many as possible of the on-farm circulating strains. [ABSTRACT FROM AUTHOR]

Human health is dependent on food safety and, therefore, on the health of farm animals. One of the most significant threats in regard to swine diseases is African swine fever (ASF). Infections caused by porcine circoviruses (PCVs) represent another important swine disease. Due to the ubiquitous nature of PCV2, it is not surprising that this virus has been detected in ASFV-affected pigs. However, recent data indicate that coinfection of PCV3 and ASFV also occurs. It is still unclear whether PCV infection plays a role in ASFV infection, and that subject requires further analysis. The aim of this study was to assess whether PCV3 and PCV4 are present in the wild boar population in Poland (real-time PCR). The analysis was performed on wild boar samples collected for routine ASF surveillance in Poland, between 2018 and 2021. By extension, the obtained data were compared in regard to ASFV presence in these samples, thus investigating the odds of ASFV infection on the grounds of the PCV carrier state in free-ranging Suidae in Poland. In addition, sequencing of PCV3 and phylogenetic analysis were performed, based on a full genome and a capsid gene. In the current study, we demonstrated the high prevalence of PCV3 in the wild boar population in Poland; meanwhile, PCV4 was not detected. The odds of ASFV infection on the grounds of the PCV3 carrier state in free-ranging Suidae in Poland was more than twice as high. Ten full genome sequences of PCV3 were obtained, all of them belonging to clade 3a. The similarity between them was in the range of 98.78–99.80%. [ABSTRACT FROM AUTHOR]

African swine fever (ASF) is a deadly disease of swine currently causing a worldwide pandemic, leading to severe economic consequences for the porcine industry. The control of disease spread is hampered by the limitation of available effective vaccines. Live attenuated vaccines (LAVs) are currently the most advanced vaccine prototypes, providing strong protection against ASF. However, the significant advances achieved using LAVs must be complemented with further studies to analyze vaccine-induced immunity. Here, we characterized the onset of cross-protective immunity triggered by the LAV candidate BA71ΔCD2. Intranasally vaccinated pigs were challenged with the virulent Georgia 2007/1 strain at days 3, 7 and 12 postvaccination. Only the animals vaccinated 12 days before the challenge had effectively controlled infection progression, showing low virus loads, minor clinical signs and a lack of the unbalanced inflammatory response characteristic of severe disease. Contrarily, the animals vaccinated 3 or 7 days before the challenge just showed a minor delay in disease progression. An analysis of the humoral response and whole blood transcriptome signatures demonstrated that the control of infection was associated with the presence of virus-specific IgG and a cytotoxic response before the challenge. These results contribute to our understanding of protective immunity induced by LAV-based vaccines, encouraging their use in emergency responses in ASF-affected areas. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Veterinary Journal / Revue Vétérinaire Canadienne is the property of Canadian Veterinary Medical Association and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Swine viral diseases have the capacity to cause significant losses and affect the sector's sustainability, a situation further exacerbated by the lack of antiviral drugs and the limited availability of effective vaccines. In this context, a novel point-of-care (POC) diagnostic device incorporating photonic integrated circuits (PICs), microfluidics and information, and communication technology into a single platform was developed for the field diagnosis of African swine fever (ASF) and classical swine fever (CSF). The device targets viral particles and has been validated using oral fluid and serum samples. Sensitivity, specificity, accuracy, precision, positive likelihood ratio (PLR), negative likelihood ratio (NLR), and diagnostic odds ratio (DOR) were calculated to assess the performance of the device, and PCR was the reference method employed. Its sensitivities were 80.97% and 79%, specificities were 88.46% and 79.07%, and DOR values were 32.25 and 14.21 for ASF and CSF, respectively. The proposed POC device and PIC sensors can be employed for the pen-side detection of ASF and CSF, thus introducing novel technological advancements in the field of animal diagnostics. The need for proper validation studies of POC devices is highlighted to optimize animal biosecurity. [ABSTRACT FROM AUTHOR]

Background: Gamithromycin is an effective therapy for bovine and swine respiratory diseases but not utilized for rabbits. Given its potent activity against respiratory pathogens, we sought to determine the pharmacokinetic profiles, antimicrobial activity and target pharmacokinetic/pharmacodynamic (PK/PD) exposures associated with therapeutic effect of gamithromycin against Pasteurella multocida in rabbits. Results: Gamithromycin showed favorable PK properties in rabbits, including high subcutaneous bioavailability (86.7 ± 10.7%) and low plasma protein binding (18.5–31.9%). PK analysis identified a mean plasma peak concentration (Cmax) of 1.64 ± 0.86 mg/L and terminal half-life (T1/2) of 31.5 ± 5.74 h after subcutaneous injection. For P. multocida, short post-antibiotic effects (PAE) (1.1–5.3 h) and post-antibiotic sub-inhibitory concentration effects (PA-SME) (6.6–9.1 h) were observed after exposure to gamithromycin at 1 to 4× minimal inhibitory concentration (MIC). Gamithromycin demonstrated concentration-dependent bactericidal activity and the PK/PD index area under the concentration-time curve over 24 h (AUC24h)/MIC correlated well with efficacy (R2 > 0.99). The plasma AUC24h/MIC ratios of gamithromycin associated with the bacteriostatic, bactericidal and bacterial eradication against P. multocida were 15.4, 24.9 and 27.8 h in rabbits, respectively. Conclusions: Subcutaneous administration of 6 mg/kg gamithromycin reached therapeutic concentrations in rabbit plasma against P. multocida. The PK/PD ratios determined herein in combination with ex vivo activity and favorable rabbit PK indicate that gamithromycin may be used for the treatment of rabbit pasteurellosis. [ABSTRACT FROM AUTHOR]

African swine fever (ASF) is an acute, hemorrhagic, and severe infectious disease caused by the ASF virus (ASFV). ASFV has evolved multiple strategies to escape host antiviral immune responses. Here, we reported that ASFV pB318L, a trans-geranylgeranyl-diphosphate synthase, reduced the expression of type I interferon (IFN-I) and IFN-stimulated genes (ISGs). Mechanically, pB318L not only interacted with STING to reduce the translocation of STING from the endoplasmic reticulum to the Golgi apparatus but also interacted with IFN receptors to reduce the interaction of IFNAR1/TYK2 and IFNAR2/JAK1. Of note, ASFV with interruption of B318L gene (ASFV-intB318L) infected PAMs produces more IFN-I and ISGs than that in PAMs infected with its parental ASFV HLJ/18 at the late stage of infection. Consistently, the pathogenicity of ASFV-intB318L is attenuated in piglets compared with its parental virus. Taken together, our data reveal that B318L gene may partially affect ASFV pathogenicity by reducing the production of IFN-I and ISGs. This study provides a clue to design antiviral agents or live attenuated vaccines to prevent and control ASF. Author summary: African swine fever virus (ASFV) causes a highly lethal swine disease in many countries, severely affecting the pig industry. Until now, African swine fever has caused substantial economic losses to the world pig industry because of the lack of commercial vaccines and drugs. Therefore, there is an urgent need for efficient commercialized vaccines to prevent and control the disease. It has been reported that the ability of ASFV to escape host antiviral immune responses is closely related to its pathogenicity, and deletion of ASFV virulence-related gene(s) may contribute to the development of attenuated live vaccines. In this study, we found that pB318L reduces the production of IFN-I induced by cGAS-STING and ISGs induced by IFN-α. As a virulence-related gene, interruption of B318L significantly attenuated ASFV pathogenicity. Our findings provide a new clue to understand the functions of ASFV-encoded pB318L and its role in viral infection-induced pathogenesis, which might help design antiviral agents or live attenuated vaccines to control ASF. [ABSTRACT FROM AUTHOR]

Porcine reproductive and respiratory syndrome (PRRS), an important viral disease of swine caused by PRRS virus (PRRSV) was first confirmed in Nepal in 2013. Since then, the virus has spread throughout the country and has now become endemic affecting the pig production nationally. However, molecular characterization of circulating strains has not been done in Nepal yet. In the present study, serum samples were collected from outbreak areas of different districts of Nepal and samples positive for PRRSV by ELISA were sent to Animal and Plant Health Agency (APHA), United Kingdom for sequence analysis. Out of 35 samples that were sent to APHA, only one sample was found positive by PCR and subjected to sequence analysis based on ORF5, ORF7 and Nsp2. The results from the phylogenetic analysis demonstrated that the PRRSV strain belongs to PRRSV-2 and lineage 8 strain. The sequences from the Nepalese PRRSV strain revealed a high degree of similarity with the strains isolated from India, China and Vietnam, with the closest genetic relatedness to the Indian isolates from 2020 and 2018. This is the first study on molecular characterization of PRRS virus circulating in Nepal. Further studies on strains circulating in Nepal are very essential to understand the virus diversity, its spread and evolution. [ABSTRACT FROM AUTHOR]

The main objective of this study was to present data on the current situation and future trends of pig meat production in the European Union-27 (EU). Pig production has played an important social and economic role for centuries in many states of the EU. In 2022, pig meat production in the EU reached 23 M tons, which represented 21% of total production worldwide. The two key reasons that justify such amount of pork produced, are the acceptance and high consumption of the meat by the local population and the high quality of the meat produced which facilitated pork export. However, current data show a reduction in pork production for the last three years, as a consequence of a series of events that include i) problems with the chain of ingredients supply, ii) uncontrolled increase in African Swine Fever (ASF) outbreaks, iii) fast recovery of pig production in China, iv) increasing concerns by the rural population on the high cost to meet future requirements of the EU legislation on farm management, environmental sustainability and animal welfare, v) increased cost of all inputs involved in pig production and vi) limited interest of the new farmer generation to work on the pig sector. Consequently, pork production is expected to decrease in the EU for the next years, although sales will be maintained at a relative high level because pork is the meat preferred by local consumers in most EU countries. In order to maintain the favourable position of the pork industry in the near future, strategies to implement include: i) maintain the quality of the meat destinated to export markets, ii) improve the control of outbreaks of ASF and other swine diseases, iii) implementation of technological innovations to improve working conditions making more attractive to work in the pork sector of the food chain to the new generation of farmers and workers. [ABSTRACT FROM AUTHOR]

Streptococcus suis serotype 2 (SS2) is an important porcine pathogen that causes diseases in both swine and human. For rapid SS2 identification, a novel latex agglutination test (LAT) based on heavy-chain variable domain antibody (VH) was developed. Firstly, the soluble 47B3 VH antibody fragment from a phage display library, in which cysteine residues were engineered at the C-terminus, was expressed in Escherichia coli. The purified protein was then gently reduced to form monomeric soluble 47B3 VH subsequently used to coat with latex beads by means of site-specific conjugation. The resulting VH-coated beads gave a good agglutination reaction with SS2. The LAT was able to distinguish S. suis serotype 2 from serotype 1/2, which shares some common sugar residues, and showed no cross-reaction with other serotypes of S. suis or other related bacteria. The detection sensitivity was found to be as high as 1.85x106 cells. The LAT was stable at 4°C for at least six months without loss of activity. To the best of our knowledge, this is the first LAT based on a VH antibody fragment that can be considered as an alternative for conventional antibody-based LAT where VHs are the most favored recombinant antibody. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Porcine reproductive and respiratory syndrome (PRRS) is a significant disease of swine. The purpose of this study was to determine whether application of a comprehensive, science-based approach to breeding herd biosecurity, known as next-generation biosecurity (NGB), could reduce PRRS incidence risk across a large commercial production company. ANIMALS: Pigs (381,404 sows across 76 breeding herds). METHODS: From 2009 to 2020, the annual incidence risk of PRRS in sow farms managed by the same company averaged 33%, ranging from 20% to 50%. To measure the effect of NGB on PRRS incidence risk, a retrospective cohort study was conducted from July 1, 2021, to June 30, 2023, across breeding herds managed by the same company. During the analysis, 2 groups of herds emerged: those that implemented protocols forall phases of NGB (NGB COMPLETE), and those that implemented all described protocols of biosecurity except for air filtration (NGB INCOMPLETE). RESULTS: During the 2-year assessment period, 56 breeding herds were classified as NGB COMPLETE, while 20 herds were NGB INCOMPLETE. The PRRS incidence risk in NGB COMPLETE herds was 8.9% as compared to 40.0% in NGB INCOMPLETE herds. From disease year 1 (July 1, 2021, to June 30, 2022) and disease year 2 (July 1, 2022, to June 30, 2023), system-wide PRRS incidence risk was 8.6% and 9.2%, respectively. The association between NGB status and PRRS incidence risk for the 2-year period was statistically significant at a P value of .006. CLINICAL RELEVANCE: Results of the present report provided evidence that improvements in biosecurity result in lower PRRS incidence risk under large-scale commercial swine production conditions. [ABSTRACT FROM AUTHOR]

African Swine Fever (ASF) is a highly lethal viral disease in swine, with mortality rates approaching 100%. The disease has spread to many swine-producing countries, leading to significant economic losses and adversely impacting global food security. Extensive efforts have been directed toward developing effective ASF vaccines. Among the vaccinology approaches tested to date, live-attenuated virus (LAV) vaccines produced by rational deleting virulence genes from virulent African Swine Fever Virus (ASFV) strains have demonstrated promising safety and efficacy in experimental and field conditions. Many gene-deleted LAV vaccine candidates have been generated in recent years. The virulence genes targeted for deletion from the genome of virulent ASFV strains can be categorized into four groups: Genes implicated in viral genome replication and transcription, genes from the multigene family located at both 5′ and 3′ termini, genes participating in mediating hemadsorption and putative cellular attachment factors, and novel genes with no known functions. Some promising LAV vaccine candidates are generated by deleting a single viral virulence gene, whereas others are generated by simultaneously deleting multiple genes. This article summarizes the recent progress in developing and characterizing gene-deleted LAV vaccine candidates. [ABSTRACT FROM AUTHOR]

Background: Senecavirus A (SVA) causes an emerging vesicular disease (VD) with clinical symptoms indistinguishable from other vesicular diseases, including vesicular stomatitis (VS), foot-and-mouth disease (FMD), and swine vesicular disease (SVD). Currently, SVA outbreaks have been reported in Canada, the U.S.A, Brazil, Thailand, Vietnam, Colombia, and China. Based on the experience of prevention and control of FMDV, vaccines are the best means to prevent SVA transmission. Results: After preparing an SVA inactivated vaccine (CH-GX-01-2019), we evaluated the immunogenicity of the SVA inactivated vaccine mixed with Imject® Alum (SVA + AL) or Montanide ISA 201 (SVA + 201) adjuvant in mice, as well as the immunogenicity of the SVA inactivated vaccine combined with Montanide ISA 201 adjuvant in post-weaned pigs. The results of the mouse experiment showed that the immune effects in the SVA + 201 group were superior to that in the SVA + AL group. Results from pigs immunized with SVA inactivated vaccine combined with Montanide ISA 201 showed that the immune effects were largely consistent between the SVA-H group (200 µg) and SVA-L group (50 µg); the viral load in tissues and blood was significantly reduced and no clinical symptoms occurred in the vaccinated pigs. Conclusions: Montanide ISA 201 is a better adjuvant choice than the Imject® Alum adjuvant in the SVA inactivated vaccine preparation, and the CH-GX-01-2019 SVA inactivated vaccine can provide effective protection for pigs. [ABSTRACT FROM AUTHOR]

Background: Respiratory diseases, including the multifactorial "swine respiratory disease complex," have a significant impact on swine production. Recently, a condition manifesting primarily in the trachea, known as hemorrhagic tracheitis syndrome (HTS), has been described in pigs. HTS is characterized by severe coughing and high mortality in finishing pigs. Case Description: This report presents the first case of HTS in an adult male pig from a Portuguese farm. The animal died without any previous clinical signs. Necropsy revealed significant thickening of the trachea. Fibrinous necrotic hemorrhagic tracheitis was identified through histopathological analysis, but no bacterial infectious agents were detected during microbiological examination. Conclusion: This case underscores the need for comprehensive research, including systematic necropsies and histopathological assessments, to understand the actual prevalence of the disease, elucidate the etiology, and develop effective interventions for HTS in swine productions. [ABSTRACT FROM AUTHOR]

In the European Union, gastrointestinal disease in pigs is the main indication for the use of colistin, but large-scale epidemiologic data concerning the frequency of mobile colistin resistance (mcr) genes in pig-associated pathotypes of Escherichia coli (E. coli) are lacking. Multiplex polymerase chain reactions were used to detect virulence-associated genes (VAGs) and mcr-1–mcr-10 genes in 10,573 porcine E. coli isolates collected in Germany from July 2000 to December 2021. Whole genome sequencing was performed on 220 representative mcr-positive E. coli strains. The total frequency of mcr genes was 10.2%, the most frequent being mcr-1 (8.4%) and mcr-4 (1.6%). All other mcr genes were rarely identified (mcr-2, mcr-3, mcr-5) or absent (mcr-6 to mcr-10). The highest frequencies of mcr genes were found in enterotoxigenic and shiga toxin-encoding E. coli (ETEC/STEC hybrid) and in edema disease E. coli (EDEC) strains (21.9% and 17.7%, respectively). We report three novel mcr variants, mcr-1.36, mcr-4.8, and mcr-5.5. In 39 attaching and effacing E. coli (AEEC) isolates analyzed in our study, the eae subtype β1 was the most prevalent (71.8%). Constant surveillance for the presence of mcr genes in various sectors should consider the different frequency of mcr-positive isolates in pathogenic E. coli. [ABSTRACT FROM AUTHOR]

Simple Summary: Salmonella is a pathogen of worldwide public health concern, responsible for gastroenteritis and sometimes other health complications. Humans can be infected by eating contaminated pig products. On farms, pigs are usually asymptomatic carriers of Salmonella, making it difficult to detect the disease clinically. Some methods for controlling this microorganism are used on the farm, but their effectiveness varies between studies. Probiotics could be a reliable option in this context, reducing the presence of Salmonella in the pig's intestinal tract while modulating its microbiota. The carriage of Salmonella in pigs is a major concern for the agri-food industry and for global healthcare systems. Humans could develop salmonellosis when consuming contaminated pig products. On the other hand, some Salmonella serotypes could cause disease in swine, leading to economic losses on farms. The purpose of the present study was to characterize the anti-Salmonella activity of a novel Bacillus-based probiotic using a bioreactor containing a piglet-derived intestinal microbiota. Two methods of probiotic administration were tested: a single daily and a continuous dose. Salmonella enumeration was performed using selective agar at T24h, T48h, T72h, T96h and T120h. The DNA was extracted from bioreactor samples to perform microbiome profiling by targeted 16S rRNA gene sequencing on Illumina Miseq. The quantification of short-chain fatty acids (SCFAs) was also assessed at T120h. The probiotic decreased Salmonella counts at T96 for the daily dose and at T120 for the continuous one. Both probiotic doses affected the alpha and beta diversity of the piglet-derived microbiota (p < 0.05). A decrease in acetate concentration and an increase in propionate proportion were observed in the continuous condition. In conclusion, the tested Bacillus-based product showed a potential to modulate microbiota and reduce Salmonella colonization in a piglet-derived intestinal microbiota and could therefore be used in vivo. [ABSTRACT FROM AUTHOR]

Flunixin meglumine is a nonsteroidal anti‐inflammatory drug approved to manage pyrexia associated with swine respiratory disease. In the United States, no analgesic drugs are approved for use in swine by the FDA, although they are needed to manage painful conditions. This study evaluated the pharmacokinetics and relative bioavailability of intranasal versus intramuscular flunixin in grower pigs. Six pigs received 2.2 mg/kg flunixin either intranasally via atomizer or intramuscularly before receiving flunixin via the opposite route following a 5‐day washout period. Plasma samples were collected over 60 h and analysed using ultra‐performance liquid chromatography and tandem mass spectrometry to detect flunixin plasma concentrations. A non‐compartmental pharmacokinetic analysis was performed. The median Cmax was 4.0 μg/mL and 2.7 μg/mL for intramuscular and intranasal administration, respectively, while the median AUCinf was 6.9 h μg/mL for intramuscular administration and 4.9 h μg/mL for intranasal administration. For both routes, the median Tmax was 0.2 h, and flunixin was detectable in some samples up to 60 h post‐administration. Intranasal delivery had a relative bioavailability of 88.5%. These results suggest that intranasal flunixin has similar, although variable, pharmacokinetic parameters to the intramuscular route, making it a viable route of administration for use in grower swine. [ABSTRACT FROM AUTHOR]

Aujeszky's Disease (AD) is a highly infectious swine disease caused by Suid herpesvirus 1 (SuHV 1). The present study evaluated the biosafety of commercial swine farms and carried out the first serological survey for Aujeszky's Disease in Espírito Santo State, Brazil. A total of 55 farms in 27 municipalities of the state were selected, where 416 swine serum samples were collected to be submitted to serological diagnosis for AD. Finally, a survey was carried out using a questionnaire to obtain information on the biosecurity of the farms. The results by the ELISA technique indicated the absence of antibodies for AD. Regarding the biosecurity of the farms, 56.4% of the farms did not meet the requirement of internal isolation, 67.3% did not have changing rooms, 72.7% did not provide specific clothing for employees and visitors, 85.5% did not require visitors bathe to access the sheds and only 10.9% of the farms controlled the flow of visitors and vehicles accessing the property. Another noteworthy factor is that only 25.5% of the farms had an area to quarantine replacement animals and 69.1% had an access ramp located close to the animal pens. With the results, it was concluded that there is a need to improve biosecurity measures on commercial farms in the state of Espírito Santo and that there was no presence of Aujeszky's Disease in the evaluated animals. [ABSTRACT FROM AUTHOR]

Cryptosporidium, an enteric protozoan parasite, poses economic losses in animal production and has zoonotic potential. This study aimed to determine the prevalence of cryptosporidium and associated risk factors in local pig breeds within Donga Local Government Area of Taraba State, Nigeria. A cross-sectional study was conducted, and a total of 384 faecal samples were collected from pigs in eight sampling sites. The samples were examined using the modified Ziehl-Neelsen staining technique. The results showed an overall prevalence of 27.9% (107/384) for cryptosporidium oocysts. The prevalence was significantly higher in pre-weaned piglets (64%) compared to post-weaned (26.9%) and adult pigs (24.14%). Female pigs had a significantly higher prevalence (49.21%) than males (17.4%), and diarrhoeic pigs had a significantly higher prevalence (55.2%) than non-diarrhoeic (22.9%). The prevalence was higher in the rainy season (42.4%) than in the dry season (10.3%). The detection of Cryptosporidium spp. oocysts in the faeces of pigs suggests that these animals may serve as potential reservoirs and shedders of this protozoan parasite, contaminating the environment and serving as a source of infection to other animals and humans. Adequate personal and environmental hygiene, along with prompt veterinary care, should be intensified. [ABSTRACT FROM AUTHOR]