Search Results (480)

Type I (slow-twitch) muscle fibers differ in proportion among skeletal muscles, but their local spatial organization remains poorly characterized. This preliminary cross-sectional study investigated whether muscle-specific characteristics were reflected not only in the proportion of slow myosin-positive fibers but also in their clustering architecture. The longissimus, psoas major, semitendinosus, and triceps brachii muscles were collected from pigs at 4 weeks and 6 months of age. All six pigs were female, and live body-weight records were unavailable. Slow myosin-positive muscle fibers (slow fibers) were identified by immunohistochemistry, and adjacent positive fibers were defined as clusters. In pairwise tests at 6 months, the proportion of slow fibers was significantly higher in the psoas major than in the other three muscles, although the main effect of muscle across both ages was not significant (p = 0.0565). Slow fibers occurred as either isolated fibers or contiguous clusters in all muscles, but their clustering patterns differed markedly. Notably, the psoas major muscle had a significantly higher proportion of slow fibers in large clusters than the longissimus and semitendinosus muscles at 6 months of age. These findings suggest that muscle-specific characteristics are reflected not only in the proportion of slow fibers but also in their local spatial arrangement. Thus, clustering architecture may provide a complementary histological parameter for characterizing muscle-specific tissue organization in porcine skeletal muscle. Full article

Peripheral blood mononuclear cells (PBMCs) are the most immunologically active and readily accessible fraction of whole blood, and they initiate host immune responses following infection and vaccination. Since PBMC transcriptomes capture diverse host–pathogen interactions, they offer a promising tool to uncover the genetic drivers of viral resistance and tolerance. As a detailed case study of this principle, we examine porcine reproductive and respiratory syndrome (PRRS), which remains one of the most economically important viral diseases of swine worldwide. Following PRRS virus (PRRSV) exposure, pigs rely on two complementary defense strategies: resistance, the capacity to limit viral replication, and tolerance, the capacity to sustain performance despite infection. Since resistance and tolerance phenotypes are difficult to measure directly through experimental challenge, indirect immune-trait measurements collected after vaccination offer a practical alternative. Most transcriptomic studies of the host response to PRRSV have focused on respiratory tissues, reflecting the virus’s tropism for pulmonary macrophages. However, intramuscularly delivered modified-live PRRSV vaccine reaches the bloodstream, bypassing the lung, so PBMCs, as the frontline defense system, mount the earliest measurable innate response. This review synthesizes the current literature on PBMC transcriptome models for deciphering innate resistance and tolerance to viral disease, using PRRS as our principal worked example; presents our own approach to profiling PBMCs after PRRSV vaccination; and outlines how the field has advanced since the original candidate-gene and QTL studies of the 2010s, including the recent FDA approval of the first CD163 gene-edited PRRSV-resistant pig line, and the emergence of single-cell and multi-tissue PBMC atlases, before considering how the same PBMC-based approach could extend to other host–virus interactions. Full article

Excessive body fat deposition during pregnancy is believed to have an adverse effect on the reproductive performance of sows. Feed intake regulation (REG) is an effective method to modulate energy intake and fat deposition. This study aimed to explore the impact of feed intake and body fat deposition on reproductive performance. A total of 24 Shaziling sows (parity 3–6) were divided into two groups based on their BF on day 30 of gestation, and subsequently randomly assigned to control (CON) and REG groups: (1) BF between 12 and 16 mm (LB-CON, n = 6), (2) BF between 12 and 16 mm (LB-IF, n = 6), (3) BF between 18 and 22 mm (HB-CON, n = 6), and (4) BF between 18 and 22 mm (HB-RF, n = 6). Sows in the LB-CON and HB-CON groups were fed a basic diet at a dosage of 1.88 kg/d. The LB-IF and HB-RF groups received REG and were fed a basic diet at dosages of 2.07 kg/d and 1.69 kg/d, respectively. Higher total litter weight and live litter weight were observed in HB-RF sows (p < 0.05). In addition, HB-CON sows displayed higher serum levels of IL-6, TG, and GLU when compared with LB-CON sows (p < 0.05), whereas HB-RF sows exhibited lower levels of these markers than HB-CON sows (p < 0.05). The lipid droplet area fraction was higher in HB-CON sows than in LB-CON sows (p < 0.05), and this fraction was reduced in HB-RF sows compared with HB-CON sows (p < 0.05). The placental level of TC increased in HB-CON sows when compared with LB-CON sows (p < 0.05). The placental levels of T-AOC and GPX increased in HB-RF sows when compared with HB-CON sows (p < 0.05). Moreover, the mRNA expression of FABP3 was higher in HB-CON sows when compared with LB-CON sows (p < 0.05). The mRNA expression of GLUT3 and PlGF increased in HB-RF sows when compared with HB-CON sows (p < 0.05). In addition, HB-RF sows exhibited increased Shannon, Simpson, and ACE indices when compared with HB-CON sows (p < 0.05). The characterization of the fecal microbiota revealed that HB-RF sows displayed a lower ratio of Firmicutes/Bacteroidota and an increased relative abundance of Limosilactobacillus when compared with HB-CON sows (p < 0.05). Collectively, these observations suggested that reduced feed intake in Shaziling sows with high backfat thickness improved reproductive indices, alleviated placental oxidative stress and inflammatory status, elevated placental nutrient transport and angiogenesis-related gene expression, and reshaped fecal microbiota. These results provide valuable reference for pig production. Full article

African swine fever virus (ASFV) causes African swine fever (ASF), a highly lethal disease in pigs. Vietnam has approved two ASF live-attenuated vaccines (LAVs), but their efficacy and safety remain controversial, and no reliable, highly effective commercial ASF vaccine is available yet. Humoral immunity plays an important role in protection against ASFV infection. However, there is still controversy regarding whether ASFV infection can induce antibodies with neutralizing activity. Antibody-dependent cellular cytotoxicity (ADCC), as an antibody-mediated protective mechanism, offers a novel perspective for screening protective ASFV antigens. This study evaluated five structural proteins (pCP312R, pA104R, pA151R, p17, and pF317L) as subunit vaccine candidates based on their ability to induce antibodies that inhibit viral replication and mediate ADCC. The recombinant proteins were expressed in Escherichia coli, purified, and used to immunize pigs. Immune sera collected two weeks after the third immunization were tested for their ability to inhibit ASFV replication in porcine alveolar macrophages (PAMs) using rASFV-Gluc/EGFP. ADCC activity was assessed using a stable HEK293T-p17 cell line as target cells and porcine peripheral blood mononuclear cells (PBMCs) as effectors, with cytotoxicity measured by lactate dehydrogenase release. All five recombinant proteins were successfully expressed and purified. Immunization with pCP312R, pA104R, p17, and pF317L induced the production of specific antibodies in pigs, but only anti-p17 antibodies significantly inhibited ASFV replication in PAMs. The p17 is highly conserved across different ASFV genotypes and is predicted to contain a transmembrane domain. Anti-p17 antibodies effectively mediated PBMCs to specifically kill target cells, demonstrating significant ADCC activity. Moreover, the HEK293T-p17 cell line was specifically recognized by anti-ASFV sera. These findings indicate that p17 is a dual-functional antigen capable of eliciting antibodies that both inhibit viral replication and mediate ADCC in vitro. Furthermore, we have developed an in vitro platform for screening protective ASFV antibodies based on viral inhibition and ADCC, providing candidate targets for the development of next-generation ASF subunit vaccines. Full article

To meet national and global air quality and climate ceilings, it is essential to provide farm-level decision support tools for mitigating gaseous emissions from agriculture. A major challenge is to develop reliable tools that can be adapted to country-specific conditions, particularly in countries where such tools are currently lacking, and support farmers in assessing emission mitigation measures. To address this challenge, a Prototype Decision Support Tool (PDST) for estimating and mitigating gaseous emissions at the livestock farm scale was developed based on the FarmAC whole-farm model. The PDST supports livestock farm-level assessment of carbon emissions, including CH₄ and CO₂, and nitrogen-related emissions, including N₂O and NH₃. Emissions were estimated using the IPCC 2006 Guidelines, their 2019 Refinement, and the EMEP/EEA 2023 methodology. The PDST was applied to two intensive pig farms in Greece, both with fully slatted housing and outdoor slurry tank storage, and two intensive dairy cattle farms, one in Greece and one in Poland, both using deep-litter housing with solid manure storage. For these farms, the PDST estimated total annual emissions of 1.58 and 1.54 kg CO₂eq per kg of pig live weight and 0.80 and 0.66 kg CO₂-eq per kg of raw milk, respectively. These estimates were consistent with values reported in the literature for comparable production systems and emission sources, supporting the preliminary consistency of the PDST outputs. The PDST can form the software basis to support stakeholders in choosing farm-level practices that specifically reduce emissions. Full article

As an eco-friendly strategy for improving intestinal health, production performance, and meat quality in livestock and poultry, live probiotic strains (Lactobacillus, Bifidobacterium, Bacillus), paraprobiotics and postbiotics have exhibited considerable application potential in monogastric livestock in animal husbandry. However, probiotic efficacy is commonly characterized by striking individual heterogeneity, and its intrinsic regulatory basis remains poorly understood. This review systematically summarizes the core mechanisms by which probiotics modulate meat quality, feed efficiency and small intestinal and cecal health in pigs and broilers via the gut–muscle axis, nutrient metabolic axis, and immune regulatory axis. We elucidate the heritable effects of host genetics on shaping the gut microbiome and the fundamental principles underlying genotype–probiotic (G×P) interactions, highlighting that host genetic background represents an important of differential responses to probiotics. Accordingly, we propose integrating microbial genome-wide association studies (mGWAS) and genomic selection to develop novel breeding programs targeting probiotic responsiveness, with the aim of establishing a precision breeding system for probiotic-friendly livestock and poultry. This review may facilitate the paradigm shift of probiotic applications from universal administration to precision intervention, and from single nutritional regulation to host–microbiome synergistic breeding, providing a conceptual framework and innovative strategies for the green, efficient, and sustainable development of animal husbandry. Full article

Growth traits, as core economic indicators in pig breeding, are closely associated with production costs, rearing duration, and final carcass quality and have thus consistently been a major focus of genetic improvement. This study aimed to identify candidate genes affecting Age to 120 kg live weight (AGE120), Backfat thickness at 120 kg (BF120), and Loin muscle depth at 120 kg (LMD120) in pigs. Ear tissue samples were collected from 3364 healthy adult pigs (including 558 boars and 2805 sows) from three breeds: Large White, Landrace, and Duroc. Genotyping was performed using an 80 K functional site array, and quality-controlled SNP (Single-Nucleotide Polymorphism) loci were subjected to genotype imputation, resulting in 15,447,611 loci obtained. Genome-wide association studies (GWASs) for Age to 120 kg live weight, Back fat thickness at 120 kg, and Loin muscle depth at 120 kg were conducted using a mixed linear model in Genome-wide Complex Trait Analysis (GCTA). Genes located within 500 kb upstream and downstream of significant GWAS loci were extracted using the biomaRt package in R. Furthermore, colocalization analysis was performed using expression Quantitative Trait Locus (eQTL) data of 34 tissues from the PigGTEx database to identify genes that share the same causal variant as the GWAS signals. Through integrated GWAS and eQTL colocalization analysis, in addition to five previously reported genes associated with pig growth traits (TAF11, ZC3HAV1L, ANKS1A, USP20, and TBC1D1), a set of novel, high-confidence candidate genes was identified: ZNF215, UBE2Z, HOXB7, SARDH, ADAMTSL2, ATP6V0A4, RPL10A, PGM2, and RELL1. These findings enrich our understanding of the genetic architecture underlying growth traits in pigs at heavy body weights and provide an important foundation for subsequent functional validation and molecular breeding applications. Full article

Background/Objective: African swine fever (ASF), caused by African swine fever virus (ASFV), is a highly contagious viral disease affecting domestic pigs and wild boars, causing severe economic losses. Although commercial ASF vaccines have recently been approved in Vietnam, controlling ASF transmission remains challenging. Since injection-based vaccination is impractical for wild boars, oral vaccination is considered essential. This study aimed to evaluate the safety, immunogenicity, protective efficacy, and dose-related outcomes of ASFV-G-ΔI177L/ΔLVR, a live attenuated ASFV vaccine candidate with deletion in the I177L gene and left variable region (LVR), administered orally to convention pigs. Methods: The ASFV-G-ΔI177L/ΔLVR vaccine candidate was orally administered to conventional pigs at three dose levels (10^2.25, 10^5.0, and 10^6.0 TCID₅₀/dose). At 28 days post-vaccination, pigs were challenged intramuscularly with a virulent ASFV field strain at 10^2.0 HAD₅₀/mL and monitored clinically. Protection was assessed by ASFV-specific antibody responses (p32) and survival following challenge. Results: Oral immunization was well tolerated, with no vaccine-associated clinical signs observed before challenge. Following challenge, vaccinated pigs showed different protective outcomes among the tested dose groups, with survival rates of 1/4 (10^2.25 TCID₅₀/dose), 4/4 (10^5.0 TCID₅₀/dose), and 3/4 (10^6.0 TCID₅₀/dose), respectively. Pigs that succumbed to infection showed neither detectable viremia nor ASFV-specific antibodies before challenge, suggesting incomplete vaccine uptake may have resulted in insufficient immune induction rather than an adverse effect associated with vaccination. In contrast, pigs that seroconverted prior to challenge were fully protected and exhibited lower viral loads than the control animals. Conclusions: ASFV-G-ΔI177L/ΔLVR was well tolerated as an oral live attenuated vaccine candidate and induced protective immunity against virulent ASFV challenge under the present experimental conditions. Notably, complete protection was observed in the 10^5.0 TCID₅₀/dose group, supporting the potential of this vaccine candidate for oral immunization strategies against ASF. However, the present data do not allow a definitive conclusion regarding the dose–response relationship, and further studies with larger group sizes and field-relevant models are needed to refine dose selection and practical applicability, particularly for wild boar vaccination. Full article

Avian influenza viruses continue to pose significant zoonotic and pandemic threat globally, with low-pathogenic avian influenza A(H9N2) being of particular concern due to sustained circulation in poultry, adaptability, and repeated human spillover. This study investigated the detection and genetic characterization of influenza viruses at the animal–human interface in Ghana in 2022, using a nationwide cross-sectional One Health approach. Samples were collected from poultry, pigs, the environment, and animal handlers across backyard farms, commercial farms, and live bird markets. Laboratory testing was conducted using real-time RT-PCR, while statistical associations were assessed using chi-square and logistic regression. Whole-genome sequencing and phylogenetic analysis were performed on selected positive samples. Out of 4056 samples, 1516 were poultry samples. A(H9N2) was detected exclusively in poultry, with a prevalence of 5.67%. The Northern belt recorded the highest prevalence. Live bird markets had significantly higher odds of A(H9N2) detection compared with commercial farms (odds ratio: 15.37, p < 0.0001), while backyard farms had lower odds. Environmental samples were negative. Among animal handlers, one case each of A(H3N2) and SARS-CoV-2 was identified. Phylogenetic analysis demonstrated that Ghanaian strains belonged to clade G1 and possessed mammalian-adaptive markers. These findings highlight ongoing circulation in poultry and the need for sustained One Health surveillance. Full article

Porcine group A rotavirus (PoRVA) is a significant cause of viral diarrhea in piglets, necessitating urgent global implementation of effective control strategies. This review assesses advancements in PoRVA in vitro cultivation and amplification, crucial for PoRVA vaccine development. Traditional PoRVA cultivation commonly employs primary porcine kidney cells or finite cell lines like MA-104, posing well-documented challenges in scalability, production cost, and their ability to recapitulate the natural intestinal microenvironment. Consequently, research has increasingly focused on adapting PoRVA to alternative systems, particularly immortalized porcine cell lines or physiologically relevant porcine intestinal organoids. This adaptation process, involving serial passaging, can induce genomic alterations and virulence attenuation in piglets, essential for generating live attenuated vaccine (LAV) candidates. Modern biotechnological tools, such as reverse genetics and synthetic genomics, have expedited the creation of recombinant PoRVA strains with defined antigenic profiles and enhanced in vitro growth characteristics. However, a significant concern regarding LAV candidates derived from cell culture adaptation is the risk of virulence reversion upon pig back-passage, necessitating thorough safety and genetic stability evaluations. Nevertheless, utilizing stable cell lines or organoid platforms presents a feasible and cost-effective approach for large-scale PoRVA vaccine production. Future research should focus on identifying vaccine candidates that provide broad protection and exceptional safety, with an emphasis on cross-protection against divergent epidemic genotypes, while ensuring the economic feasibility of innovative manufacturing approaches. Full article

Background/Objectives: African swine fever (ASF) is a highly lethal disease of domestic pigs and wild suids that continues to cause substantial economic losses worldwide. Despite recent progress in live attenuated ASF vaccine development, evidence supporting durable protection under repeated exposure conditions representative of endemic settings remains limited. Here, we assessed the long-term safety and protective efficacy of a live attenuated ASFV-G-ΔI177L/ΔLVR vaccine using a repeated-challenge experimental design intended to model re-exposure in ASF-endemic regions. Methods: Vaccinated pigs were subjected to homologous virulent ASF virus challenges at multiple intervals, including repeated challenges (three sequential inoculations) and single challenges administered at 8 and 12 weeks post-vaccination. Results: Across all challenge regimens, vaccinated animals survived and remained clinically healthy, including those receiving three challenges, supporting sustained protection under repeated exposure pressure. Animals challenged at 8 or 12 weeks post-vaccination likewise exhibited complete survival, indicating maintained efficacy through at least 12 weeks. No vaccine-associated adverse clinical outcomes were detected over the study period, and post-challenge viral shedding was minimal. Conclusions: Overall, these data demonstrate that the candidate live attenuated ASF vaccine provides excellent protective efficacy and confers sustained protection against homologous ASF virus infection. This result is expected to be equally applicable under repeated exposure conditions in regions with unstable ASF biosecurity, making it a sufficiently promising model experiment for field application in ASF epidemic areas. However, this is still a vaccine variant, and further studies are planned to evaluate its genomic stability and transmissibility. Full article

Highly virulent African swine fever virus (ASFV) genotype II strains have been responsible for the global epidemic in domestic pigs and are typically characterized by a hemadsorption (HAD)-positive phenotype mediated by the CD2v protein encoded by the EP402R gene. Here, we report the detection and genetic characterization of three non-HAD genotype II ASFV isolates (VNUA/ASFV/VP2023-isolate1, VNUA/ASFV/TB2024-isolate2, and VNUA/ASFV/HY2024-isolate3) recovered from whole-blood samples collected from pigs exhibiting prolonged clinical signs in northern Vietnam. Whole-genome analysis revealed nonsense mutations in the EP402R gene (G57A in isolates VNUA/ASFV/TB2024-isolate2 and VNUA/ASFV/HY2024-isolate3, and G132A in VNUA/ASFV/VP2023-isolate1), resulting in premature stop codons and a HAD-negative phenotype. Furthermore, additional genetic alterations, including deletions and frameshift mutations, were identified within multigene families (MGF110, MGF360, and MGF505), which are known to play critical roles in virulence, host range, and immune evasion. Notably, VNUA/ASFV/VP2023-isolate1 harbored a partial deletion of the I177L gene along with the insertion of an mCherry marker gene, suggesting possible evolution of the modified live ASFV-G-ΔI177L vaccine strain under field conditions. Collectively, these findings underscore the ongoing evolution and genomic plasticity of ASFV strains circulating in Vietnam. Full article

Somatic cell nuclear transfer (SCNT) in pigs has been a widely used technique for producing gene-edited pigs for biomedical research, yet its wide-spread application through serial cloning remains markedly limited. Unlike in mice, where the serial cloning can be sustained across numerous generations, in pigs it is usually limited to only a few rounds. Specifically, porcine serial cloning has not been reported beyond three consecutive generations in live-born offspring, with blastocyst development rates declining from approximately 4.4% in G1 to 1–5% in G2–G3, and live-birth cloning efficiency (offspring/recipient) dropping sharply with each successive round. Compelling evidence suggests that cumulative epigenetic instability, incomplete embryo genome activation, DNA methylation reprogramming, persistent donor-cell memory, and imprinting disruption collectively erode transcriptional integrity across generations. Although several manipulations, including epigenetic modifiers, transiently improved the early development, they failed to sustain the reprogramming across several generations. Here, we synthesize comparative advances in serial cloning across species and propose that species-specific differences in chromatin plasticity and cytoplasmic reprogramming capacity define a porcine “reprogramming ceiling”. Deciphering and overcoming this barrier will be critical for advancing sustainable livestock engineering, xenotransplantation and translational medicine biotechnology. Full article

Background: Lumpy skin disease (LSD) is caused by a Capripoxvirus. Live attenuated vaccines, which are commercially available, could be not safe because of the side effects. The aim of this study was the evaluation of the safety, immunogenicity, and effects on the qualitative and quantitative parameters of milk. The feasibility of identifying vaccinated animals using our inactivated vaccine in dairy cows was analysed. The vaccine was tested in guinea pigs as an immunogenicity predictive model. Methods: LSD virus was propagated on Madin–Darby Bovine Kidney (MDBK) cells, then inactivated and supplemented with keyhole limpet hemocyanin (KLH) protein, obtaining a positive marker vaccine. This was inoculated in guinea pigs and in dairy cows, and animal sera were analysed using enzyme-linked immunosorbent assay (ELISA) and a serum neutralisation (SN) test. Quantitative and qualitative analyses were performed on milk. Results: The vaccine was previously tested for efficacy in vaccinated calves, showing a pronounced reduction in clinical symptoms after challenge. The safety and immunogenicity obtained in calves were also confirmed in dairy cows in this study. In fact, high values of the SN test (1:20 to 1:80) and ELISA (90 and 240 S/P%) were obtained after vaccination. Moreover, high immunogenicity of the vaccine was also assessed in guinea pigs. In addition, the results of the milk analyses did not show any differences between vaccinated and control groups. The KLH was able to elicit an immune response detectable using an ELISA (3.0 and 3.5 optical density values). Finally, our vaccine could be used to reduce LSD symptoms and identify vaccinated animals. Full article

Liver transplantation remains the definitive treatment for end-stage liver disease and acute liver failure, yet a critical and persistent shortage of donor organs results in thousands of preventable deaths annually worldwide. Xenotransplantation has emerged as a potential solution to this structural deficit. This narrative review traces the evolution of liver xenotransplantation, from early non-human primate trials in the 1960s through the application of CRISPR/Cas9-driven multi-gene editing platforms in contemporary porcine donors. The immunological barriers that drove the transition from primate to porcine donors are examined, including hyperacute rejection mediated by anti-α-Gal antibodies, coagulation dysregulation and xenograft thrombotic microangiopathy. The genetic engineering strategies underlying current triple-knockout, ten-gene-edited donor pigs are reviewed alongside the preclinical non-human primate evidence establishing biological feasibility. The three pig-to-human liver xenotransplantation studies published between 2025 and 2026 are then analyzed, encompassing heterotopic auxiliary transplantation in a brain-dead decedent, extracorporeal liver cross-circulation and the first auxiliary liver xenotransplantation in a living recipient with a documented 171-day survival. These cases collectively provide preliminary evidence supporting proof-of-concept for porcine hepatic bridging therapy, with current evidence supporting a role for xenogeneic liver support as a temporary bridge to recovery or allotransplantation rather than definitive organ replacement. Xenograft thrombotic microangiopathy is identified as the principal remaining biological barrier, and the substantial translational challenges, including reproducibility, scalability and regulatory readiness that must be resolved before broader clinical application can be considered. Full article