Interferon (IFN), the most effective antiviral cytokine, is involved in innate and adaptive immune responses and is essential to the host defense against virus invasion. Once the host was infected by pathogens, the pathogen-associated molecular patterns (PAMPs) were recognized by the host pattern recognition receptors (PRRs), which activates interferon regulatory transcription factors (IRFs) and nuclear factor-kappa B (NF-κB) signal transduction pathway to induce IFN expression. Pathogens have acquired many strategies to escape the IFN-mediated antiviral immune response. Pestiviruses cause massive economic losses in the livestock industry worldwide every year. The immune escape strategies acquired by pestiviruses during evolution are among the major difficulties in its control. Previous experiments indicated that Erns, as an envelope glycoprotein unique to pestiviruses with RNase activity, could cleave viral ss- and dsRNAs, therefore inhibiting the host IFN production induced by viral ss- and dsRNAs. In contrast, Npro, the other envelope glycoprotein unique to pestiviruses, mainly stimulates the degradation of transcription factor IRF-3 to confront the IFN response. This review mainly summarized the current progress on mechanisms mediated by Npro of pestiviruses to antagonize IFN production.

Introduction: Porcine Parvovirus (PPV) is a significant pathogen in the pig industry, with eight genotypes, including PPV7, identified since its emergence in 2016. Co-infections with viruses such as Porcine Circovirus 2 (PCV2) and Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) pose serious risks to swine health. Thus, there is an urgent need for rapid, sensitive, and specific detection methods suitable for use in field settings or laboratories with limited resources.Methods: We developed a CRISPR/Cas12a-based assay combined with recombinase polymerase amplification (RPA) for the rapid detection of PPV7. Specific RPA primers and five CRISPR RNAs (crRNAs) were designed to target a highly conserved region within the NS1 gene of PPV7. Optimization of crRNA and single-stranded DNA (ssDNA) concentrations was performed to enhance the assay’s performance.Results: CrRNA optimization identified crRNA-05 as the optimal candidate for Cas12a-based detection of PPV7, as all synthesized crRNAs demonstrated similar performance. The optimal crRNA concentration was determined to be 200 nM, yielding consistent results across tested concentrations. For ssDNA optimization, the strongest fluorescence signal was achieved with 500 nM of the FAM-BHQ ssDNA receptor. The assay showed a minimal detection limit of 100copies/μl for PPV7, confirmed through fluorescence and lateral flow detection methods. Specificity testing indicated that only PPV7 DNA samples returned positive results, confirming the assay’s accuracy. In tests of 50 lung tissue samples from diseased pigs, the RPA-Cas12a assay identified 29 positive samples (58%), surpassing the 22 positive samples (44%) detected by conventional PCR. This highlights the RPA-Cas12a method’s enhanced detection capability and its potential utility in clinical surveillance and management of PPV7 in swine populations.Discussion: The RPA-Cas12a assay effectively detects PPV7 in clinical samples, enhancing disease surveillance and control in pigs. Its adaptability to resource-limited settings significantly improves PPV7 management and prevention strategies, thereby supporting the overall health and development of the pig industry.

(1) Background:The objective of this study was to explorethe dynamic changes of gut microbiota in Simmental calves before weaning, and compared microbial composition and functionality differences between diarrhea and health calves; (2) Methods: Fourteen neonatal Simmental calves were divided into a health group (n = 8) and diarrhea group (n = 6). The rectal stool samples were collected from each calf on days 1, 3, 5, 7, 9, 12, 15, 18, 22, 26, 30, 35, and 40. The high-throughput sequencing analysis of the 16S rRNA gene V1–V9 region was conducted to explore the changes in gut microbiota over time in both groups and assess the influence of diarrhea on microbiota structure and function; (3) Results: E.coli, B.fragilis, and B.vulgatus were the top three bacterial species of pre-weaning Simmental calves.Meanwhile, the major functions of fecalmicrobiota included the “Metabolic pathways”,“Biosynthesis of secondary metabolites”,“Biosynthesis of antibiotics”, “Microbial metabolism in diverse environments”, and “Biosynthesis of amino acids”. For calves in health group, PCoA revealed that the bacterial profiles generated from days 1, 3, 5, 7, and 9 separated from days 15, 18, 22, 26, 30, 35, and 40. While the microbial profiles of calves on day 12 crossed with both clusters, suggesting that the dynamic changes of microbial structures with the increasing of ages. When compared the difference of the relative abundance of bacteria between calves in health and diarrhea groups, the results showed that the relative abundance of the beneficial L.johnsonii, F.prausnitzii, and Limosilactobacillus in the health group were significantly higher than those in the diarrhea group (p

The objective of this study was to explore the dynamic changes in the gut microbiota of Simmental calves before weaning and to compare the microbial composition and functionality between healthy calves and those with diarrhea. Fourteen neonatal Simmental calves were divided into a healthy group (n = 8) and a diarrhea group (n = 6). Rectal stool samples were collected from each calf on days 1, 3, 5, 7, 9, 12, 15, 18, 22, 26, 30, 35, and 40. High-throughput sequencing of the 16S rRNA gene V1–V9 region was conducted to examine changes in the gut microbiota over time in both groups and to assess the influence of diarrhea on microbiota structure and function. Escherichia coli, Bacteroides fragilis, and B. vulgatus were the top three bacterial species in preweaning Simmental calves. Meanwhile, the major functions of the fecal microbiota included “metabolic pathways”, “biosynthesis of secondary metabolites”, “biosynthesis of antibiotics”, “microbial metabolism in diverse environments”, and “biosynthesis of amino acids”. For calves in the healthy group, PCoA revealed that the bacterial profiles on days 1, 3, 5, 7, and 9 differed from those on days 15, 18, 22, 26, 30, 35, and 40. The profiles on day 12 clustered with both groups, indicating that microbial structure changes increased with age. When comparing the relative abundance of bacteria between healthy and diarrheic calves, the beneficial Lactobacillus johnsonii, Faecalibacterium prausnitzii, and Limosilactobacillus were significantly more abundant in the healthy group than those in the diarrhea group (p < 0.05). This study provides fundamental insights into the gut microbiota composition of Simmental calves before weaning, potentially facilitating early interventions for calf diarrhea and probiotic development.

Bovine Parainfluenza Virus Type 3 (BPIV3) is a critical pathogen in the Bovine Respiratory Disease Complex (BRDC), leading to significant economic losses in the cattle industry. However, the metabolic reprogramming induced by BPIV3 in cattle remains poorly understood. This study aimed to investigate the impact of BPIV3 infection on the serum metabolome of Simmental cattle using untargeted metabolomics and ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS/MS). The results revealed significant alterations in the lipidome, including the upregulation of phosphatidylcholine (PC) and phosphatidylglycerol (PG), and the downregulation of phosphatidylinositol (PI). Sphingolipid metabolism also showed considerable changes, with increased levels of Trihexosylceramide and D-erythro-Sphingosine C-17. Furthermore, metabolic pathway analysis identified enriched pathways related to lipid metabolism, amino acid metabolism, and energy sensing. These findings suggest that BPIV3 infection induces substantial shifts in lipid metabolism, which may facilitate viral replication and immune evasion. Our results provide a deeper understanding of the metabolic changes in BPIV3-infected cattle and propose potential targets for therapeutic intervention.