The purpose of this study is to provide a solution for the feed utilization of table leftover food by studying the mixed solid-state fermentation technology of table leftover food and corn germ meal. The detection indicators were dry matter disappearance rate and reducing sugar content. The single factor and response surface and other experimental methods were used to optimize the process parameters of solid-state fermentation of table leftover food-corn germ meal enzyme， and the effects of cellulase addition amount and enzyme preparation X1 addition amount on the dry matter disappearancerate and sugar content of solid-state fermentation products were investigated by single factor method based on the initial fermentation conditions. The optimum addition amount of cellulase and enzyme preparation X1 and fermentation time were obtained by response surface method. Twenty-four 22-day-old Arbor Acres （AA） cockerels of similar body weight and in good health condition were randomly divided into 3 groups， which were fed the basal diet and the two experimental diets， respectively， and the metabolizable energy value was measured. The results showed that as the addition amount of cellulase increased， the content of reducing sugar and the disappearance rate of dry matter increased. When the addition amount was 10.5 g·kg^-1， the increase of dry disappearance slowed down （P>0.05）， and when the addition amount was 13.5 g·kg^-1， the increase of reducing sugar slowed. As the addition amount of enzyme preparation X1 increased， the content of reducing sugar and the disappearance rate of dry matter tended to increase as a whole. When the addition amount was 6.0 g·kg^-1， the content of reducing sugar and the disappearance rate of dry matter both showed a downward trend. With dry matter degradation rate R1 as the value， the response surface recommended the best fermentation conditions as cellulase： 10.154 g·kg^-1； Enzyme preparation X1： 90 g·kg^-1， solid fermentation time of lactic acid bacteria was 96 h. With reducing sugar R2 as the response value， the response surface recommended the fermentation conditions as cellulase： 7.842 g·kg^-1； Enzyme preparation X1： 9.0 g·kg^-1， fermentation was 96 h. The solid-state fermentation of mixing table leftover food and corn germ meal， fermenting for 72 h at 37 ℃ with moisture content of 55%， the dry matter disappearance rate increased by 19.84%， the reducing sugar content increased by 162.44·g^-1， and the metabolizable energy value increased by 17.8% compared with the control group. The results suggested that the utilization of solid-state fermentation with enzyme and bacteria not only solves the problem of difficult drying of high-moisture table leftover food but also greatly improves its nutritional value， providing a scientific basis for its feed utilization.

Getah virus （GETV） is an arbovirus that can cause reproductive failure in pregnant sows， neurological symptoms in piglets， and even death in severe cases， posing a threat to the pig industry. This study aimed to analyze the whole genome sequence and evolutionary characteristics of a GETV strain isolated from dead piglets from an infected pig farm. Metatranscriptomic sequencing was conducted to analyze pathogens in brain and lung tissues from dead piglets. Vero CCL81 cells were used to isolate GETV， and the isolated virus was identified through observation of cytopathic effect （CPE）， plaque purification， RT-PCR， indirect immunofluorescence assay （IFA）， and transmission electron microscopy. The full-length genome sequence of the isolate was determined using Sanger sequencing. The results showed that the major pathogen in the tissue samples was characterized as GETV， and the isolated strain was designated as NM2022. Its genome， excluding a poly（A） tail， has a total length of 11 689 nt. Phylogenetic analysis indicated that NM2022 belongs to the evolutionary Group III of GETV， with nucleotide homology ranging from 93.98% to 99.86%， compared to 135 of GETV strains in the GenBank database. The amino acid sequence of the E2 protein of NM2022 is highly conserved with 21 of the GETV strains， including Chinese strains HNzmd-XP2 and JS201809-2 of porcine origin， as well as the strain NMDK1813-1 of mosquito origin， except for a serine-to-alanine mutation at position 380. These findings provide a foundation for further research on the evolutionary patterns and pathogenesis mechanisms of GETV.

Establishment of a double-antigen sandwich ELISA for the detection of antibodies against classical swine fever virus （CSFV） E2 protein. The complete E2 protein sequences of CSFV and bovine viral diarrhea virus （BVDV） were aligned using BioEdit software to identify CSFV-specific epitopes. A recombinant pCDNA3.1-2×rE2-His expression vector was constructed. The 2×rE2-His protein was expressed in CHO cells， followed by thrombin cleavage to remove the His-tag. The purified His-tag-free 2×rE2 protein was used as the coating antigen， while horseradish peroxidase （HRP）-labeled 2×rE2-His protein served as the detection antigen. After systematic optimization of reaction conditions， a double-antigen sandwich ELISA method was successfully established. The specificity， sensitivity， and repeatability of the assay were evaluated， and its concordance rate with a commercial ELISA kit was compared. The optimized assay conditions were as follows： antigen coating concentration at 0.5 μg·mL^-1， serum dilution at 1∶4， and enzyme-labeled antigen dilution at 1∶40 000. The method exhibited no cross-reactivity with positive sera against other common swine pathogens， including senecavirus A （SVA）， porcine pseudorabies virus （PRV）， porcine epidemic diarrhea virus （PEDV）， foot-and-mouth disease virus （FMDV）， and porcine reproductive and respiratory syndrome virus （PRRSV）， nor with BVDV sera， which frequently causes serological cross-reactivity， demonstrating high specificity. The maximum detectable dilution ratio for antibody-positive sera reached 1∶2 048. Both intra-assay and inter-assay coefficients of variation were below 10%， indicating excellent repeatability. The concordance rate with the IDEXX CSFV Antibody Test Kit was 97.1%. To further evaluate the assay， both the established double-antigen sandwich ELISA and the IDEXX kit were used to monitor antibody kinetics in two healthy pigs immunized with CSFV C-strain vaccine combined with an E2 subunit vaccine. The developed ELISA detected antibody responses 6 days earlier than the IDEXX kit. Both methods demonstrated that antibody levels peaked at 37 days post-immunization and subsequently stabilized. In this study， a double-antigen sandwich ELISA antibody detection method for CSFV was established with high specificity， sensitivity and reproducibility， which is suitable for the clinical diagnosis and evaluation of immunization effect of swine fever.

The objective of this study was to isolate and characterize a bovine-yak origin group A rotavirus with the G8P［11］ genotype and to analyze the genetic evolutionary features of its genome. Fecal samples from diarrheic calves at a dairy farm in Sihong， Jiangsu Province， were screened for six diarrhea-associated viruses. Rotavirus （RV）-positive samples were isolated and identified using RT-PCR， indirect immunofluorescence assay （IFA）， dsRNA-PAGE， and electron microscopy. The growth kinetics and cellular tropism of the isolated strains were characterized， and their cross-species transmission potential was evaluated. Additionally， whole-genome sequencing was performed on the isolates， followed by phylogenetic tree construction to determine their G/P genotypes. A bovine rotavirus strain was successfully isolated. Inoculation onto MA104 cells induced typical cytopathic effects， including cell rounding， shrinkage， detachment， and fragmentation. The virus reacted with VP6-specific monoclonal antibodies， exhibited a 4∶2∶3∶2 genomic RNA electrophoretic pattern， and displayed characteristic wheel-shaped virions approximately 70 nm in diameter. This strain was designated JSSH2024. A one-step growth curve revealed peak viral titers （TCID₅₀） as 10^5.75·mL^-1 in MA104 cells at 18 hours post-infection. In vitro infection assays demonstrated the virus's ability to replicate in MA104， IPEC-J2， HT-29 and HCT-8 cell lines， indicating potential for cross-species transmission. Whole-genome sequencing and phylogenetic analysis identified its genotype as G8-P［11］-I2-R2-C2-M2-A13-N2-T6-E2-H3. Eight gene segments clustered closely with bovine rotaviruses， while three segments showed closer genetic affinity to yak rotaviruses， suggesting its origin as a bovine-yak reassortant virus. This study reports the first G8P［11］ bovine-yak reassortant bovine rotavirus （BoRV） in China， providing critical insights for epidemiological surveillance and vaccine development.

This study aimed to prokaryotically express the lumpy skin disease virus （LSDV） ORF132 protein and evaluate its immunogenicity. The ORF132 gene was expressed in E. coli BL21（DE3）， purified， and emulsified with Freund's adjuvant. Mice were immunized with 100 µg of the protein per dose. The results demonstrated that the ORF132 protein elicited high titers of antigen-specific total IgG and a significantly elevated level of IFN-γ secretion compared to the PBS control group. Furthermore， it induced significant lymphocyte proliferation and a high neutralizing antibody titer. These findings indicate that the ORF132 protein is an immunodominant antigen capable of inducing robust humoral and cellular immune responses in mice， providing a promising candidate for subsequent multi-antigen combination studies and bovine trials.

This study aimed to construct a safe and effective Newcastle disease virus （NDV） pseudovirus for the quality control of NDV nucleic acid detection. The P gene of NDV was amplified by RT-PCR and linked to the lentiviral expression vector PLV-Puro to construct Puro-NDV/P. Puro-NDV/P plasmids and two helper plasmids were extracted， and a total of 293T cells were transfected， and pseudovirus particles containing NDV P genes were successfully constructed. The constructed pseudovirus particles were properly diluted and lyophilized to prepare RNA-positive quality controls， and calibrated， uniformity and stability tested. A Taqman fluorescence quantitative PCR detection method was established by successfully constructing NDV P gene pseudovirus. The results showed that 15 positive quality control products were randomly selected for fluorescence RT-PCR detection， and the Ct value coefficient of variation （CV） was 0.90%， which was good uniformity. The copy number of the prepared positive quality control products was 6.58×10² copies·μL^-1. The quality controls were stored at 4 ℃， 25 ℃ for short-term storage （1 week）， and -20 ℃ for a long time （6 months）， and the Ct value was detected by fluorescence RT-PCR without significant change， and the stability was good. A real-time fluorescence RT-PCR detection method based on NDV P gene pseudovirus was established. The NDV pseudovirus prepared in this test has the advantages of good uniformity and stability， and can be used for the research and development， evaluation and quality control of NDV nucleic acid detection kits， providing a reliable tool for the standardized detection of NDV.

Phage therapy is a novel antimicrobial treatment， in order to provide new theoretical and technical support for the prevention and treatment of E. coli infections， in this study， E. coli E6 and a broad-spectrum E. coli phage named vB_EcoM_E6 were isolated from the feces of diarrheic goats， and the potency， pH stability， thermal stability， lysis spectrum， and one-step growth curves of the phage were measured by observing the phage spots and biological properties， performing whole genome sequence analysis and evaluating the phage by animal model tests. The results showed that the lysis rate of this phage in the study was as high as 70.6%， and it was relatively stable at 50 ℃ and pH 3-10 range， and the transmission electron microscopy observation results indicated that this phage belonged to the myotail phage. Genome-wide analysis showed that the phage had a total length of 137 974 bp， a CG content of 39.13%， and 247 coding sequences （CDS）. The results of the mouse model test showed that the phage had a good protective effect against E. coli infection. This study provides a good material for further research on E. coli antimicrobial agents.

This study investigated the epidemiology of Salmonella in a large-scale broiler slaughterhouse in Guangdong， China， and characterized the genomic features and potential transmission risks of the predominant serovar S.Infantis， providing evidence for targeted control. Comprehensive sampling was performed across all processing stages of the slaughterhouse， yielding Salmonella isolates that were tested for resistance to 12 antimicrobials using the agar dilution method. Thirty-four representative isolates were subjected to whole-genome sequencing （WGS） for analyses of serotype， multilocus sequence typing （MLST）， plasmid content， and resistance determinants， followed by construction of a single nucleotide polymorphism （SNP）-based phylogeny. In addition， 10 389 publicly available S.Infantis genomes were retrieved from NCBI to clarify the potential transmission risks using whole-genome multilocus sequence typing （cgMLST） and SNP pairwise distance matrix analysis. A total of 96 isolates were recovered， with an overall prevalence of 55.49% （96/173），and the highest prevalence observed in the evisceration stage （79.25%）. All isolates exhibited multidrug resistance （MDR） with highly similar resistance profiles， showing 100% resistance to ampicillin， ceftiofur， nalidixic acid， florfenicol， and sulfamethoxazole， and over 90% resistance to chloramphenicol and tetracycline. WGS revealed S.Infantis as the predominant serovar （32/34）， dominated by ST32 （30/32）. All S.Infantis isolates harbored the large IncFIB-type pESI megaplasmid， carrying diverse resistance， virulence， metal， and disinfectant resistance genes. Comparative genomic analyses indicated that the slaughterhouse isolates clustered closely with 15 global S.Infantis strains， 12 of which originated from human infections. These findings demonstrate extensive cross-contamination of Salmonella across slaughterhouse stages， with MDR S.Infantis strains harboring a wide repertoire of resistance and virulence determinants. The close phylogenetic relationship with international human-derived isolates underscores their strong transmission potential and public health threat. Enhanced monitoring and targeted control of MDR S.Infantis， particularly within poultry slaughterhouses， should be prioritized to protect food safety and public health.

Nuclear factor of activated T cells 1 （NFAT1）， as a key transcription factor regulating T cell function， may participate in the pathogenesis of malaria by mediating the T cell exhaustion. This study aims to investigate the regulatory role of NFAT1 in the progression of Plasmodium berghei ANKA infection. By inhibiting NFAT1 activity and evaluating its effects on the expression of immune checkpoint molecules—T cell immunoglobulin and mucin domain-containing protein 3 （Tim-3）， cytotoxic T lymphocyte-associated antigen-4 （CTLA-4）， and programmed cell death-1 （PD-1）—in peripheral blood and spleen of Plasmodium-infected mice， this study further explore the potential therapeutic value of targeting NFAT1 for malaria treatment. Firstly， a C57BL/6 mouse infection model was established， serum lactate levels and peripheral blood NFAT1 protein expression （Western blot） were dynamically monitored at different time points （day 0， 4 and 7）. Flow cytometry was used to detect the expression levels of Tim-3， PD-1， and CTLA-4 on CD8⁺ T cells and NK cells in peripheral blood and spleen at different time points （day 0， 4， 6 and 8）. An intervention model was subsequently constructed， followed by sample collection at 48 hours post-intervention for immunophenotypic analysis. The results indicated that the serum lactate level in the infection group was significantly higher than that in the control group at the 4th （P<0.01） and the 7th （P<0.001）. The expression of NFAT1 protein was significantly upregulated at 7 days after infection （P<0.01）. Flow cytometry analysis showed that the proportions of Tim-3⁺， CTLA-4⁺， and PD-1⁺ subsets of CD8⁺ T cells/NK cells in the spleen and peripheral blood of mice were significantly increased at 6-8 days after infection （P<0.01）. After NFAT1 inhibitor intervention， the proportion of Tim-3⁺ CD8⁺ T/NK cells in the peripheral blood was significantly decreased （P<0.01）， and the proportions of CTLA-4⁺， Tim-3⁺ CD8⁺ T cells and Tim-3⁺， PD-1⁺ NK cells in the spleen were significantly reduced （P<0.01）. Notably， the proportion of CTLA-4⁺ NK cells in the peripheral blood was abnormally elevated after inhibitor treatment （P<0.001）.In conclusion， NFAT1 inhibition can partially down-regulate the expression of immune checkpoint molecules in CD8⁺ T/NK cells， but it is accompanied by the compensatory overexpression of CTLA-4 in NK cells， which may weaken its therapeutic effect. The research suggests that NFAT1-targeted therapy needs to be optimized in combination with the dynamic regulation mechanism of immune checkpoints， providing a new research direction for malaria immunotherapy strategies.

This study aimed to evaluate the application of metatranscriptomic sequencing technology for the identification of a co-infection event involving European and North American genotypes of PRRSV. A PRRSV-positive serum sample was collected from a swine farm in Guangxi Zhuang Autonomous Region. The complete genome sequence of the virus was obtained using metatranscriptomic sequencing， and further subjected to phylogenetic and recombination analysis. Complete genome sequences of both PRRSV1-GXHZ-202408 （15 076 bp） and PRRSV2-GXHZ-202408 （14 989 bp） were successfully recovered. Phylogenetic analysis revealed that PRRSV1-GXHZ-202408 formed a novel subclade with its closest relative SC-2020-1 （GenBank： MW115431； 90.45% nucleotide identity）， while PRRSV2-GXHZ-202408 clustered within the NADC30-like group （Lineage 1.8）， sharing 88.63% nucleotide identity with the prototype NADC30 strain （MH500776）. Notably， recombination events were identified in both strains： PRRSV1-GXHZ-202408 originated from an SC-2020-1 backbone with recombination breakpoints in NSP1-NSP2 （650-2 050 nt） and ORF6 （14 131-14 570 nt） involving LV4.2.1 （AY588319） and HKEU16 （EU076704）， whereas PRRSV2-GXHZ-202408 arose from recombination between NADC30 （MH500776， major parent） and JXA1 （EF112445， minor parent） in the NSP3-NSP9 region （5 331-8 081 nt）.In this study， metatranscriptomic sequencing was employed to not only definitively identify co-circulation of PRRSV1 and PRRSV2 in the swine farm， but also to obtain complete viral genomes and precisely characterize the genetic features of circulating strains. This approach clearly analyzed the epidemic dynamics of PRRSV in the swine farm， demonstrating that metatranscriptomic sequencing serves as a powerful tool for precise prevention and control of PRRS.