Gyrovirus galga1(GyVg1)and gyrovirus homsa1(GyH1)are two newly discovered cir-coviruses that can cause symptoms related to transmissible viral proventriculitis of chickens.These viruses have been reported in various regions worldwide.This research aims to establish a duplex real-time PCR assay capable of identifying and detecting GyVg1 and GyH1.Specific primers and probes were designed based on the conserved regions of GyVg1 and GyH1 respectively using all genome sequence data currently available in GenBank.After optimizing reaction conditions,the du-plex real-time PCR detection method was established and further validated by comparing it with a conventional PCR assay and sequencing results from an analysis of 256 clinical samples collected in 2023 across eight regions of Nanning,Guangxi.The results showed that GyVg1 and GyH1 could be identified in 1 h by the duplex real-time PCR assay and two pairs of primer probes can amplify effectively but there is no any cross reaction with other pathogens.Besides,the detection limit was determined to be 7.5 copies/μL.The correlation coefficient of standard curves exceeded 0.99,and CV for intra-and inter-assay was less than 0.45％.Based on clinical performance,when the quanti-ty of template was greater than or equal to 100 copies,the agreements between the duplex real-time PCR assay and the conventional PCR assay were 94.3％(GyVg1)and 100％(GyH1).In con-clusion,the newly developed duplex real-time PCR assays exhibited good specificity,sensitivity and repeatability,which could contribute to the rapid detection and differentiation of GyVg1 and GyH1.

To establish a double fluorescent RT-LAMP that can distinguish between chicken astro-virus(CAstV)and avian nephritis virus(ANV),two sets of specific primers and probes labeled with fluorescent groups were designed by comparing the conserved sequences of CAstV ORF1b gene and ANV ORF1b gene downloaded from GenBank.The CAstV probe was labeled with CY3 fluorophore at the 3'end and the quencher BHQ2 at the 5'end.The ANV probe was labeled with CY3 fluorophore at the 3'end and the quencher BHQ2 at the 5'end.The reaction system of the method was optimized,and specificity,repeatability,interference,sensitivity,and clinical sample detection were performed.The results were compared with RT-qPCR and RT-PCR to verify the ef-fectiveness of the method.The experimental results showed that the established double fluorescence RT-LAMP method could complete the reaction within 60 min,and the optimal reac-tion temperature was 65 ℃.This method only detects ANV and CAstV,with no cross-reactivity to other common avian pathogens.The minimum detection limit of CAstV was 1.4 ×10 2 copies/μL,and the minimum detection limit of ANV was 1.5×10 2 copies/μL.The interference and reproduc-ibility tests were good.Compared with RT-qPCR,the coincidence rates of CAstV and ANV were 97.97％and 98.85％,respectively.In conclusion,the double fluorescence RT-LAMP method estab-lished in this study has the characteristics of rapidity,accuracy,good specificity,high sensitivity and good reproducibility,which is suitable for clinical diagnosis and provides technical support for the epidemiological investigation of CAstV and ANV.

Gyrovirus galga1(GyVg1)and gyrovirus homsa1(GyH1)are two newly discovered cir-coviruses that can cause symptoms related to transmissible viral proventriculitis of chickens.These viruses have been reported in various regions worldwide.This research aims to establish a duplex real-time PCR assay capable of identifying and detecting GyVg1 and GyH1.Specific primers and probes were designed based on the conserved regions of GyVg1 and GyH1 respectively using all genome sequence data currently available in GenBank.After optimizing reaction conditions,the du-plex real-time PCR detection method was established and further validated by comparing it with a conventional PCR assay and sequencing results from an analysis of 256 clinical samples collected in 2023 across eight regions of Nanning,Guangxi.The results showed that GyVg1 and GyH1 could be identified in 1 h by the duplex real-time PCR assay and two pairs of primer probes can amplify effectively but there is no any cross reaction with other pathogens.Besides,the detection limit was determined to be 7.5 copies/μL.The correlation coefficient of standard curves exceeded 0.99,and CV for intra-and inter-assay was less than 0.45％.Based on clinical performance,when the quanti-ty of template was greater than or equal to 100 copies,the agreements between the duplex real-time PCR assay and the conventional PCR assay were 94.3％(GyVg1)and 100％(GyH1).In con-clusion,the newly developed duplex real-time PCR assays exhibited good specificity,sensitivity and repeatability,which could contribute to the rapid detection and differentiation of GyVg1 and GyH1.

To establish a double fluorescent RT-LAMP that can distinguish between chicken astro-virus(CAstV)and avian nephritis virus(ANV),two sets of specific primers and probes labeled with fluorescent groups were designed by comparing the conserved sequences of CAstV ORF1b gene and ANV ORF1b gene downloaded from GenBank.The CAstV probe was labeled with CY3 fluorophore at the 3'end and the quencher BHQ2 at the 5'end.The ANV probe was labeled with CY3 fluorophore at the 3'end and the quencher BHQ2 at the 5'end.The reaction system of the method was optimized,and specificity,repeatability,interference,sensitivity,and clinical sample detection were performed.The results were compared with RT-qPCR and RT-PCR to verify the ef-fectiveness of the method.The experimental results showed that the established double fluorescence RT-LAMP method could complete the reaction within 60 min,and the optimal reac-tion temperature was 65 ℃.This method only detects ANV and CAstV,with no cross-reactivity to other common avian pathogens.The minimum detection limit of CAstV was 1.4 ×10 2 copies/μL,and the minimum detection limit of ANV was 1.5×10 2 copies/μL.The interference and reproduc-ibility tests were good.Compared with RT-qPCR,the coincidence rates of CAstV and ANV were 97.97％and 98.85％,respectively.In conclusion,the double fluorescence RT-LAMP method estab-lished in this study has the characteristics of rapidity,accuracy,good specificity,high sensitivity and good reproducibility,which is suitable for clinical diagnosis and provides technical support for the epidemiological investigation of CAstV and ANV.

The aim of this study is to investigate the immune effect of H9 subtype avian influenza virus(AIV)NP protein on mice and lay the foundation for the development of avian influenza vi-rus(AIV)vaccine.The H9N2 virus NP gene amplification product was cloned into the pET-32a expression vector,and the protein expression was verified by SDS-PAGE and Western blot,and the immune effect was evaluated by measuring the secretion of supernatant multicytokines in mouse splenocytes culture.The results showed that the total length of the coding region sequence of NP gene was 1 497 bp,NP recombinant proteins exist in both soluble and insoluble protein forms,and the specific bands were visible in Western blot.After immunizing mice,serum produces IgG-bind-ing antibodies with antibody titers of 1∶40 000.Compared with the control group,IL-2,IL-5 and IL-13 were significantly increased(P＜0.001),and the secretion of IL-6 was significantly increased compared with the control group.IL-4 and IL-12 p70 secretions were elevated compared with con-trols,but there was no significant difference.Compared with the control group,the secretions of IL-1β,IL-18,GM-CMF,TNF-α and IFN-γ were inhibited,but the difference was not significant(P＞0.05).The results showed that NP recombinant protein is a good immunogen,laying a foundation for in-depth research on influenza vaccine.

In order to prepare monoclonal antibody to σ A protein of avian reovirus(ARV)and es-tablish a sandwich ELISA method for the detection of ARV pathogens.In this study,the σ A pro-tein of ARV was expressed as antigen by prokaryotic expression and used to immunize BALB/c mice.Then,stable hybridoma cell lines were screened,and monoclonal antibodies were prepared.A sandwich ELISA detection method based on monoclonal antibody of σA protein was established,and the sensitivity,specificity,repeatability,and accuracy were tested.The results showed that the recombinant plasmid pET-32a-σA was successfully constructed and well expressed in Escherichia coli.After immunizing mice,two hybridoma cell lines 6B3 and 8E11,which could secrete mono-clonal antibodies stably,were successfully prepared.Both monoclonal antibodies could react with natural ARV.One of the monoclonal antibodies secreted by 6B3 was selected as the capture anti-body and the ARV-positive chicken polyclonal antibody was used as the detection antibody.A sand-wich ELISA method was established to detect ARV by optimizing the reaction conditions.The specific test showed that the method only detected ARV pathogens and no other common chicken viral pathogens were detected.The detection limit was 7.72 X 102 EID50/mL of ARV antigen.The coefficient of variation of the intra-and inter-assay tests were less than 5.0％and the reproducibili-ty was good.Thirty samples were tested simultaneously by σA-sandwich ELISA and PCR,and the results were consistent with each other.In conclusion,a sandwich ELISA method based on the monoclonal antibody of σA protein was successfully established for the identification and detection of ARV,which provided a technical means for the accurate and rapid detection of ARV.

Background: Chicken anemia virus (CAV) causes chicken infectious anemia, which results in immunosuppression; the virus has spread widely in chicken flocks in China. Objectives: The aim of this study was to understand recent CAV genetic evolution in chicken flocks in Guangxi Province, southern China. Methods: In total, 350 liver samples were collected from eight commercial broiler chicken farms in Guangxi Province in southern China from 2018 to 2020. CAV was detected by conventional PCR, and twenty CAV complete genomes were amplified and used for the phylogenetic analysis and recombination analysis. Results: The overall CAV-positive rate was 17.1%. The genetic analysis revealed that 84 CAVs were distributed in groups A, B, C (subgroups C1-C3) and D. In total, 30 of 47 Chinese CAV sequences from 2005-2020 belong to subgroup C3, including 15 CAVs from this study. There were some specific mutation sites among the intergenotypes in the VP1 protein. The amino acids at position 394Q in the VP1 protein of 20 CAV strains were consistent with the characteristics of a highly pathogenic strain. GX1904B was a putative recombinant. Conclusions Subgroup C3 was the dominant genotype in Guangxi Province from 2018–2020.The 20 CAV strains in this study might be virulent according to the amino acid residue analysis. These data help improve our understanding of the epidemiological trends of CAV in southern China.

AIM:To explore a more accurate and reliable pathological model of the chronic bronchitis , which has improved from the former single-factor modeling method of the disease .METHODS:The mice in complex group were treated with lipopolysaccharide ( LPS) by tracheal injection on the 1st day and nasal drops on the 14th day, and from the 2nd day to 30th day, the animals were given passive smoking and sulfur dioxide ( SO2 ) inhalation ( except on the 14th day).The mice in SO2 group were exposed to SO2 2 min per day, while in smoking group, the mice were exposed to smoke for about 1 h per day (4 cigarettes each time until one pack of cigarettes were burning up ).In LPS group, the mice had tracheal injection of LPS on the 1st day and nasal drops of LPS on the 14th day and 30th day.Every modeling process las-ted for 30 days.After modeling, the improvement of chronic bronchitis model was evaluated by testing the general condi-tions of the mice , analyzing leukocyte count in bronchoalveolar lavage fluid ( BALF ) , and observing the morphological changes of the bronchial and lung tissues .RESULTS:After modeling, the mice in every model group experienced symp-toms including wet nose, cough, dry and lusterless hair, arched back and curled-up body, showing inactive, and slow down in response .The mice in complex group gained the lowest weight compared to other groups .From each model group , the inflammatory cells infiltrated evidently around the bronchial walls , especially in the bronchial cavity , and the mucilage secretion in the airway increased .The total number of leukocytes in BALF increased significantly in complex group .The in-flammatory cell count in the lung tissue indicated that the mice in complex group had significantly higher levels of inflamma -tory cell infiltration.Besides, the comparison between smoke group and LPS group was statistically significant .CONCLU-SION:Smoking, SO2 inhalation and LPS injection induce bronchial lung disease in mice , and the complex chronic bron-chitis mouse model is a better model with the pathological changes of bronchus , lung tissue and BALF , and pathogenesis of chronic bronchitis .

A novel H17N10 subtype of the influenza A viruses was found in bats in 2012. Protein sequence and structural analyses revealed that the HA17 and NA10 proteins of this strain are different from corresponding ones in known influenza A subtype viruses. Both HA17 and NA10 proteins cannot bind to sialic acid,which indicates that they may have novel functions. This article briefly describes the state of current research into the H17N10 subtype of bat influenza A virus.
Animals ; Chiroptera ; virology ; Influenza A virus ; classification ; genetics ; isolation & purification ; metabolism ; Orthomyxoviridae Infections ; veterinary ; virology ; Viral Proteins ; genetics ; metabolism

In this report, the immunopharmacological effects of Polyactin A ( PAA ) were presented. When the SRBC immunized mice were administered daily 2. 5~40mg/kg ( ip ) of PAA for 3 or 5 days, the serum level of hemolysin, the antibody production in spleen and the number of nucleated cells of spleen were enhanced significantly; and the efficacy-dose dependency was evident in these experiments。 In spite of these effects, PAA didn't affect the kinetics of circulating antibody level.In other experiments, it was found that the efficiency was more potent when PAA was given before or simultaneously with SRBC immunization than given after.