In this study, RT-PCR was performed on lung tissue samples from sick pigs in a suspected outbreak of porcine reproductive and respiratory syndrome (PRRS) at a pig farm in Mianyang City, Sichuan Province, China. Positi...In this study, RT-PCR was performed on lung tissue samples from sick pigs in a suspected outbreak of porcine reproductive and respiratory syndrome (PRRS) at a pig farm in Mianyang City, Sichuan Province, China. Positive samples were inoculated into Marc-145 cells to observe lesions. The Marc-145 cells with cytopathic lesions were identified by indirect immunofluorescence. The whole genome sequences of the isolated and purified strains were amplified by RT-PCR and analyzed for homology and genetic evolution. A strain of porcine reproductive and respiratory syndrome virus (PRRSV), named SCMY2023 (GenBank No. PQ179742), was successfully isolated. SCMY2023 has a genome length of 15,321 base pairs (without a poly A tail). Nucleotide and amino acid homology analyses suggest that this strain belongs to Lineage 8, a variant of the highly pathogenic porcine reproductive and respiratory syndrome virus (HP-PRRSV) prevalent in China. Recombination and genetic evolution analyses indicate that this isolate is a PRRSV variant that recombined with HuN-ZZ (Lineage 8, 98.79% homology) on the backbone of the SCSN2020 strain (Lineage 8, 99.35% homology) in the recombination region from 4407 to 13,107 nucleotides (ORF1a to ORF3). In-depth study of the genetic recombination of this isolate can provide a reference for the prevention and control of PRRS.展开更多
The rapid expansion of large-scale pig farming has brought about a surge in viral diseases with high morbidity rates and diverse manifestations.This widespread occurrence of multiple viral diseases in pig farms has in...The rapid expansion of large-scale pig farming has brought about a surge in viral diseases with high morbidity rates and diverse manifestations.This widespread occurrence of multiple viral diseases in pig farms has inflicted severe economic losses on the global swine industry.Consequently,there is an urgent need for eco-friendly and efficient antivi-ral drugs that can effectively combat viruses and prevent diseases such as PEDV,PRRSV,PRV,and other viral infections.To this end,we conducted a study on the antiviral activity and cytotoxicity of eleven different Chinese herbal extracts(CHE) against PRV.In vitro testing of several extracts,namely,Echinacea,Ilex purpurea Hassk,Ganoderma lucidum Kars,Taraxacum mongolicum,and Ilex rotunda Thunb,exhibited remarkable inhibition of PRV infection without causing any cytotoxic effects.Specifically,their antiviral selectivity indexes were significantly higher,with values ranging from 6-to 144-fold.The antiviral efficacy of five CHEs was evaluated against other RNA viruses,including PRRSV and PEDV.The extracts showed substantial inhibition of PEDV and PRRSV proliferation.Echinacea and Ilex purpurea Hassk extracts exhibited the highest virus inhibitory effects.To understand the antiviral mechanisms underlying their potent activity,a time-of-addition experiment was conducted.The results indicated that these extracts effectively targeted the early infection and postinfection stages of PRV,PEDV,and PRRSV.The study found that the Chinese herbal extracts,Echinacea and Ilex purpurea Hassk,had both direct and indirect effects on virus particles and cellular targets,demonstrating broad-spectrum antiviral activity against multiple clinical strains of PRV and PEDV.These findings provide a strong foundation for the development of herbal medicines to prevent and treat infections caused by PRV,PEDV and PRRSV in the swine industry.The identified extracts show great promise for the formulation of effective and environmentally friendly antiviral interventions.展开更多
文摘In this study, RT-PCR was performed on lung tissue samples from sick pigs in a suspected outbreak of porcine reproductive and respiratory syndrome (PRRS) at a pig farm in Mianyang City, Sichuan Province, China. Positive samples were inoculated into Marc-145 cells to observe lesions. The Marc-145 cells with cytopathic lesions were identified by indirect immunofluorescence. The whole genome sequences of the isolated and purified strains were amplified by RT-PCR and analyzed for homology and genetic evolution. A strain of porcine reproductive and respiratory syndrome virus (PRRSV), named SCMY2023 (GenBank No. PQ179742), was successfully isolated. SCMY2023 has a genome length of 15,321 base pairs (without a poly A tail). Nucleotide and amino acid homology analyses suggest that this strain belongs to Lineage 8, a variant of the highly pathogenic porcine reproductive and respiratory syndrome virus (HP-PRRSV) prevalent in China. Recombination and genetic evolution analyses indicate that this isolate is a PRRSV variant that recombined with HuN-ZZ (Lineage 8, 98.79% homology) on the backbone of the SCSN2020 strain (Lineage 8, 99.35% homology) in the recombination region from 4407 to 13,107 nucleotides (ORF1a to ORF3). In-depth study of the genetic recombination of this isolate can provide a reference for the prevention and control of PRRS.
基金supported by the Hubei Agricultural Research System (HBHZDZB-2020-005)the National Natural Science Foundation of China (31872328,32272990)+2 种基金the National Key Research and Development Program of China(2021YFD1800101-2)the Science and Technology Project of Guizhou Province([2020]4Y217)the "Yingzi Tech&Huazhong Agricultural University Intelligent Research Institute of Food Health"(No.IRIFH202209)。
文摘The rapid expansion of large-scale pig farming has brought about a surge in viral diseases with high morbidity rates and diverse manifestations.This widespread occurrence of multiple viral diseases in pig farms has inflicted severe economic losses on the global swine industry.Consequently,there is an urgent need for eco-friendly and efficient antivi-ral drugs that can effectively combat viruses and prevent diseases such as PEDV,PRRSV,PRV,and other viral infections.To this end,we conducted a study on the antiviral activity and cytotoxicity of eleven different Chinese herbal extracts(CHE) against PRV.In vitro testing of several extracts,namely,Echinacea,Ilex purpurea Hassk,Ganoderma lucidum Kars,Taraxacum mongolicum,and Ilex rotunda Thunb,exhibited remarkable inhibition of PRV infection without causing any cytotoxic effects.Specifically,their antiviral selectivity indexes were significantly higher,with values ranging from 6-to 144-fold.The antiviral efficacy of five CHEs was evaluated against other RNA viruses,including PRRSV and PEDV.The extracts showed substantial inhibition of PEDV and PRRSV proliferation.Echinacea and Ilex purpurea Hassk extracts exhibited the highest virus inhibitory effects.To understand the antiviral mechanisms underlying their potent activity,a time-of-addition experiment was conducted.The results indicated that these extracts effectively targeted the early infection and postinfection stages of PRV,PEDV,and PRRSV.The study found that the Chinese herbal extracts,Echinacea and Ilex purpurea Hassk,had both direct and indirect effects on virus particles and cellular targets,demonstrating broad-spectrum antiviral activity against multiple clinical strains of PRV and PEDV.These findings provide a strong foundation for the development of herbal medicines to prevent and treat infections caused by PRV,PEDV and PRRSV in the swine industry.The identified extracts show great promise for the formulation of effective and environmentally friendly antiviral interventions.
