猪繁殖与呼吸综合征病毒基因2型类NADC30毒株感染模型的建立OA北大核心CSTPCD

The aim of this study was to establish an infection model for PRRSV new emerging NADC30-like strain to lay the foundation for vaccine and therapeutic drug screening.The PRRSV/GSWW/2018 strain is a NADC30-like virus strain isolated from one pig farm in Gansu province,which was selected as challenge virus strain to develop infection model.Total of 12 pigs was evenly separated into 4 groups,which were infected by nasal inhalation,intramuscular and subcutaneous injections of 2 mLcell cultured virus materials(contain 106TCID50/mL of the virus)with one group as normal control.Blood,nasalswabs and anal swabs were collected to detect viraemia and virus excretion.Body temperature and weight changes were detected every day,and pigs were anatomized after death to check lung lesions and virus persistence in different lymph nodes.The successfulness of the infection model was evaluated based on the above indexes.The results showed that pigs infected by the nasal and intramuscular routes began to have a fever at 24 hours post infection,which lasted for about 1 week;the viraemia peaked at 48 hours post infection and lasted until the death;all diseased pigs showed decreased body weight and typical PRRS clinical signs,and gradually died at 12 to 14th days post infection for the nasally and intramuscularly challenge groups.All pigs keep healthy state until the end of the experiment for the subcutaneous inoculated group and the uninfected control group.In conclusion,the PRRSV/GSWW/2018 strain could be lethal to piglets after challenge by intramuscular or nasal routes,and all pigs showed typical clinical symptoms and died within two weeks after virus challenge.The establishment of this challenge model for NADC30 like PRRSV strain laid a good foundation for the subsequent screening of antiviral drugs or vaccine development.