[Objective]The aim of this study is to explore the dynamic changes of Porcine circovirus type 2 (PCV2) and the propagation differences between different PCV2 strains.[Method]A rapid, sensitive and SYBR Green I-based r...[Objective]The aim of this study is to explore the dynamic changes of Porcine circovirus type 2 (PCV2) and the propagation differences between different PCV2 strains.[Method]A rapid, sensitive and SYBR Green I-based real-time quantitative PCR assay was developed to detect PCV2 in mice. The Balb/c mice were inoculated with 200 μL of 1×10^6 TCID 50 /mL different strains of PCV2;the serum and tissues of mice were collected at different time. SYBR Green I fluorescent quantitative PCR was used to determine the viral titer in the serum and tissues of mice.[Result]The results indicated that the SYBR Green I PCR could speci fically detect PCV2 with high specificity. All strains were detected in the serum 14 d after infection, and 2007HA strain had the highest level of 1.21×10^8 copies/mL. The titers of all strains decreased 21 d after infection and then increased 28 d after infection. In addition, 2010NJ strain had the highest titer in serum 28 d after infection. The two PCV2b isolates, 2010NJ and 2009ZJ, had the highest titer in lungs and spleens. [Conclusion]All results showed that different PCV2 isolates have different proliferation ef ficiencies in Balb/c mice, even if they belong to the same subtype. In addition, the proliferation rate of 2009ZJ in visceral organs was significantly higher than that in serum. However, this phenomenon is not obvious for other strains. These results laid a foundation for the analysis of proliferation characteristics and pathogenicity of different PCV2 strains in vivo.展开更多
文摘[Objective]The aim of this study is to explore the dynamic changes of Porcine circovirus type 2 (PCV2) and the propagation differences between different PCV2 strains.[Method]A rapid, sensitive and SYBR Green I-based real-time quantitative PCR assay was developed to detect PCV2 in mice. The Balb/c mice were inoculated with 200 μL of 1×10^6 TCID 50 /mL different strains of PCV2;the serum and tissues of mice were collected at different time. SYBR Green I fluorescent quantitative PCR was used to determine the viral titer in the serum and tissues of mice.[Result]The results indicated that the SYBR Green I PCR could speci fically detect PCV2 with high specificity. All strains were detected in the serum 14 d after infection, and 2007HA strain had the highest level of 1.21×10^8 copies/mL. The titers of all strains decreased 21 d after infection and then increased 28 d after infection. In addition, 2010NJ strain had the highest titer in serum 28 d after infection. The two PCV2b isolates, 2010NJ and 2009ZJ, had the highest titer in lungs and spleens. [Conclusion]All results showed that different PCV2 isolates have different proliferation ef ficiencies in Balb/c mice, even if they belong to the same subtype. In addition, the proliferation rate of 2009ZJ in visceral organs was significantly higher than that in serum. However, this phenomenon is not obvious for other strains. These results laid a foundation for the analysis of proliferation characteristics and pathogenicity of different PCV2 strains in vivo.