Study On The SYBR Green ⅠFluorescence Quantitative PCR Detection Method Of Several Common Viral Mixed Infections Of Pigs

Hog cholera virus(HCV), Porcine reproductive and respiratory syndrome virus(PRRSV), Porcine pseudorabies (PRV) and Porcine circovirus type 2 (PCV-2) are 4 major etiological agents of reproductive failure in swine. HCV infections in pigs may cause a highly contagious disease, of which the main characteristics is bleeding and hemorrhagic, and it caused abortion of pregnant sows, fetal aberration, chronic nutritional consumption, immune system injury such as reduction of lymphocytes and thrombocytopenia. Porcine reproductive and respiratory syndrome (PRRS) is characterized by severe reproductive failure in sows including 1ast-term abortions, dead, weak and mummified piglets, respiratory disease and increased mortality for pre-weaning pigs. PRV manifested as fever, encephalomyelitis and other neurological symtoms in a variety of livestock and wild animals and embryoic resorption, fetal mummification, abortion and stillbirths in sow. PCV-2 was considered being associated with Postweaning Multisystemic Wasting Syndrome (PMWS) in piglet, reproductive failure, dermatitis and enteritis in sow. Swine influenza is significant in public health like avian influenza. In 2009, SIV which caused hundreds of people death spreaded all over the word in a short time, so control and prevention of this desease is important task .Conventional virus isolation and serogical method are time consuming and are comparatively low in sensitivity, which can not detect exactly and latency infection. Althought, there have been report that TaqMan-based real-time quantitative PCR for detection of these virus. But this mothed is expersive cost, and need especial probe and mixed infection is more epidemic nowdays. Therefor, quantitive real-time PCR with a quick, cheap, sensitive, and specific test for these virus needs more work.(1) A multiplex polymerase chain reaction (PCR) was designed for the simultaneous detection of three viruses involved in reproductive failure in pigs: Hog cholera virus(CSFV), porcine pseudorabies virus (PRV), porcine circovirus type 2 (PCV-2). Each of the three pairs of oligonucleotide primers exclusively amplified the targeted fragment of the specific viruses. The sensitiviy of the multiplex PCR using purified plasmid constructs containing the specific viral target fragments was183, 231, 203 copies for CSFV, PRV, and PCV-2, respectively. When the specificity of the assay using specific CSFV, PRV and PCV-2 primers was evaluated by testing the other porcine viruses, no cross-reactions were detected with non- SIV, PPV and PRRSV. This method is a rapid, sensitive and cost-effective diagnostic tool for the routine surveillance of viral infections in pigs.(2) A multiplex polymerase chain reaction (PCR) was designed for the simultaneous detection of three viruses involved in reproductive failure in pigs: Hog cholera virus(CSFV), Porcine reproductive and respiratory syndrome virus(PRRSV), porcine circovirus type 2 (PCV-2). Each of the three pairs of oligonucleotide primers exclusively amplified the targeted fragment of the specific viruses. The sensitiviy of the multiplex PCR using purified plasmid constructs containing the specific viral target fragments was 177, 202, 181 copies for CSFV, PRRSV, and PCV-2, respectively. When the specificity of the assay using specific CSFV, PRRSV and PCV-2 primers was evaluated by testing the other porcine viruses, no cross-reactions were detected with non-PPV, PRV and SIV. This method is a rapid, sensitive and cost-effective diagnostic tool for the routine surveillance of viral infections in pigs.(3) A multiplex polymerase chain reaction (PCR) was designed for the simultaneous detection of three viruses involved in reproductive failure in pigs: Hog cholera virus(CSFV), Porcine reproductive and respiratory syndrome virus(PRRSV), porcine circovirus type 2 (PCV-2), Swine influenza virus(SIV). Each of the three pairs of oligonucleotide primers exclusively amplified the targeted fragment of the specific viruses. The sensitiviy of the multiplex PCR using purified plasmid constructs containing the specific viral target fragments was 173, 196, 203,211 copies for CSFV, PRRSV, PCV-2 and SIV, respectively. When the specificity of the assay using specific PPV, PRV and PCV-2 primers was evaluated by testing the other porcine viruses, no cross-reactions were detected with non-PPVand PRV. This method is a rapid, sensitive and cost-effective diagnostic tool for the routine surveillance of viral infections in pigs.