Co-existence of multiple strains of porcine circovirus type 2 in the same pig from China

Virology Journal

Jin-Xue Long²  Wen-Kang Wei¹  Shi-Shan Yuan²  Duo-Liang Ran³  Cheng Yue³  Tao Lin²  Lv Huang²  Jian-Wu Zhang²  Zu-Zhang Wei²  Sheng-Nan Chen³  Shao-Lun Zhai³ 

[1] Institute of Veterinary Medicine, Guangdong Academy of Agricultural Sciences, Guangzhou 510640, China;Department of Swine Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China;College of Veterinary Medicine, Xinjiang Agricultural University, Urumqi 830052, China

关键词: New infection form;    Co-existence;    Multiple viral strains;    Porcine circovirus type 2;   

Others  :  1155618
DOI  :  10.1186/1743-422X-8-517

 received in 2011-08-25, accepted in 2011-11-13,  发布年份 2011

【 摘 要 】

Pigs are often co-infected by different viral strains from the same virus. Up to now, there are few reports about co-existence of different porcine circovirus type 2 (PCV2) strains in China. The aim of this study was to evaluate it in Chinese swine herds. 118 PCV2 positive DNAs isolated from diseased pigs identified by classic PCR were re-detected using a modified differential PCR assay. The results indicated that co-existence rates of PCV2 were 32.2% (38/118) in diseased pigs and 0% (0/41) in asymptomatic pigs. Four PCV2 complete genomes were cloned from two co-infected samples and their nucleotide (nt) identities were 95%-97.3%. The phylogenetic analysis showed that four PCV2 strains were divided into different genotypes, PCV2a, PCV2b, PCV2d and PCV2e, respectively. In addition, co-existence were not detected in 41 serum samples from healthy pigs but PCV2 single infection (31.7%, 13/41) existed. These data revealed that the co-existence of different strains of PCV2 might contribute to the development of more severe clinical symptoms for pigs. This is the first report confirming the co-existence of different PCV2 strains in Chinese swine herds. Meanwhile, this study could help us to understand new infection and prevalence forms of PCV2 clinically.

【 授权许可】

   
2011 Zhai et al; licensee BioMed Central Ltd.

【 图 表 】

Figure 1.

Figure 2.

【 参考文献 】

• [1]Harding JC, Clark EG, Strokappe JH, Willson PI, Ellis JA: Postweaning multisystemic wasting syndrome: Epidemiology and clinical presentation. J Swine Health Prod 1998, 6:249-254.
• [2]Allan GM, Ellis JA: Porcine circoviruses: a review. J Vet Diag Invest 2000, 12:3-14.
• [3]Harms PA, Halbur PG, Sorden SD: Three cases of porcine respiratory disease complex associated with porcine circovirus type 2 infection. J Swine Health Prod 2002, 10:27-30.
• [4]Kim J, Chung HK, Chae C: Association of porcine circovirus 2 with porcine respiratory disease complex. Vet J 2003, 166:251-256.
• [5]Chae C: A review of porcine circovirus 2-associated syndromes and diseases. Vet J 2004, 169:326-336.
• [6]Segalés J, Olvera A, Grau-Roma L, Charreyre C, Nauwynck H, Larsen L, Dupont K, McCullough K, Ellis J, Krakowka S, et al.: PCV-2 genotype definition and nomenclature. Vet Rec 2008, 162:867-868.
• [7]Wang F, Guo X, Ge X, Wang Z, Chen Y, Cha Z, Yang H: Genetic variation analysis of Chinese strains of porcine circovirus type 2. Virus Res 2009, 145:151-156.
• [8]Cheung AK: Transcriptional analysis of porcine circovirus. Virology 2003, 305:168-180.
• [9]Nawagitgul P, Morozov I, Bolin SR, Harms PA, Sorden SD, Paul PS: Open reading frame 2 of porcine circovirus type 2 encodes a major capsid protein. J Gen Virol 2000, 81:2281-2287.
• [10]Carman S, McEwen B, DeLay J, van Dreumel T, Lusis P, Cai H, Fairles J: Porcine circovirus-2 associated disease in swine in Ontario (2004 to 2005). Can Vet J 2006, 47:761-762.
• [11]Gagnon CA, Tremblay D, Tijssen P, Venne MH, Houde A, Elahi SM: The emergence of porcine circovirus 2b genotype (PCV-2b) in swine in Canada. Can Vet J 2007, 48:811-819.
• [12]Cheung AK, Lager KM, Kohutyuk OI, Vincent AL, Henry SC, Baker RB, Rowland RR, Dunham AG: Detection of two porcine circovirus type 2 genotypic groups in United States swine herds. Arch Virol 2007, 152:1035-1044.
• [13]Dupont K, Nielsen EO, Baekbo P, Larsen LE: Genomic analysis of PCV2 isolates from Danish archives and a current PMWS case-control study supports a shift in genotypes with time. Vet Microbiol 2008, 128:56-64.
• [14]Hesse R, Kerrigan M, Rowland R: Evidence for recombination between PCV2a and PCV2b in the field. Virus Res 2008, 132:201-207.
• [15]Fenaux M, Halbur PG, Haqshenas G, Royer R, Thomas P, Nawagitgul P, Gill M, Toth TE, Meng XJ: Cloned genomic DNA of type 2 porcine circovirus is infectious when injected directly into the liver and lymph nodes of pigs: characterization of clinical disease, virus distribution, and pathologic lesions. J Virol 2002, 76:541-551.
• [16]Harding JC, Ellis JA, McIntosh KA, Krakowka S: Dual heterologous porcine circovirus genogroup 2a/2b infection induces severe disease in germ-free pigs. Vet Microbiol 2010, 145:209-219.
• [17]Opriessnig T, Ramamoorthy S, Madson DM, Patterson AR, Pal N, Carman S, Meng XJ, Halbur PG: Differences in virulence among porcine circovirus type 2 isolates are unrelated to cluster type 2a or 2b and prior infection provides heterologous protection. J Gen Virol 2008, 89:2482-2491.
• [18]Firth C, Charleston MA, Duffy S, Shapiro B, Holmes EC: Insights into the evolutionary history of an emerging livestock pathogen: porcine circovirus 2. J Virol 2009, 83:12813-12821.
• [19]Cságola A, Kecskeméti S, Kardos G, Kiss I, Tuboly T: Genetic characterization of type 2 porcine circoviruses detected in Hungarian wild boars. Arch Virol 2006, 151:495-507.
• [20]Ma CM, Hon CC, Lam TY, Li VY, Wong CK, de Oliveira T, Leung FC: Evidence for recombination in natural populations of porcine circovirus type 2 in Hong Kong and mainland China. J Gen Virol 2007, 88:1733-1737.
• [21]Olvera A, Cortey M, Segales J: Molecular evolution of porcine circovirus type 2 genomes: phylogeny and clonality. Virology 2007, 357:175-185.
• [22]Cheung AK: Homologous recombination within the capsid gene of porcine circovirus type 2 subgroup viruses via natural co-infection. Arch Virol 2009, 154:531-534.
• [23]Lefebvre DJ, Van Doorsselaere J, Delputte PL, Nauwynck HJ: Recombination of two porcine circovirus type 2 strains. Arch Virol 2009, 154:875-879.
• [24]Niel C, Diniz-Mendes L, Devalle S: Rolling-circle amplification of Torque teno virus (TTV) complete genomes from human and swine sera and identification of a novel swine TTV genogroup. J Gen Virol 2005, 86:1343-1347.
• [25]Dezen D, Rijsewijk FA, Teixeira TF, Holz CL, Cibulski SP, Franco AC, Dellagostin OA, Roehe PM: Multiply-primed rolling-circle amplification (MPRCA) of PCV2 genomes: Applications on detection, sequencing and virus isolation. Res Vet Sci 2010, 88:436-440.