TDK conference 2010

Circoviruses are DNA viruses with small, single stranded circular genom. To our actual knowledge swine is the only mammalian species to possess its own circovirus (porcine circovirus, PCV). According to differences in pathogenicity and nucleic acid sequence PCV strains can be divided into two groups: PCV1 (non-pathogenic) and PCV2 (pathogenic). Both can be present in domestic pigs and wild boars and it is also known that in laboratories mice can be experimentally infected with PCV2, the virus replicates in them and is excreted as well. The presence of PCV in mammalian species other than swine is controversial, other mammalian circovirus is unknown. The aim of our investigations was to detect porcine circovirus in rodents under field conditions, and to prove or rule out their epidemiological significance.

For our examinations we collected rodents (mice and rats) and PCV2-positive swine organ samples from swine herds infected by circovirus, but we’ve also studied the presence of the virus in rodents living outside pig farms. Using standard methods we gained nucleic acid from organ samples of swines and rodents, and amplified the DNA with universal or PCV2 specific primer pairs by polymerase chain reaction, and then we sequenced the amplicons.

PCV DNA was detectable from 65,5 % of mice and 23,8 % of rats living with the pig herds, and from 80,0 % of the swine samples. In rodents having no connection with herds we couldn’t identify PCV. Sequence analysis of the PCR products showed that all of them belonged into the PCV2 genotype, with no exception, identification of rodent specific circoviruses was not successful.