A total 91 serum samples and 51 pig tissue samples were collected between October 2009 and June 2010 from 30 herds, where a clinical picture of diseased or/and porcine reproductive and respiratory syndrome (PRRS) antibody-positive pigs were detected. From the 142 samples tested, 65 (45.8%) were identified as porcine reproductive and respiratory syndrome virus (PRRSV) positive by one-step reverse transcription and polymerase chain reaction (RT-PCR). The sequencing results of PRRSV detected in 30 positive herds revealed the detection of six distant viruses of PRRS, one lineage of PRRSV was detected in 76,6% of infected herds. The results of this study demonstrated that infection with uncommon PRRSV strains occurred in Slovenian pig farms, which suggests the problems in diagnosis and control of EU PRRSV.
COBISS.SI-ID: 3477370
Natural exposure is with acceptance of biosecurity rules and improvement of management are key factors in elimination and eradication of PRRS. All above mentioned measures are necessary for successful pig production not considering health status of the herd. Serumization and vaccination are at the moment methods with limited success.
COBISS.SI-ID: 3555962
The purpose of this study was to determine the sensitivity of conventional RT-PCR protocol and five commercial real-time kits used for the detection of porcine reproductive and respiratory syndrome virus (PRRSV). 218 field samples were collected between 2009 and 2011 from 50 PRRSV positive and 45 negative pig herds from Slovenia. According to determined 258 nucleotides long sequences (ORF7) 12 different lineages of Type I - subtype 1 (a=1, b=9, c=1, d=1, e=85, f=10, g=2, h=4, i=3, j=3, k=1, m=8) with 85.7-93.8 % nucleotide identity between lineages and four samples belong to Type II were identified. The highest sensitivity was observed with kit E (96,3%) and with kit B (94,5%), followed by conventional RT-PCR (87,8%) and kit D (82,1%), while the lowest sensitivity was observed with kit A (55,3%) and kit C (53,8%). Reduced sensitivity was directly related to the some genetic lineages and RNA copy number in a sample. These findings emphasize that diagnostic PCR kits (conventional and real-time) have to continuously follow the genetic evaluation of the PRRSV subtype viruses especially Type I and regularly update their primer and probes sequences.
COBISS.SI-ID: 3592058