Detection of Maedi-Visna virus from sheep bronchoalveolar lavage by Nested PCR evaluation of different primers pairs / Detecção do vírus Maedi-Visna em amostras de lavado bronco-alveolar de ovinos através da técnica de Nested PCR utilizando diferentes pares de primers

ABSTRACT

Background: Small ruminant lentiviruses (SRLV) are characterized by a high degree of genetic variability related to your replication process, resulting in several strains in different geographic regions. The Polymerase Chain Reaction (PCR) is very successful in the detection of proviral DNA of SRLV, however, due to the high variability of the lentivirus genome, the efficiency and sensibility of PCR depends mainly on the specificity of the primers designed and the choice of the amplified target viral region. The aim of this study was to compare detection of Maedi Visna Virus (MVV) from bronco alveolar lavage samples of sheep by Nested PCR using primers for the gag and LTR genes. Materials, Methods & Results: Samples of sheep bronchoalveolar lavage (n = 58) from slaughterhouse in the Metropolitan Region of Fortaleza were previously tested by nested PCR using primers for region gag. Thereafter, these samples were tested by nested PCR with primers designed for the LTR region. Both tests were conducted using thermocycler (Biocycler®) under the following conditions initial denaturation at 94C for 5 min, followed by 35 cycles of denaturation at 94C for 1 min, annealing of primers at 56C for 1 min and extension of DNA at 72C for 45 s with a final extension at 72 for 7 min. The first and second round were performed under the same conditions. Every amplification was performed [...]