Genotyping and Classification of Tunisian Strains of Avian Reovirus using RT-PCR and RFLP Analysis.

Since 1998, avian reovirus (ARV) infection has been detected in broiler and breeding chicken flocks in Tunisia. The genotype of avian reoviruses was established using simple and rapid approaches. Reverse transcription PCR (RT-PCR) on both sigma C (σC) and sigma B (σB)-encoding genes followed by restriction fragment length polymorphism (RFLP) analyses were used to better characterize Tunisian isolated strains.

Risk factors and characteristics of low pathogenic avian influenza virus isolated from commercial poultry in Tunisia.

Objective: Estimate the seroprevalence of influenza A virus in various commercial poultry farms and evaluate specific risk factors as well as analyze their genetic nature using molecular assays.

Materials And Methods: This report summarizes the findings of a national survey realized from October 2010 to May 2011 on 800 flocks in 20 governorates. Serum samples were screened for the presence of specific influenza virus antibodies using cELISA test.

Molecular characterization of avian reovirus isolates in Tunisia.

Background: Genotype analyses of avian reoviruses isolated from organ samples collected from chickens with suspicious clinical symptoms, between 1997-2008, was based on sequences for both σC and σB genes and aligned with those published in the Genbank, making it possible to carry out studies of molecular classification and relationships.

Methods: The full length of the known variable protein σC and part of the σB encoding genes, were amplified with RT-PCR, using conserved primers. PCR products were sequenced and the sequences were analyzed and aligned with avian reovirus sequences from the Genbank database.

Characterization of new variants of avian infectious bronchitis virus in Tunisia.

Three infectious bronchitis virus (IBV) strains, isolated from suspected Tunisian broiler flocks, were characterized as variant viruses using genotyping and serotyping techniques. They were compared with commonly used vaccine strains, including 793/B, D274, and Massachusetts types. Reverse transcription-PCR-restriction fragment length polymorphism, nucleotide sequencing, and GenBank BLAST database analyses of the hypervariable region of the S1 subunit of the virus spike gene showed that the three isolates, designated TN20/00, TN200/01, and TN335/01, share from 64% to 82% homologies between each other but are very different from the H120 strain, the only infectious bronchitis vaccine used in Tunisia.