Viral encephalopathy and retinopathy of Dicentrarchus labrax and Sparus aurata farmed in Tunisia.

Nadia Chérif , Richard Thiéry (1) , Jeannette Castric (2) , Stephane Biacchesi , Michel Brémont , Fatma Thabti , Latifa Limem , Salah Hammami

1 LERPRA - Laboratoire d'études et de recherches sur les petits ruminants et les abeilles
2 Laboratoire d'études et de recherches avicoles, porcines et piscicoles

Viruses belonging to the Nodaviridae family cause disease worldwide among a large number of species of marine fish, and have been described in all continents. In the present study, a total of 69 farmed Tunisian sea bass (Dicentrarchus labrax) and 24 sea bream (Sparus aurata) samples were tested monthly for the detection of betanodavirus. The virus was identified in both species using indirect immunofluorescence assays (IFAT) and RT-PCR. In addition sequence analysis of part of the coat protein gene indicated that both species were infected by highly related, but distinct, strains belonging to the RGNNV genotype. The sequence of the coat protein gene of several strains was identical but up to 9 different sequences were detected in a single farm. In addition, viral sequences obtained from fish that were held at lower temperature (<20 degrees C) were distinct from the rest of the sequences.

Keywords: betanodavirus; VNN; nodavirus

Domains: Virology

Nadia Chérif, Richard Thiéry, Jeannette Castric, Stephane Biacchesi, Michel Brémont, et al.. Viral encephalopathy and retinopathy of Dicentrarchus labrax and Sparus aurata farmed in Tunisia.. Veterinary Research Communications, 2009, 33 (4), pp.345-53. ⟨10.1007/s11259-008-9182-3⟩. ⟨hal-00403240⟩