Genetic typing of equine arteritis virus isolates from Argentina

Abstract

We report the nucleotide sequence and genetic diversity of four Equine Arteritis Virus (EAV) ORF 5 and 6 from Argentina isolates, obtained from asymptomatic virus-shedding stallions. Nucleic acid recovered from the isolates were amplified by RT-PCR and sequenced. Nucleotide and deduced amino acid sequences from the Argentine isolates were compared with 17 sequences available from the GenBank. Phylogenetic analysis revealed that the Argentine isolates grouped together in a definite cluster near European strains. Despite the greater genetic variability among ORF 5 from different isolates and strains of EAV, phylogenetic trees based on ORF 5 and 6 are similar. Both trees showed that virus sequences from America and Europe segregate into distinct clades based on sequence analysis of either ORF 5 or 6. This study constitutes the first characterization of Argentine EAV isolates.

The equine arteritis virus isolate from the 2010 Argentinian outbreak

“…The phylogenetic dataset was built with five strains isolated in Argentina, sequences reported previously (3,4,5,6,11), and a group of selected sequences obtained from GenBank (Table I). Sequences were edited using BioEdit software version 5 (19) and aligned in molecular evolutionary genetic analysis (MEGA) software, version 4.0, using the ClustalW algorithm.…”

“…In 1998, several EAV antibody-positive animals were detected in two sporthorse breeding farms that practised artificial insemination with imported semen. A follow-up study between July 2001 and December 2003 found a prevalence of 45.8% in one of those farms; three stallions were virus isolation-positive (strains LP02/R, LP02/C, LP02/P) (5). Three new sequences of EAV from three archive semen samples were obtained in 2008: one (RO-LP-ARG) from a stallion housed on the breeding farm where the first strain of EAV was isolated and the other two (RZ-LP-ARG, KB-LP-ARG) from the farm where the LP02 strains had been isolated (6).…”

Extended Phylogeny of the Equine Arteritis Virus Sequences Including South American Sequences

“…The isolates of EAV in our country were carried out in 2001, 2002 and 2007 from seropositive imported stallions located in three farms with high seroprevalence of EAV. Based on the partial sequences of ORF5, the Argentinean EAV strains and sequences are grouped with the European EAV strains [10][11][12][13] .…”

“…These three strains were obtained from three Warmblood stallions (registered as Zangersheide branded). At the time of the study, this farm, which also breeds and trains jumping horses, had approximately 280 horses, including stallions, mares, donor mares and foals (Farm B) [11] . Circumstantial evidence suggested that the EAV dissemination inside the farm was initiated by one of these three stallions imported to this farm from Europe in 2001.…”

“…Circumstantial evidence suggested that the EAV dissemination inside the farm was initiated by one of these three stallions imported to this farm from Europe in 2001. These animals had no evidence of clinical disease but soon after the new stallions arrived, other stallions, mares and foals on the farm became seropositive to EAV with an estimated prevalence of 45% [11,12] . At that moment, the animal health control authorities closed both farms in order to stop the spreading of the virus caused by the trade of horses.…”