Growth Characteristics of a Highly Virulent, a Moderately Virulent, and an Avirulent Strain of Equine Arteritis Virus in Primary Equine Endothelial Cells Are Predictive of Their Virulence to Horses

AbstractEquine viral arteritis (EVA) is an endotheliotropic viral disease of horses caused by equine arteritis virus (EAV). Although there is only one serotype of EAV, there is marked variation in the virulence of different strains of the virus. The replication and cytopathogenicity of three well-characterized strains of EAV of different virulence to horses were compared in rabbit kidney (RK-13) and primary equine pulmonary artery endothelial cells (ECs). Viral protein expression, plaque size, and cytopathogenicity of all three viruses were similar in RK-13 cells, whereas two virulent strains of EAV were readily distinguished from an avirulent strain by their plaque morphology and cytopathogenicity in primary equine ECs. Furthermore, EAV nucleocapsid protein was detected by flow cytometric analysis significantly later in ECs infected with the avirulent than those infected with the virulent strains of EAV. Primary equine ECs provide a convenient and relevant model for in vitro characterization of the pathogenesis of EVA and the virulence determinants of EAV

Emergence of novel equine arteritis virus (EAV) variants during persistent infection in the stallion: Origin of the 2007 French EAV outbreak was linked to an EAV strain present in the semen of a persistently infected carrier stallion

AbstractDuring the summer of 2007, an outbreak of equine viral arteritis (EVA) occurred in Normandy (France). After investigation, a link was suggested between an EAV carrier stallion (A) and the index premise of the outbreak. The full-length nucleotide sequence analysis of a study reference strain (F27) isolated from the lung of a foal revealed a 12,710 nucleotides EAV genome with unique molecular hallmarks in the 5′UTR leader sequence and the ORF1a sequence encoding the non-structural protein 2. The evolution of the viral population in the persistently infected Stallion A was then studied by cloning ORFs 3 and 5 of the EAV genome from four sequential semen samples which were collected between 2000 and 2007. Molecular analysis of the clones confirmed the likely implication of Stallion A in the origin of this outbreak through the yearly emergence of new variants genetically similar to the F27 strain

First detection of equine coronavirus (ECoV) in Europe

International audienceEquine coronavirus (ECoV) is involved mainly in enteric infections. Following the recent description of ECoV in 2000, this study reports for the first time the presence of ECoV in France and, on a wider scale, in Europe. ECoV was molecularly detected from diarrheic and respiratory specimens. Sequencing and phylogenetic analyses demonstrated that European strains are most closely related to the reference North American strain (ECoV-NC99) than the Asian strain (ECoV-Tokachi09)

Detection, molecular characterization and phylogenetic analysis of G3P[12] and G14P[12] equine rotavirus strains co-circulating in central Kentucky

Equine rotavirus A (ERVA) is the leading cause of diarrhea in neonatal foals and a major health problem to the equine breeding industry worldwide. The G3P[12] and G14P[12] ERVA genotypes are the most prevalent in foals with diarrhea. Control and prevention strategies include vaccination of pregnant mares with an inactivated vaccine containing a prototype ERVA G3P[12] strain with limited and controversial field efficacy. Here, we performed the molecular characterization of ERVA strains circulating in central Kentucky using fecal samples collected during the 2017 foaling season. The data indicated for the first time that the G14P[12] genotype is predominant in this region in contrast to a previous serotyping study where only G3 genotype strains were reported. Overall, analysis of antigenic sites in the VP7 protein demonstrated the presence of several amino acid substitutions in the epitopes exposed on the surface including a non-conserved N-linked glycosylation site (D123N) in G14P[12] strains, while changes in antigenic sites of VP8* were minor. Also, we report the successful isolation of three ERVA G14P[12] strains which presented a high identity with other G14 strains from around the world. These may constitute ideal reference strains to comparatively study the molecular biology of G3 and G14 strains and perform vaccine efficacy studies following heterologous challenge in the future.Instituto de VirologíaFil: Carossino, Mariano. University of Kentucky. Department of Veterinary Science. Maxwell H. Gluck Equine Research Center; Estados Unidos.Universidad del Salvador. Escuela de Veterinaria; ArgentinaFil: Barrandeguy, Maria Edith. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Virología; Argentina. Universidad del Salvador. Escuela de Veterinaria; ArgentinaFil: Li, Yanqiu. University of Kentucky. Department of Veterinary Science. Maxwell H. Gluck Equine Research Center; Estados UnidosFil: Parreño, Viviana. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Virología; ArgentinaFil: Janes, Jennifer. University of Kentucky. Department of Veterinary Science. University of Kentucky Veterinary Diagnostic Laboratory; Estados UnidosFil: Loynachan, Alan T. University of Kentucky. Department of Veterinary Science. University of Kentucky Veterinary Diagnostic Laboratory; Estados UnidosFil: Balasuriya, Udeni B.R. University of Kentucky. Department of Veterinary Science. Maxwell H. Gluck Equine Research Center; Estados Unidos.Universidad del Salvador. Escuela de Veterinaria; Argentin

Genetic variation and phylogenetic analysis of 22 French isolates of equine arteritis virus

International audienceGenetic variation and phylogenetic relationships among 22 French isolates of equine arteritis virus (EAV) obtained over four breeding seasons (2001-2004) were determined by sequencing open reading frames (ORFs) 2a-7. The ORFs 2a-7 of 22 isolates differed from the prototype virulent Bucyrus strain of EAV by between 14 (99.5% identity) and 328 (88.7% identity) nucleotides, and differed from each other by between 0 (100% identity) and 346 (88.1% identity) nucleotides, confirming genetic diversity among EAV strains circulating in France. Phylogenetic analysis based on the partial ORF5 sequences (nucleotides 11296-11813) of 22 French isolates and 216 additional EAV strains available in GenBank clustered the global isolates of EAV into two distinct groups: North American and European. The latter could be further divided into two large subgroups: European subgroup 1 (EU-1) and European subgroup 2 (EU-2). Phylogenetic analysis based on 100 EAV ORF3 sequences yielded similar results. Of the 22 French EAV isolates, the 11 isolates obtained before January 28, 2003 clustered with either the EU-1 (9 isolates) or EU-2 (2 isolates) subgroup. In contrast, by the criteria used in this study, the 11 isolates obtained after January 30, 2003 belong to the North American group, strongly suggesting that these strains were recently introduced into France

First detection of equine coronavirus (ECoV) in Europe

International audienceEquine coronavirus (ECoV) is involved mainly in enteric infections. Following the recent description of ECoV in 2000, this study reports for the first time the presence of ECoV in France and, on a wider scale, in Europe. ECoV was molecularly detected from diarrheic and respiratory specimens. Sequencing and phylogenetic analyses demonstrated that European strains are most closely related to the reference North American strain (ECoV-NC99) than the Asian strain (ECoV-Tokachi09)