title: Comparative study on the in vitro and in vivo properties of two bovine herpesvirus-5 reference strains.
abstract: BACKGROUND
  Bovine herpesvirus 5 (BoHV-5) is an alphaherpesvirus responsible for meningoencephalitis in young cattle and it is antigenically and genetically related to bovine herpesvirus 1. BoHV-5 outbreaks are sporadic and restricted in their geographical distribution, being mostly detected in the Southern hemisphere. The N569 and A663 strains are prototypes of the "a" and "b" subtypes of BoHV-5, however, scarce information about their in vitro and in vivo properties is currently available.
  
  
  METHODS
  For the in vitro comparison between BoHV-5 A663 and N569 strains, viral growth kinetics, lysis and infection plaque size assays were performed. Additionally, an experimental infection of cattle with BoHV-5 A663 and N569 strains was carried out. Viral excretion, development of neurological signs, presence of specific antibodies in serum and nasal swabs and presence of latent BoHV-5 DNA in trigeminal ganglion, were analyzed. Histopathological examination of samples belonging to inoculated animals was also performed.
  
  
  RESULTS
  The lytic capacity and the cell-to-cell spread was lower for the A663 strain compared to the N569 strain, however, the production of total infectious viral particles was similar between both strains. Concerning the in vivo properties, the A663 and N569 strains are able to induce similar degrees of pathogenicity in cattle.
  
  
  CONCLUSIONS
  Our results show that the A663 strain used in this study is less adapted to in vitro replication in MDBK cells than the N569 strain and, although slight differences were observed, both strains are able to induce a similar degree of virulence in the natural host.
authors.affiliation: Virology Institute, Veterinary and Agricultural Science Research Centre, National Institute of Agricultural Technology (INTA), N. Repeto y los Reseros s/n, Castelar, Buenos Aires, Argentina.
authors.forename: María F
authors.initials: MF
authors.lastname: Ladelfa
authors.forename: María P
authors.initials: MP
authors.lastname: Del Médico Zajac
authors.forename: Fiorella
authors.initials: F
authors.lastname: Kotsias
authors.forename: Fernando
authors.initials: F
authors.lastname: Delgado
authors.forename: Benoît
authors.initials: B
authors.lastname: Muylkens
authors.forename: Julien
authors.initials: J
authors.lastname: Thiry
authors.forename: Etienne
authors.initials: E
authors.lastname: Thiry
authors.forename: Sonia A
authors.initials: SA
authors.lastname: Romera
mesh_terms: D000818:Animals; D002417:Cattle; D002418:Cattle Diseases / Q000503:physiopathology / Q000635:transmission / Q000821:virology*; D002460:Cell Line; D018792:Encephalitis, Viral / Q000503:physiopathology / Q000635:transmission / Q000662:veterinary* / Q000821:virology; D006566:Herpesviridae Infections / Q000503:physiopathology / Q000635:transmission / Q000662:veterinary* / Q000821:virology; D025881:Herpesvirus 5, Bovine / Q000145:classification / Q000472:pathogenicity / Q000502:physiology*; D008590:Meningoencephalitis / Q000503:physiopathology / Q000635:transmission / Q000662:veterinary* / Q000821:virology; D014774:Virulence