title: Venereal shedding of equid herpesvirus-1 (EHV-1) in naturally infected stallions.
abstract: BACKGROUND
  Equid herpesvirus 1 (EHV-1) is a highly prevalent pathogen in horse populations worldwide. Oronasal infection represents the classic route of disease transmission. Venereal shedding of EHV-1 is not regarded relevant in terms of virus spreading, which is in contrast to the close relatives of EHV-1, bovine and suid alphaherpesvirus, for which artificial insemination is a well-documented and accepted means of virus spread.
  
  
  OBJECTIVE
  Documentation of venereal EHV-1 shedding in 3 naturally infected stallions.
  
  
  METHODS
  Three stallions were infected during an acute outbreak by an EHV-1 strain with the G(2254) /D(752) Pol genotype.
  
  
  METHODS
  In this observational study, 12 semen samples from these 3 stallions were tested for EHV-1 to determine venereal shedding. EHV-1 was diagnosed by conventional PCR and paired serum neutralization tests in 42 horses. Semen samples were separated into sperm and seminal plasma fractions and tested for EHV-1 by conventional and quantitative PCR as well as virus isolation by cell culture.
  
  
  RESULTS
  Acute EHV-1 infection was diagnosed on the premise. Five semen samples collected from 2 of the 3 stallions tested positive for EHV-1 by (q)PCR. On days 18 and 20 after onset of fever, the last positive samples were retrieved. All samples were positive in seminal plasma, only three in sperm fraction. Virus isolation attempts were unsuccessful.
  
  
  CONCLUSIONS
  The data presented here document shedding of EHV-1 in semen of naturally infected stallions for close to 3 weeks, which seems not to be directly associated with spermatozoa.
authors.affiliation: Klinik für Reproduktionsmedizin, Vetsuisse-Fakultät Universität Zürich, Zürich, Switzerland. jwalter@vetclinics.uzh.ch
authors.forename: J
authors.initials: J
authors.lastname: Walter
authors.forename: H-J
authors.initials: HJ
authors.lastname: Balzer
authors.forename: C
authors.initials: C
authors.lastname: Seeh
authors.forename: K
authors.initials: K
authors.lastname: Fey
authors.forename: U
authors.initials: U
authors.lastname: Bleul
authors.forename: N
authors.initials: N
authors.lastname: Osterrieder
mesh_terms: D000818:Animals; D000914:Antibodies, Viral; D004196:Disease Outbreaks / Q000662:veterinary; D004861:Herpesvirus 1, Equid / Q000502:physiology*; D006734:Horse Diseases / Q000821:virology*; D006736:Horses; D008297:Male; D012661:Semen / Q000821:virology*; D017201:Virus Shedding / Q000502:physiology*
chemical_list: D000914:Antibodies, Viral