title: Detection of bovine viral diarrhea virus in semen obtained after inoculation of seronegative postpubertal bulls.
abstract: OBJECTIVE
  To evaluate persistence of bovine viral diarrhea virus (BVDV) in semen after inoculation of postpubertal bulls.
  
  
  METHODS
  Three 2-year-old bulls and five 6-month-old calves.
  
  
  METHODS
  3 seronegative 2-year-old bulls were inoculated intranasally with BVDV. Serum and semen samples were obtained at regular intervals until 7 months after inoculation. Serum samples were tested for BVDV by use of virus isolation (VI) and reverse transcription-nested polymerase chain reaction (RT-nPCR) tests. Semen samples were tested for virus by use of VI and RT-nPCR tests. Testicular biopsy specimens were obtained 7 months after inoculation and tested for BVDV by use of immunohistochemical analysis and VI and RT-nPCR tests. Semen samples collected from 1 bull immediately before and 5 and 7 months after inoculation were administered IV to seronegative calves, which were monitored for subsequent viremia and seroconversion.
  
  
  RESULTS
  Use of VI and RT-nPCR tests detected transient virus in serum of all bulls. The VI test detected BVDV in semen of 2 bulls for < 21 days after inoculation, whereas RT-nPCR assay detected BVDV until 7 months after inoculation. Virus was detected in testicular biopsy specimens of these 2 bulls by use of immunohistochemical analysis and RT-nPCR assay but could only be isolated from the biopsy specimen of 1 bull. Of the calves administered semen IV to detect infectious virus, only the recipient of semen collected 5 months after inoculation of the adult bull was viremic and seroconverted.
  
  
  CONCLUSIONS
  Bovine viral diarrhea virus can persist in semen of acutely infected bulls for several months after exposure.
authors.affiliation: Department of Pathobiology, College of Veterinary Medicine, Auburn University, Auburn University, AL 36849, USA.
authors.forename: M Daniel
authors.initials: MD
authors.lastname: Givens
authors.forename: Allen M
authors.initials: AM
authors.lastname: Heath
authors.forename: Kenny V
authors.initials: KV
authors.lastname: Brock
authors.forename: Bruce W
authors.initials: BW
authors.lastname: Brodersen
authors.forename: Robert L
authors.initials: RL
authors.lastname: Carson
authors.forename: David A
authors.initials: DA
authors.lastname: Stringfellow
mesh_terms: D000818:Animals; D001483:Base Sequence; D001912:Bovine Virus Diarrhea-Mucosal Disease / Q000821:virology; D002417:Cattle / Q000821:virology*; D001908:Diarrhea Viruses, Bovine Viral / Q000235:genetics / Q000302:isolation & purification* / Q000502:physiology*; D007150:Immunohistochemistry; D008297:Male; D008969:Molecular Sequence Data; D012661:Semen / Q000821:virology*; D012741:Sexual Maturation; D013737:Testis / Q000821:virology; D014766:Viremia / Q000821:virology