PMID- 9220631
OWN - NLM
STAT- MEDLINE
DCOM- 19970912
LR  - 20190831
IS  - 0378-1135 (Print)
IS  - 0378-1135 (Linking)
VI  - 55
IP  - 1-4
DP  - 1997 Apr
TI  - Monitoring of porcine reproductive and respiratory syndrome virus infection in 
      boars.
PG  - 337-46
AB  - A major concern exists on transmission of porcine reproductive and respiratory 
      syndrome virus (PRRSV) via semen and effect of vaccination on PRRSV shedding in 
      semen. Recent reports suggest that the virus can be transmitted by semen from 
      boars infected experimentally or from natural sources. Seminal shedding, viremia, 
      and changes in semen quality in boars with or without vaccination were examined. 
      Nine boars were divided into three groups (three boars/group). Group I boars were 
      vaccinated with 2 ml of RespPRRS vaccine (NOBL Laboratory) intramusculary and 
      groups II and III were non-vaccinated. At 28 post-vaccination study days, group I 
      and group II boars were challenged with virulent PRRSV VR-2332 at 2 ml of 10(4.0) 
      TCID50 per boar intranasally. Group III served as non-vaccinated and 
      non-challenged control. Semen and serum samples were collected from -9 
      pre-vaccination study days to 85 post-challenge study days and tested for the 
      presence of PRRSV by virus isolation and reverse transcription-nested polymerase 
      chain reaction (RT-nPCR). Prior to detection of PRRSV RNA from samples, 
      conditions for RT-nPCR were optimized. Two primer sets, an external and an 
      internal, were selected for RT-nPCR. The first round of PCR using an external 
      primer set could detect 10 TCID50 of PRRSV/reaction. However, nested PCR could 
      detect as little as 0.01 TCID50 of PRRSV/reaction. PRRS vaccine virus was not 
      isolated from vaccinated pigs, but the vaccine virus RNA was detected from three 
      boars, at day 6 to 15, 9 to 12, and 15 to 21 post-vaccination by RT-nPCR. 
      Following challenge, two of non-vaccinated/challenged boars shed virus into semen 
      up to 50 and 57 days post-challenge, respectively. The group I vaccinated boars 
      did not shed virus into semen after challenge. The non-vaccinated/challenged 
      group featured sperm abnormalities in the form of significantly increased 
      incidence of proximal droplets and abnormal tails at 36-50 days post-challenge. 
      The latter defect was observed to increase similarly in vaccinated/challenged 
      boars as well.
FAU - Shin, J
AU  - Shin J
AD  - Department of Clinical Population Sciences, College of Veterinary Medicine, 
      University of Minnesota, St. Paul 55108, USA.
FAU - Torrison, J
AU  - Torrison J
FAU - Choi, C S
AU  - Choi CS
FAU - Gonzalez, S M
AU  - Gonzalez SM
FAU - Crabo, B G
AU  - Crabo BG
FAU - Molitor, T W
AU  - Molitor TW
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - Netherlands
TA  - Vet Microbiol
JT  - Veterinary microbiology
JID - 7705469
RN  - 0 (RNA, Viral)
RN  - 0 (Viral Vaccines)
SB  - IM
MH  - Animals
MH  - *Animals, Wild
MH  - Female
MH  - Male
MH  - Polymerase Chain Reaction
MH  - Porcine Reproductive and Respiratory Syndrome/prevention & control/*transmission
MH  - Porcine respiratory and reproductive syndrome virus/immunology/*isolation & 
      purification
MH  - RNA, Viral/blood/isolation & purification
MH  - Semen/*virology
MH  - Sexually Transmitted Diseases, Viral/prevention & 
      control/transmission/*veterinary
MH  - Swine
MH  - Swine Diseases
MH  - Viral Vaccines
MH  - Virus Shedding
EDAT- 1997/04/01 00:00
MHDA- 1997/04/01 00:01
CRDT- 1997/04/01 00:00
PHST- 1997/04/01 00:00 [pubmed]
PHST- 1997/04/01 00:01 [medline]
PHST- 1997/04/01 00:00 [entrez]
AID - S0378-1135(96)01336-3 [pii]
AID - 10.1016/s0378-1135(96)01336-3 [doi]
PST - ppublish
SO  - Vet Microbiol. 1997 Apr;55(1-4):337-46. doi: 10.1016/s0378-1135(96)01336-3.