Joo H S, Park B K, Dee S A, Pijoan C
College of Veterinary Medicine, University of Minnesota, St. Paul 55108, USA.
Vet Microbiol. 1997 Apr;55(1-4):303-7. doi: 10.1016/s0378-1135(96)01332-6.
IgG and IgM antibody responses were examined by an indirect fluorescent antibody method in pigs following inoculation with different porcine reproductive and respiratory syndrome virus (PRRSV) isolates or a vaccine virus. Viremia was also examined in the pigs. The IgG antibody was first detected between 9 and 14 days post inoculation (PI) and maintained high titers for at least 7 weeks PI. No change in IgG antibody titers was observed when the pigs were reinoculated with PRRSV 35 days PI. IgM antibody was detected between 5 and 28 days PI in the pigs. Reinoculation at 35 days PI caused a short term rise of IgM antibody. Virus was isolated from sera collected between 2 and 21 days PI. The IgM antibody was detected regularly in sera collected during viremia and up to 1-2 weeks after the viremic periods. These results suggest that pigs with detectable IgM antibody are probably pigs with recent infection and that routine testing of IgM antibody in purchased breeding pigs from seropositive farms may be useful in identification of pigs with recent infection.
采用间接荧光抗体法检测了接种不同猪繁殖与呼吸综合征病毒（PRRSV）分离株或疫苗病毒后的猪的IgG和IgM抗体反应。还对这些猪进行了病毒血症检测。IgG抗体在接种后（PI）9至14天首次检测到，并在接种后至少7周维持高滴度。接种后35天用PRRSV再次接种猪时，未观察到IgG抗体滴度变化。猪在接种后5至28天检测到IgM抗体。接种后35天再次接种导致IgM抗体短期升高。在接种后2至21天收集的血清中分离到病毒。在病毒血症期间及病毒血症期后1至2周内收集的血清中定期检测到IgM抗体。这些结果表明，可检测到IgM抗体的猪可能是近期感染的猪，对来自血清阳性农场的购进种猪进行IgM抗体常规检测可能有助于识别近期感染的猪。
