Papakonstantinou Georgios, Meletis Eleftherios, Christodoulopoulos Georgios, Tzika Eleni D, Kostoulas Polychronis, Papatsiros Vasileios G
Clinic of Medicine, Faculty of Veterinary Medicine, School of Health Sciences, University of Thessaly, 43100 Karditsa, Greece.
Laboratory of Epidemiology & Artificial Intelligence, Faculty of Public Health, School of Health Sciences, University of Thessaly, 43100 Karditsa, Greece.
Animals (Basel). 2022 Feb 12;12(4):450. doi: 10.3390/ani12040450.
The objective of the present study was to evaluate the potential risks of the four commercial PRRS-1 MLV vaccines in pregnant vaccinated gilts at the last stage of gestation under field conditions. The study was conducted at four pig farms, including 25 gilts from each farm (25 × 4 = 100 gilts), which were equally allocated to five different study groups. A PRRS-1 MLV vaccination was applied on the 100th day of their pregnancy with the different commercial vaccines that are available in the Greek market. The results indicated virus congenital infection and viremia in piglets (20/200 = 10% PRRSV infected piglets), and detection of PRRSV-specific antibodies (181/200 = 90.5% piglets found with PRRSV antibodies). The subsequent phylogenetic analyses revealed high percentages of similarity between the PRRSV-1 strain detected in infected litters and the PRRSV-1 vaccine strain to which the study gilts had been previously exposed to. Health status analyses of trial piglets resulted in differences between litters from vaccinated sows and litters from non-vaccinated sows at 110th day of gestation as regards the number of weak-born piglets, mummies, and piglets with splay-leg and/or respiratory symptoms. The current study's results indicate several potential dangers of the PRRS MLV vaccination in late gestation.
本研究的目的是评估在田间条件下，四种市售猪繁殖与呼吸综合征1型（PRRS-1）活疫苗对妊娠后期接种疫苗的后备母猪的潜在风险。该研究在四个猪场进行，每个猪场选取25头后备母猪（25×4 = 100头后备母猪），并将它们平均分配到五个不同的研究组。在妊娠第100天时，用希腊市场上可获得的不同市售疫苗对这100头后备母猪进行PRRS-1活疫苗接种。结果表明，仔猪出现病毒先天性感染和病毒血症（20/200 = 10%的仔猪感染PRRSV），并检测到PRRSV特异性抗体（181/200 = 90.5%的仔猪检测到PRRSV抗体）。随后的系统发育分析显示，在受感染仔猪窝中检测到的PRRSV-1毒株与研究后备母猪先前接触过的PRRSV-1疫苗毒株之间有很高的相似百分比。对试验仔猪的健康状况分析表明，在妊娠第110天时，接种疫苗的母猪所产仔猪窝与未接种疫苗的母猪所产仔猪窝在弱仔、木乃伊胎以及出现八字腿和/或呼吸道症状的仔猪数量方面存在差异。当前研究结果表明，在妊娠后期进行PRRS活疫苗接种存在若干潜在危险。
