Blázquez Elena, Pujols Joan, Rodríguez Fernando, Segalés Joaquim, Rosell Rosa, Campbell Joy, Polo Javier
IRTA, Centre de Recerca en Sanitat Animal (CReSA), 08193 Barcelona, Spain.
APC Europe, S.L. 08403 Granollers, Spain.
Vaccines (Basel). 2023 Apr 10;11(4):824. doi: 10.3390/vaccines11040824.
The objective of this study was to evaluate the potential benefits of feeding spray-dried porcine plasma (SDPP) to pigs infected with African swine fever virus (ASFV). Two groups of twelve weaned pigs each were fed with CONVENTIONAL or 8% SDPP enriched diets. Two pigs (trojans)/group) were injected intramuscularly with the pandemic ASFV (Georgia 2007/01) and comingled with the rest of the pigs (1:5 trojan:naïve ratio) to simulate a natural route of transmission. Trojans developed ASF and died within the first week after inoculation, but contact pigs did not develop ASF, viremia, or seroconversion. Therefore, three more trojans per group were introduced to optimize the ASFV transmission (1:2 trojan:naïve ratio). Blood, nasal, and rectal swabs were weekly harvested, and at end of the study ASFV-target organs collected. After the second exposure, rectal temperature of conventionally fed contact pigs increased >40.5 °C while fever was delayed in the SDPP contact pigs. Additionally, PCR Ct values in blood, secretions, and tissue samples were significantly lower ( < 0.05) for CONVENTIONAL compared to SDPP contact pigs. Under these study conditions, contact exposed pigs fed SDPP had delayed ASFV transmission and reduced virus load, likely by enhanced specific T-cell priming after the first ASFV-exposure.
本研究的目的是评估给感染非洲猪瘟病毒（ASFV）的猪喂食喷雾干燥猪血浆（SDPP）的潜在益处。两组断奶仔猪，每组12头，分别喂食常规日粮或添加8% SDPP的日粮。每组两头猪（“特洛伊木马”猪）通过肌肉注射接种大流行的ASFV（格鲁吉亚2007/01毒株），并与其余猪只混养（“特洛伊木马”猪与未感染猪的比例为1:5），以模拟自然传播途径。“特洛伊木马”猪在接种后第一周内出现非洲猪瘟并死亡，但接触猪未出现非洲猪瘟、病毒血症或血清转化。因此，每组再引入三头“特洛伊木马”猪，以优化ASFV传播（“特洛伊木马”猪与未感染猪的比例为1:2）。每周采集血液、鼻腔和直肠拭子，并在研究结束时收集ASFV靶向器官。第二次接触后，常规日粮喂养的接触猪直肠温度升高至>40.5°C，而SDPP接触猪的发热出现延迟。此外，与SDPP接触猪相比，常规日粮喂养的接触猪血液、分泌物和组织样本中的PCR Ct值显著更低（<0.05）。在这些研究条件下，喂食SDPP的接触暴露猪ASFV传播延迟，病毒载量降低，这可能是由于首次接触ASFV后特异性T细胞启动增强所致。
