Efficacy of experimentally produced spray-dried plasma on infectivity of porcine circovirus type 2
Efficacy of experimentally produced spray-dried plasma on infectivity of porcine circovirus type 2
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DOI：
10.2527/jas.2009-2696
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发表时间：
2010-12-01
影响因子：
3.3
通讯作者：
Opriessnig, T.
中科院分区：
文献类型：
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作者：
Patterson, A. R.;Madson, D. M.;Opriessnig, T.
将喷雾干燥血浆（SDP）掺入断奶仔猪的饮食中以改善采食量和生长性能的价值已得到充分证明。然而，已经进行了有限的工作来确认喷雾干燥工艺消除了所有病毒污染物，包括猪圆环病毒2型（PCV 2）。为了确定喷雾干燥对PCV 2感染性的影响，将初乳喂养的、杂交的、无特定病原体（SPF）的猪腹膜内（SDP-IP）或经口灌胃（SDP-OG）接种PCV 2污染的SDP，腹膜内接种PCV 2阳性血浆（POS），或保持未接种（NEG）。从实验感染PCV 2b分离株的SPF猪中采集用于实验制备SDP的血浆。NEG组中的猪保持血清阴性，并且未检测到PCV 2病毒血症。POS组所有猪在接种后14 d（DPI）均出现PCV 2病毒血症，28 DPI时血清转化。在SDP-IP组中，所有猪在35 DPI时变为病毒血症，并在49 DPI时发生血清转化。在SDP-OG组中，所有动物在35 DPI时变为病毒血症，2/3头猪在35 DPI时血清转化。POS、SDP-OG或SDP-IP组中猪的抗PCV 2-IgG抗体样本与阳性比率之间无显著差异（P > 0.05）。这项工作提供了直接证据，表明基于使用PCV 2未感染猪的猪生物测定，本研究中使用的实验性喷雾干燥工艺不能有效灭活PCV 2感染猪血浆中的PCV 2b。这项工作表明，来自猪的SDP可能对该行业构成生物安全风险。
The value of incorporating spray-dried plasma (SDP) into the diet of weanling pigs to improve feed intake and growth performance has been well documented. However, limited work has been done to confirm that the spray-drying process eliminates all viral contaminates including porcine circovirus type 2 (PCV2). To determine the effect of spray-drying on PCV2 infectivity, colostrum-fed, crossbred, specific-pathogen-free (SPF) pigs were inoculated with PCV2-contaminated SDP intraperitoneally (SDP-IP) or by oral gavage (SDP-OG), inoculated intraperitoneally with PCV2-positive plasma (POS), or left uninoculated (NEG). The plasma used for the experimentally produced SDP was collected from a SPF pig experimentally infected with a PCV2b isolate. Pigs in the NEG group remained seronegative, and PCV2 viremia was not detected. All pigs in the POS group became PCV2 viremic by 14 d postinoculation (DPI) and seroconverted by 28 DPI. In the SDP-IP group, all pigs became viremic by 35 DPI and seroconverted by 49 DPI. In the SDP-OG group, all animals became viremic by 35 DPI and 2/3 pigs seroconverted by 35 DPI. There were no significant (P > 0.05) differences between anti-PCV2-IgG antibody sample-to-positive ratios among pigs in the POS, SDP-OG, or SDP-IP groups. This work provides direct evidence that the experimental spray-drying process used in this study was not effective in inactivating PCV2b in the plasma of a PCV2-infected pig based on a swine bioassay using PCV2-naive pigs. This work suggests that SDP sourced from pigs could represent a biosecurity risk for the industry.