Di Bartolo Ilaria, De Sabato Luca, Chelli Eleonora, Alborali Giovanni Loris, Tonni Matteo, Monini Marina, De Lucia Alessia, Ostanello Fabio
Department of Food Safety, Nutrition and Veterinary Public Health, Istituto Superiore di Sanità, 00161 Rome, Italy.
Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia-Romagna, 25124 Brescia, Italy.
Animals (Basel). 2020 Jul 9;10(7):1168. doi: 10.3390/ani10071168.
Identifying Hepatitis E virus (HEV)-positive pig farms is important to implement surveillance programs for this emerging zoonotic agent. The aim of this study was to evaluate the use of serosanguineous fluids obtained as part of castration practice (processing fluids (PFs)) to detect anti-HEV antibodies in newborn piglets. Ninety-five paired serum and PF samples were collected from piglets of 29 different litters and tested with a commercial ELISA kit. A significant positive correlation (Spearman's : 0.600; < 0.01) was found between anti-HEV antibodies in serum and PF samples. In 26 out of 29 litters (89.7%), there was at least one positive piglet in the serum. Sixteen litters out of 29 (55.2%) were also positive in PFs. To simulate the use of PF as pooled samples, the limit of detection of the ELISA was assessed mixing the PF sample with strong, medium, medium-weak and weak ELISA titres with 3, 4, 5 and 6 negative PF samples. Our results suggest that it is still possible to identify a positive PF pool when at least one individual PF sample with medium or strong antibody levels is mixed with 5 or 6 individual negative PF samples. The detection of anti-HEV maternal-derived antibodies in PF confirms a past exposure of sows to the virus. PF may represent a rapid, noninvasive and economical tool to identify HEV-positive farms.
识别戊型肝炎病毒（HEV）阳性猪场对于实施针对这种新出现的人畜共患病原体的监测计划至关重要。本研究的目的是评估将作为去势操作一部分获得的血清血性液体（加工液（PFs））用于检测新生仔猪中抗HEV抗体的情况。从29窝不同仔猪中采集了95对血清和PF样本，并用商用ELISA试剂盒进行检测。血清和PF样本中的抗HEV抗体之间存在显著正相关（Spearman氏相关系数：0.600；P<0.01）。在29窝中的26窝（89.7%）中，血清中至少有一头仔猪呈阳性。29窝中的16窝（55.2%）在PF中也呈阳性。为了模拟将PF用作混合样本的情况，通过将PF样本与具有强、中、中弱和弱ELISA滴度的样本分别与3、4、5和6个阴性PF样本混合来评估ELISA的检测限。我们的结果表明，当至少一个抗体水平为中等或强的单个PF样本与5或6个单个阴性PF样本混合时，仍有可能识别出阳性PF混合样本。在PF中检测到抗HEV母源抗体证实母猪过去曾接触过该病毒。PF可能是一种快速、非侵入性且经济的工具，用于识别HEV阳性猪场。
