Khan Sakandar, Cable Jo, Younus Muhammad, Rashid Muhammad Imran, Hailer Frank, Akbar Haroon
Department of Parasitology, Faculty of Veterinary Sciences, University of Veterinary and Animals Sciences, Lahore 54000, Pakistan.
School of Biosciences, Cardiff University, Cardiff CF10 3AX, UK.
Animals (Basel). 2023 Feb 27;13(5):866. doi: 10.3390/ani13050866.
Cystic echinococcosis (hydatidosis) is a world-wide zoonotic disease of mainly humans, livestock and dogs, caused by . The disease can negatively impact food production and animal welfare and causes socio-economic hardship. Here, we aimed to identify the local bovine hydatid cyst fluid (BHCF) antigen for developing a sero-diagnostic assay to be used for the pre-slaughter screening of food animals. In total, 264 bovines approved for slaughter in Pakistan were subjected to serum collection and post-mortem screening for hydatid cysts. These cysts were assessed microscopically to assess fertility and viability, and by PCR for molecular confirmation of species. A BHCF antigen was identified from positive sera via SDS-PAGE, confirmed by Western blot, and quantified via a bicinchoninic acid (BCA) assay. The quantified crude BHCF antigen (iEg67 kDa) was then used in ELISA screening to test all sera collected from known positive and negative animals based on hydatid cyst presence/absence. Of the 264 bovines examined, 38 (14.4%) showed hydatid cysts during post-mortem examination. All of these individuals, plus an additional 14 (total: 52; 19.6%) tested positive based on less time-consuming ELISA examination. Based on ELISA, occurrence in females (18.8%) was significantly higher than in males (9.2%) and was higher in cattle (19.5%) compared to buffalo (9.5%). The infection rate increased with age in both host species: cumulatively, 3.6% in animals aged 2-3 years, 14.6% in 4-5-year-olds and 25.6% in 6-7-year-olds. The occurrence of cysts in cattle was significantly higher in the lungs (14.1%) compared to their livers (5.5%), whereas the opposite was true in buffalo (6.6% livers, 2.9% lungs). For both host species, most cysts in the lungs were fertile (65%), while the majority in the liver were sterile (71.4%). We conclude that the identified iEg67 kDa antigen is a strong candidate for the development of a sero-diagnostic screening assay for the pre-slaughter diagnosis of hydatidosis.
囊型棘球蚴病（包虫病）是一种主要发生于人类、家畜和犬类的全球性人畜共患病，由……引起。该疾病会对食品生产和动物福利产生负面影响，并造成社会经济困难。在此，我们旨在鉴定本地牛包虫囊肿液（BHCF）抗原，以开发一种血清诊断检测方法，用于食品动物的宰前筛查。总共对巴基斯坦264头经批准屠宰的牛进行了血清采集和死后包虫囊肿筛查。对这些囊肿进行显微镜检查以评估其生育能力和活力，并通过聚合酶链反应（PCR）进行物种分子确认。通过十二烷基硫酸钠 - 聚丙烯酰胺凝胶电泳（SDS - PAGE）从阳性血清中鉴定出一种BHCF抗原，通过蛋白质印迹法进行确认，并通过二辛可宁酸（BCA）测定法进行定量。然后将定量的粗制BHCF抗原（iEg67 kDa）用于酶联免疫吸附测定（ELISA）筛查，以检测根据包虫囊肿存在与否从已知阳性和阴性动物收集的所有血清。在检查的264头牛中，38头（14.4%）在死后检查中发现有包虫囊肿。所有这些个体，加上另外14头（总计52头；19.6%），基于耗时较少的ELISA检查呈阳性。基于ELISA，雌性（18.8%）的发病率显著高于雄性（9.2%），并且牛（19.5%）的发病率高于水牛（9.5%）。两种宿主动物的感染率均随年龄增加：2至3岁动物累计感染率为3.6%，4至5岁动物为14.6%，6至7岁动物为25.6%。牛的囊肿在肺部的发生率（14.1%）显著高于肝脏（5.5%），而水牛则相反（肝脏6.6%，肺部2.9%）。对于两种宿主动物，肺部的大多数囊肿具有生育能力（65%），而肝脏中的大多数囊肿是不育的（71.4%）。我们得出结论，鉴定出的iEg67 kDa抗原是开发用于包虫病宰前诊断的血清诊断筛查检测方法的有力候选物。
