■绵羊和山羊Theileriosis是一种蜱传播的嗜血原虫病,由Theileriaspp引起。,在高死亡率和高发病率方面造成重大经济损失。诊断绵羊的头颅侧凸主要基于临床症状,染色血涂片的显微镜筛查,淋巴结活检涂片,但是这些检测方法对Theileriaspp的局限性。感染限制了它们的特异性。
■为了克服这些限制,目前的研究报告了通过血液涂片检查和聚合酶链反应(PCR)在巴基斯坦小反刍动物中的鉴别诊断。
■该研究是在1,200只明显健康的小反刍动物(737只绵羊和463只山羊)上进行的。首先,在血涂片中筛查红细胞中是否存在Theileriapirosoma.第二,通过使用对Theileriaspp具有特异性的引物进行基于18SrRNA基因的PCR扩增。
■在检查的1200个血液涂片样本中,发现100只动物(8.33%)对Theileria物种呈阳性,其中显示了点和逗号形状的红细胞内主体。从737只绵羊和463只山羊的随机收集的血液样本中扩增分离的DNA表明,1,098bp的扩增子大小对Theileriaspp呈阳性。总的来说,在这项研究中检查的1200只小反刍动物中有315只对Theileriaspp呈阳性。DNA通过PCR扩增。值得注意的是,在885份PCR扩增阴性的血液样本中,只有15份血液样本经血涂片检查呈阳性。相反,在涂片技术中测试为阴性的230份血液样品通过PCR扩增产生了特定的条带。总的来说,血涂片法的敏感性和特异性分别为26.98%和98.31%,PCR法的敏感性和特异性分别为73.01%和100%,分别。
■我们的发现表明,与传统的涂片检查方法相比,PCR是巴基斯坦诊断绵羊和山羊的黄金标准方法。
Ovine and caprine theileriosis is a tick-borne hemoprotozoan disease, caused by Theileria spp., responsible for heavy economic losses in terms of high mortality and morbidity rates. Diagnosis of ovine theileriosis is primarily based on clinical symptoms, microscopic screening of stained blood smears, and lymph node biopsy smears, but the limitations of these detection methods against Theileria spp. infection limits their specificity.
To overcome these limitations, the current study reports the differential diagnosis of theileriosis through a blood smear examination and polymerase chain reaction (PCR) in small ruminants from Pakistan.
The study was conducted on 1,200 apparently healthy small ruminants (737 sheep and 463 goats). First, blood smears were screened for the presence of Theileria piroplasms in red blood cells. Second, PCR amplification based on 18S rRNA gene was performed by using primers specific to Theileria spp.
Out of the 1,200 samples of examined blood smears, 100 animals (8.33%) were found positive for Theileria species, which showed intra-erythrocytic bodies in the form of dot and comma shapes. Amplification of the isolated DNA from randomly collected blood samples of 737 sheep and 463 goats showed that an amplicon size of 1,098 bp was positive for Theileria spp. In total, 315 out of the 1,200 small ruminants examined in this study were found positive for Theileria spp. DNA through PCR amplification. Notably, out of the 885 blood samples negative by PCR amplification, only 15 blood samples were found positive by the blood smear test. Conversely, 230 blood samples that tested negative in the smear technique produced a specific band through PCR amplification. Overall, the sensitivity and specificity rates were 26.98% and 98.31% for the blood smear method and 73.01% and 100% for the PCR assay, respectively.
Our finding suggests that PCR is the gold standard method compared to the conventional method of smear examination for the diagnosis of ovine and caprine theileriosis in Pakistan.