Ghafar Abdul, Shaukat Waseem, Waqas Muhammad, Gauci Charles G, Gasser Robin B, Jabbar Abdul
Melbourne Veterinary School, The University of Melbourne, Werribee, VIC 3030, Australia.
Faculty of Veterinary Medicine, University of Calgary, Calgary, AB T2N 1N4, Canada.
Pathogens. 2025 May 20;14(5):499. doi: 10.3390/pathogens14050499.
Bovine anaplasmosis, caused by , is a major tick-borne disease in tropical and subtropical regions of the world, leading to significant production losses. Prolonged convalescence periods are common and surviving animals often become subclinical carriers. This study aimed to detect and characterise A. marginale in bovines in smallholder dairy farms across diverse climatic zones of Pakistan using molecular methods. In total, 321 blood DNA samples from apparently healthy cattle (n = 174) and buffaloes (n = 147) from six districts in Pakistan were tested for A. marginale using a nested PCR assay, targeting part of the major surface protein B gene (msp1β) as a genetic marker, followed by agarose gel electrophoresis and selective sequencing of amplicons from test-positive samples. Of the 321 DNA samples tested, 135 (42.1%) were test-positive for A. marginale. Prevalence was significantly higher in cattle (64.4%; 112/174) than in buffaloes (15.6%; 23/147), and female bovines (43.5%; 108/248) were more frequently infected than males (37%; 27/73). Phylogenetic analysis of the msp1β sequence data (n = 42) revealed that A. marginale from Pakistan clustered with those from Brazil, Thailand, South Africa, and the USA. This study represents the first comprehensive investigation of A. marginale from bovines from diverse agroecological zones of Pakistan and will further stimulate population genetic studies of A. marginale and investigations into the economic impact of subclinical infections in bovines in smallholder farming systems.
牛无形体病由[病原体名称未给出]引起，是世界热带和亚热带地区一种主要的蜱传疾病，会导致重大的生产损失。恢复期延长很常见，存活下来的动物往往会成为亚临床携带者。本研究旨在使用分子方法检测和鉴定巴基斯坦不同气候区小农户奶牛场牛体内的边缘无形体。总共对来自巴基斯坦六个地区看似健康的牛（n = 174）和水牛（n = 147）的321份血液DNA样本进行了边缘无形体检测，采用巢式PCR检测法，以主要表面蛋白B基因（msp1β）的一部分作为遗传标记，随后进行琼脂糖凝胶电泳，并对检测呈阳性样本的扩增子进行选择性测序。在检测的321份DNA样本中，135份（42.1%）边缘无形体检测呈阳性。牛的患病率（64.4%；112/174）显著高于水牛（15.6%；23/147），雌性牛（43.5%；108/248）比雄性牛（37%；27/73）更易感染。对msp1β序列数据（n = 42）的系统发育分析表明，来自巴基斯坦的边缘无形体与来自巴西、泰国、南非和美国的边缘无形体聚类在一起。本研究是对巴基斯坦不同农业生态区牛体内边缘无形体的首次全面调查，将进一步推动边缘无形体的群体遗传学研究以及对小农户养殖系统中牛亚临床感染经济影响的调查。
