Abstract：
Bovine anaemia caused by Theileria orientalis group (BATOG) causes significant production and economic losses in Australia\'s cattle industry. The pathogenic T. orientalis genotypes reported in Australian cattle are type 1 (Chitose) and type 2 (Ikeda). The present study aimed to determine the prevalence and distribution of T. orientalis genotypes in adult lactating cows in Western Australia (WA) dairy herds. A total of 100 whole blood samples from lactating cows from 10 farms were obtained and screened for T. orientalis using polymerase chain reaction (PCR). Sanger sequencing was subsequently used to characterise T. orientalis genotypes isolated from positive samples. A total of thirteen cows (13%; 95% CI: 7.1-21.2%) were positive for T. orientalis, and six out of ten farms (60%; 95% CI: 26.2-87.8%) housed at least one T. orientalis-positive cow. The distribution of T. orientalis was found to be wide and dense in the South west region of WA and the southern coast of WA. The predominant T. orientalis genotype identified was Ikeda (n = 11, 11%; 95% CI: 5.6-18.8%), while the Buffeli genotype was identified in WA for the first time, albeit at a low prevalence (n = 1, 1%; 95% CI: 0.0-5.4%). This study has provided useful epidemiological evidence on the prevalence and distribution of T. orientalis in adult lactating dairy cows in WA dairy farms, and on the importance of conducting widespread surveillance programs for the understanding of BATOG in WA.
摘要：
在澳大利亚的养牛业中,由东方Theileriagroup(BATOG)引起的牛贫血造成了巨大的生产和经济损失。在澳大利亚牛中报道的致病性T.Orientalis基因型是1型（Chitose）和2型（Ikeda）。本研究旨在确定西澳大利亚州（WA）奶牛群成年泌乳奶牛中东方毛虫基因型的患病率和分布。从10个农场的泌乳母牛中获得总共100个全血样品，并使用聚合酶链反应（PCR）筛选东方毛虫。随后使用Sanger测序来表征从阳性样品中分离的东方毛虫基因型。共有13头牛（13％；95％CI：7.1-21.2％）为东方毛虫阳性，十分之六的农场（60％；95％CI：26.2-87.8％）饲养至少一头东方毛虫阳性母牛。在西澳大利亚州的西南地区和西澳大利亚州的南部海岸，东方毛虫的分布广泛而密集。确定的主要T.Orientalis基因型为Ikeda（n=11，11％；95％CI：5.6-18.8％），虽然Buffeli基因型是首次在西澳地区发现的，尽管患病率较低（n=1，1％；95％CI：0.0-5.4％）。这项研究为西澳奶牛场成年泌乳奶牛中东方毛虫的患病率和分布提供了有用的流行病学证据，以及开展广泛监测计划对了解西澳BATOG的重要性。
