Department of Animal Health, NEIKER - Instituto Vasco de Investigación y Desarrollo Agrario, Berreaga 1, 48160 Derio, Bizkaia, Spain.
Vet Parasitol. 2012 Dec 21;190(3-4):318-25. doi: 10.1016/j.vetpar.2012.07.024. Epub 2012 Jul 27.
Bovine piroplasmosis are tick-borne protozoan diseases caused by parasites of the genera Theileria and Babesia. Three Friesian cattle farms (F1-F3) with previous history of clinical piroplamosis were selected in Minorca (Balearic Islands, Spain). Blood samples were collected from 8 to 11 animals every two months throughout a year and, a newly developed multiplex DNA bead-based suspension array based on the Luminex(®) xMAP technology was used to monitor for the presence of piroplasms. The assay incorporated probes for Babesia divergens, Babesia bovis, Babesia bigemina, Babesia major, Babesia occultans, Theileria annulata and Theileria buffeli, and a Catch-all Theileria and Babesia (TB) control probe. An internal amplification control that was detected with a Luminex probe was also included to monitor for inhibition. Infection was detected in 87.5% of the samples, 38.7% as single infections and 48.8% as mixed infections. T. annulata was widespread in Farm F1, with all animals positive over the whole study; albeit less frequently, T. annulata was also detected in Farms F2 and F3. T. buffeli was the overall most prevalent piroplasm, with a wide distribution in Farms F2 and F3 but only occasionally detected in F1. B. bigemina was the most frequent Babesia species, but was absent from Farm F1. B. bovis, previously reported in Minorca, was only sporadically detected in F2 and F3. A further 3 Babesia species not previously found in Minorca were also identified: B. major present in the 3 farms; B. divergens detected once in 2 animals in F2; and B. occultans found in 4 animals in F2 and in 1 Hyalomma marginatum female tick collected from a positive animal. Sequencing confirmed the identity of B. occultans thus extending the distribution of this species to Mediterranean Europe. This study confirmed the endemic situation for piroplasm infection in the region and detected the presence of a large number of chronic asymptomatic carriers. More importantly, 3 Babesia species not previously detected in the region were detected for the first time.
牛梨形虫病是由泰勒虫属和巴贝斯虫属寄生虫引起的蜱传原生动物病。在西班牙巴利阿里群岛的梅诺卡岛选择了三家有临床梨形虫病病史的弗里斯兰牛场(F1-F3)。在一年中每隔两个月从 8 到 11 头动物收集血液样本,并使用新开发的基于微珠的多重 DNA 悬浮阵列基于 Luminex(®) xMAP 技术来监测梨形虫的存在。该检测方法包括巴贝斯虫 divergens、牛巴贝斯虫、双芽巴贝斯虫、巴贝斯虫 major、巴贝斯虫 occultans、环形泰勒虫和布氏泰勒虫的探针,以及一个通用的泰勒虫和巴贝斯虫(TB)对照探针。还包括一个用 Luminex 探针检测到的内部扩增对照,以监测抑制情况。在 87.5%的样本中检测到感染,38.7%为单一感染,48.8%为混合感染。F1 农场广泛存在环形泰勒虫,整个研究期间所有动物均呈阳性;尽管较少见,但在 F2 和 F3 农场也检测到了环形泰勒虫。布氏泰勒虫是最普遍的梨形虫,在 F2 和 F3 农场广泛分布,但在 F1 农场偶尔检测到。双芽巴贝斯虫是最常见的巴贝斯虫种,但在 F1 农场不存在。先前在梅诺卡岛报道的牛巴贝斯虫仅在 F2 和 F3 中偶尔检测到。还鉴定出另外 3 种以前未在梅诺卡岛发现的巴贝斯虫:3 个农场都存在巴贝斯虫 major;在 F2 的 2 只动物中检测到 1 次巴贝斯虫 divergens;在 F2 的 4 只动物和 1 只从阳性动物采集的边缘硬蜱雌蜱中发现巴贝斯虫 occultans。测序证实了巴贝斯虫 occultans 的身份,从而将该物种的分布扩展到地中海欧洲。本研究证实了该地区梨形虫感染的地方性,并检测到大量慢性无症状携带者。更重要的是,首次检测到该地区以前未检测到的 3 种巴贝斯虫。