Department of Parasitology and Zoology, Faculty of Veterinary Science, Szent István University, István u. 2, 1078 Budapest, Hungary.
Vet Microbiol. 2011 Sep 28;152(3-4):411-4. doi: 10.1016/j.vetmic.2011.04.031. Epub 2011 Apr 28.
The present study was carried out in a herd with concurrent infections of Mycoplasma wenyonii and 'Candidatus M. haemobos', to investigate if transplacental and/or vector-borne transmission is possible for one or both bovine haemoplasma species. For this purpose blood samples were collected from 38 mother animals and their newborn calves; as well as from 17 uninseminated cows twice three months apart. In addition, 311 mosquitoes and blood-sucking flies (Diptera: Culicidae, Tabanidae, Muscidae) were cought near the animals. DNA was extracted from all samples, followed by real-time PCR analysis. In 10.5% of neonate calves, that were born to cows harbouring both haemoplasmas, M. wenyonii and/or 'Candidatus M. haemobos' positivity was detected. Copy numbers in positive samples from cows and their calves indicated that - in comparison with M. wenyonii - 'Candidatus M. haemobos'-bacteraemia had usually lower levels. In samples of uninseminated cows the rate of infection with the latter species decreased. These findings may explain why M. wenyonii was significantly more frequently detected in blood-sucking flies, than 'Candidatus M. haemobos'. In conclusion, molecular evidence is provided for the first time on the transplacental transmission of bovine haemoplasmas. Regarding their spread by blood-sucking arthropods, new potential vectors were identified, i.e. the horn fly (Haematobia irritans), the stable fly (Stomoxys calcitrans) and two species of horse flies (Tabanus bovinus, T. bromius).
本研究在同时感染支原体和“牛嗜血支原体”的牛群中进行，旨在研究一种或两种牛嗜血支原体是否可以通过胎盘或媒介传播。为此，从 38 头母畜及其新生牛犊以及 17 头未配种的奶牛（每 3 个月采血两次）采集了血液样本。此外，在动物附近捕获了 311 只蚊子和吸血蝇（双翅目：蚊科、虻科、蝇科）。从所有样本中提取 DNA，然后进行实时 PCR 分析。在由同时携带支原体和/或“牛嗜血支原体”的牛所生的 10.5%的新生牛犊中，检测到了支原体的阳性。来自牛及其牛犊的阳性样本中的拷贝数表明，与支原体相比，“牛嗜血支原体”菌血症的水平通常较低。未配种奶牛样本中，后者的感染率下降。这些发现可能解释了为什么在吸血蝇中检测到支原体的频率明显高于“牛嗜血支原体”。总之，首次提供了牛嗜血支原体通过胎盘传播的分子证据。关于它们通过吸血节肢动物传播，发现了新的潜在媒介，即牛角蝇（Haematobia irritans）、厩螫蝇（Stomoxys calcitrans）和两种马蝇（Tabanus bovinus、T. bromius）。
