Abstract

In poultry industry, mycoplasmas cause large economic losses. The pathogenic significance of mycoplasmas varies widely between species. In birds where vocalization is crucial for reproductive success, mycoplasmas seem to be absent. Birds with high mycoplasma prevalence like birds of prey and storks do not rely on their vocalization for reproduction. Corvids with an intermediate prevalence use other strategies besides vocalization for mating. It is hypothesized that mycoplasma prevalence and vocalization used for reproduction is evolutionary related. Barn swallows have two traits relevant for mating: tail feather length and vocalization. An intermediate prevalence is expected. Little is known about mycoplasmas in barn swallows and their role as vector or reservoir for poultry pathogenic mycoplasmas. This study investigates the prevalence of mycoplasmas in barn swallows and their relevance for mycoplasma transmission to poultry. Choanal swabs from 188 healthy barn swallow nestlings of 59 different nests from ten different colonies on farms were examined for mycoplasmas by cultivation and genus-specific PCR including molecular biological differentiation of the species. In total, in 31 of 188 barn swallows (16.49%) and in 14 of the 59 nests (23.73%), mycoplasmas were detected. The occurrence of mycoplasmas per colony ranged from 0 to 50% independent of poultry being kept on the farm. In all positive samples, Mycoplasma sturni was identified. Mycoplasma sturni seems not to be an obligatory pathogen for barn swallows and occurs with an expected intermediate prevalence in them, so the results support the described hypothesis and underline a minor role of barn swallows for mycoplasma infection in poultry.

中文翻译：

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德国自由放养家燕 (Hirundo rustica) 中斯特尼支原体的发生情况和相关性

摘要

在家禽业中，支原体造成巨大的经济损失。支原体的致病意义在不同物种之间差异很大。在发声对于繁殖成功至关重要的鸟类中，支原体似乎不存在。支原体流行率较高的鸟类，如猛禽和鹳，并不依赖发声进行繁殖。中等流行率的鸦科动物除了发声外还使用其他策略进行交配。据推测，支原体的流行和用于繁殖的发声与进化有关。家燕有两个与交配相关的特征：尾羽长度和发声。预计患病率中等。人们对家燕中的支原体及其作为家禽致病性支原体载体或储存库的作用知之甚少。本研究调查了家燕中支原体的流行情况及其与支原体传播给家禽的相关性。通过培养和属特异性 PCR（包括物种的分子生物学分化）对来自农场 10 个不同群体的 59 个不同巢的 188 只健康家燕雏鸟的后鼻拭子进行了支原体检查。总共在 188 只家燕中的 31 只（16.49%）和 59 个燕窝中的 14 个（23.73%）中检测到支原体。每个菌落支原体的发生率在 0% 到 50% 之间，与农场饲养的家禽无关。在所有阳性样本中， 均鉴定出斯图尼支原体。斯图尼支原体似乎不是家燕的必然病原体，并且在家燕中以预期的中等流行率发生，因此结果支持所描述的假设，并强调家燕在家禽支原体感染中的次要作用。