Guevara Soto M, Vidondo B, Vaughan L, Rubin J-F, Segner H, Samartin S, Schmidt-Posthaus H
Centre of Fish and Wildlife Health, Department of Infectious Diseases and Pathobiology, University of Bern, Bern, Switzerland.
Institute of Veterinary Public Health, University of Bern, Bern, Switzerland.
J Fish Dis. 2017 Jun;40(6):811-819. doi: 10.1111/jfd.12562. Epub 2016 Sep 27.
Epitheliocystis in Swiss brown trout (Salmo trutta) is a chlamydial infection, mainly caused by Candidatus Piscichlamydia salmonis and Candidatus Clavichlamydia salmonicola. To gain a better understanding of the temporal development of infections in wild brown trout, we investigated epitheliocystis infections during the course of the summer and autumn months of a single year (2015), and compared this to sampling points over the span of the years 2012-2014. The survey focused on tributaries (Venoge and Boiron) of the Rhone flowing in to Lake Geneva. When evaluated histologically, epitheliocystis infections were found throughout the period of investigation with the exception of the month of June. Fifty to 86 animals per sampling were investigated. Highest prevalence and infection intensities were seen in September. A correlation between epitheliocystis infection and water temperatures was not evident. Interyear comparison revealed consistent levels of prevalence and infection intensities in late summer. The absence of infections in June, combined with the consistent interyear results, indicates seasonal fluctuation of epitheliocystis infections in brown trout with a reservoir persisting during winter months from which infections can re-initiate each year. This could either be at levels below detection limits within the brown trout population itself or in an alternative host.
瑞士褐鳟（Salmo trutta）的上皮囊肿病是一种衣原体感染，主要由鲑鱼嗜衣原体（Candidatus Piscichlamydia salmonis）和鲑鱼棒状衣原体（Candidatus Clavichlamydia salmonicola）引起。为了更好地了解野生褐鳟感染的时间发展情况，我们调查了某一年（2015年）夏季和秋季期间的上皮囊肿病感染情况，并将其与2012 - 2014年期间的采样点进行了比较。该调查集中在流入日内瓦湖的罗纳河支流（韦诺格河和布瓦龙河）。经组织学评估，除6月外，在整个调查期间均发现了上皮囊肿病感染。每个采样点调查50至86条鱼。9月的患病率和感染强度最高。上皮囊肿病感染与水温之间没有明显的相关性。跨年比较显示夏末的患病率和感染强度水平一致。6月未发现感染，再加上跨年结果一致，表明褐鳟上皮囊肿病感染存在季节性波动，在冬季有一个感染源持续存在，每年感染可由此重新开始。这可能是褐鳟种群中低于检测限的水平，也可能存在于替代宿主中。
