Saarinen M, Taskinen J
Department of Biological and Environmental Science, University of Jyväskylä, P.O. Box 35, FIN-40014 University of Jyväskylä, Finland.
J Parasitol. 2003 Dec;89(6):1167-71. doi: 10.1645/GE-3238.
The aim of this study was to develop a method to kill or expel the gill-dwelling crustacean parasite Paraergasilus rylovi from a common freshwater clam, Anodonta piscinalis. Naturally infected clams were exposed to different water-quality treatments and monitoring in the laboratory. In a high-temperature treatment (26 C vs. control 18 C), the mean abundance of the parasite decreased to near zero in 7 days. Because only 2 clams of 72 died in this treatment during the 14-day experiment, the survival of the host was not seriously at risk at the high temperature. 'Low oxygen, no water change' (18 C) was the second most effective treatment, followed by a 'low-oxygen, water-flow' (18 C) treatment. At the end of the experiment, the mean parasite abundance was significantly lower in all the treatments than in the control clams (18 C). A few P. rylovi individuals abandoned the host at 26 C but died in a couple of days outside the host. However, the parasites lived on average (+/-SE) 12.7 +/- 0.9 days outside the clam, and were also shown to be capable of infecting another uninfected host individual, at 18 C. The results of the present study suggest that high temperature provides an effective, ecologically sustainable method to manipulate the intensity of P. rylovi infection.
本研究的目的是开发一种方法，以杀死或驱除常见淡水蚌类池沼圆田螺鳃部寄生的甲壳类寄生虫罗氏副锚头蚤。将自然感染的蚌类置于实验室中，进行不同水质处理并监测。在高温处理组（26℃，对照组为18℃）中，寄生虫的平均丰度在7天内降至接近零。在为期14天的实验中，该处理组72只蚌类中仅有2只死亡，因此在高温下宿主的生存并未受到严重威胁。“低氧，不换水”（18℃）是第二有效的处理方式，其次是“低氧，水流”（18℃）处理。实验结束时，所有处理组中寄生虫的平均丰度均显著低于对照蚌类（18℃）。一些罗氏副锚头蚤个体在26℃时离开宿主，但在离开宿主几天后死亡。然而，在18℃时，这些寄生虫在蚌体外平均存活（±标准误）12.7±0.9天，并且还显示能够感染另一只未感染的宿主个体。本研究结果表明，高温提供了一种有效且生态可持续的方法来控制罗氏副锚头蚤感染的强度。
