Department of Aquatic Bioscience, Graduate School of Agriculture, University of Tokyo, Tokyo 113-8657, Japan.
J Invertebr Pathol. 2012 Sep 15;111(1):50-5. doi: 10.1016/j.jip.2012.05.009. Epub 2012 Jun 9.
Manila clams, Ruditapes philippinarum, are widely harvested in the coastal waters in Japan. However, there have been significant decreases in the populations of Manila clams since the 1980s. It is thought that infection with the protozoan Perkinsus species has contributed to these decreases. A previous study demonstrated that high infection levels of a pure strain of Perkinsus olseni (ATCC PRA-181) were lethal to hatchery-raised small Manila clams, however, the pathogenicity of wild strain Perkinsus species to wild Manila clam is unclear. To address this, we challenged large (30-40 mm in shell length) and small (3-15 mm in shell length) wild Manila clams with Perkinsus species isolated from naturally infected wild Manila clams. We report high mortalities among the small clams, but not among the large ones. This is the first report to confirm the pathogenicity of wild isolate of Perkinsus species to wild Manila clams.
菲律宾蛤仔在日本沿海水域被广泛捕捞。然而，自 20 世纪 80 年代以来，菲律宾蛤仔的数量显著减少。人们认为，原生动物派琴虫属的感染是导致这种减少的原因之一。先前的研究表明，高感染水平的纯系派琴虫（ATCC PRA-181）对养殖的小菲律宾蛤仔是致命的，然而，野生派琴虫属对野生菲律宾蛤仔的致病性尚不清楚。为了解决这个问题，我们用从自然感染的野生菲律宾蛤仔中分离出来的派琴虫属对大（壳长 30-40 毫米）小（壳长 3-15 毫米）菲律宾蛤仔进行了挑战。我们报告说，小蛤仔的死亡率很高，但大蛤仔的死亡率并不高。这是第一个证实野生派琴虫属对野生菲律宾蛤仔致病性的报告。
