Summary In order to control saprolegniosis in Prussian carp (Carassius gibelio (Bloch, 1782) eggs, it is important to screen herb extracts as potential anti‐Saprolegnia drugs in Prussian carp hatcheries. For this purpose, an oomycete water mould (strain SC) isolated from Prussian carp [Carassius gibelio (Bloch, 1782)] eggs suffering from saprolegniosis was characterised morphologically as well as from ITS rDNA sequence data. Initially identified as a Saprolegnia sp. based on its morphological features, the constructed phylogenetic tree using the neighbour joining method further indicated that the SC strain was closely related to Saprolegnia australis R. F. Elliott 1968 strain VI05733 (GenBank accession no. HE798564), and which could form biofilm communities as virulence factors. In addition, aqueous extracts from forty Chinese herbs were screened as possible anti‐Saprolegnia agents. Among them, a 1 g ml−1 extract from Radix sanguisorbae was the most efficacious anti‐Saprolegnia agent, indicated by the minimum inhibitory concentration that was as low as 256 mg L−1. Relative survival of 73 and 88% was obtained against the SC strain in fish eggs at concentrations of 256 and 1280 mg L−1, respectively. This is the first known report of Saprolegnia australis R. F. Elliott 1968 infection in C. gibelio (Bloch, 1782) eggs involving the screening of R. sanguisorbae extracts as potential anti‐Saprolegnia agents.

中文翻译：

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澳大利亚水霉R. F. Elliott 1968 普鲁士鲤鱼Carassius gibelio(Bloch, 1782) 卵感染及其用草药提取物控制

筛选了 40 种中草药的水提取物作为可能的抗水霉剂。其中，1 g ml-1 的山竹提取物是最有效的抗水霉剂，最低抑菌浓度低至 256 mg L-1。在 256 和 1280 mg L-1 的浓度下，鱼卵中 SC 菌株的相对存活率分别为 73% 和 88%。这是第一个已知的关于南方水霉 RF Elliott 1968 在 C. gibelio (Bloch, 1782) 卵中感染的报告，涉及筛选作为潜在抗水霉剂的 R. sanguisorbae 提取物。在 256 和 1280 mg L-1 的浓度下，鱼卵中 SC 菌株的相对存活率分别为 73% 和 88%。这是第一个已知的关于南方水霉 RF Elliott 1968 在 C. gibelio (Bloch, 1782) 卵中感染的报告，涉及筛选作为潜在抗水霉剂的 R. sanguisorbae 提取物。在 256 和 1280 mg L-1 的浓度下，鱼卵中 SC 菌株的相对存活率分别为 73% 和 88%。这是第一个已知的关于南方水霉 RF Elliott 1968 在 C. gibelio (Bloch, 1782) 卵中感染的报告，涉及筛选作为潜在抗水霉剂的 R. sanguisorbae 提取物。