South Australian Research and Development Institute (SARDI), Seafood Safety and Market Access, 2B Hartley Grove, Urrbrae, 5064, Australia; Institute for Marine and Antarctic Studies, University of Tasmania, 20 Castray Esplanade, Hobart, Tasmania, 7001, Australia.
Institute for Marine and Antarctic Studies, University of Tasmania, 20 Castray Esplanade, Hobart, Tasmania, 7001, Australia.
Harmful Algae. 2020 Nov;99:101925. doi: 10.1016/j.hal.2020.101925. Epub 2020 Oct 27.
The Tasmanian abalone fishery represents the largest wild abalone resource in the world, supplying close to 25% of the annual wild-caught global harvest. Prompted by the need to manage Paralytic Shellfish Toxin (PST) contamination of Blacklip Abalone (Haliotis rubra rubra) from east coast Tasmania, the uptake of toxins by this species is investigated in a land-based, controlled aquaculture setting. Abalone were exposed to either live Alexandrium catenella microalgal cultures or PST contaminated feed pellets during a 28 day exposure period and toxins quantified in viscera, foot muscle and epipodium tissues. PST profiles of abalone foot tissues were dominated by saxitoxin and neosaxitoxin, whilst viscera more closely resembled those of the toxin source (A. catenella cells rich in gonyautoxin 1&4 and 2&3 or feed pellets containing A. catenella extracts rich in these analogues). This indicates direct uptake of PST in the viscera via browsing/grazing on the pellet and /or sedimented microalgal cells. After exposure to A. catenella cell culture, PST concentrations in the foot (muscle + epipodium) were on average 8 times higher than in the viscera. Higher toxicity of foot tissue was caused by higher PST content of the epipodium (up to 1,085 µg STX.2HCl equiv. kg), which despite its small contribution to total animal weight significantly added to the overall toxin burden. Higher PST levels in the abalone foot suggest that toxin monitoring programmes may not need to routinely analyse both foot and viscera, potentially allowing for a 50% reduction of analytical costs. This option is being further investigated with continuing field studies.
塔斯马尼亚鲍鱼渔业是世界上最大的野生鲍鱼资源，供应了近 25%的全球野生捕捞量。由于需要管理东海岸塔斯马尼亚黑唇鲍（Haliotis rubra rubra）中的麻痹性贝类毒素（PST）污染，因此在陆基控制水产养殖环境中研究了该物种对毒素的吸收。在 28 天的暴露期内，鲍鱼暴露于活亚历山大藻（Alexandrium catenella）微藻培养物或 PST 污染的饲料颗粒中，并在内脏、足部肌肉和上足组织中定量毒素。鲍鱼足部组织的 PST 图谱主要由石房蛤毒素和 neo 石房蛤毒素组成，而内脏则更类似于毒素源（富含 GTX1&4 和 2&3 的 A. catenella 细胞或富含这些类似物的 A. catenella 提取物的饲料颗粒）。这表明通过对颗粒和/或沉降微藻细胞的啃食/放牧直接在内脏中吸收 PST。暴露于亚历山大藻细胞培养物后，足部（肌肉+上足）中的 PST 浓度平均比内脏高 8 倍。足部组织的毒性更高是由于上足（epipodium）中的 PST 含量更高（高达 1,085 µg STX.2HCl equiv. kg），尽管其对总动物体重的贡献很小，但却显著增加了总毒素负担。鲍鱼足部的 PST 水平较高表明，毒素监测计划可能不需要常规分析足部和内脏组织，这可能使分析成本降低 50%。正在通过持续的实地研究进一步研究这一选择。
