Abstract
Cetacean bycatch has been increasing with modern fisheries, and animals caught have been utilized for consumption.1 Additionally, illegal whaling for various uses like bait or human consumption has been found in many countries.2 The scale of exploitation remains unclear, posing a potential threat to the sustainability of certain species, especially baleen whales, which have suffered from commercial whaling in the past.2,3 In addition to these concerns, public health has been put at risk due to the high contamination level and zoonotic pathogens associated with the consumption of cetacean-based food products.4,5 Previously, PCR, with sequencing and rapid immunoassay, was provided as tools for cetacean identification, but there existed several limitations, like demands for laboratory equipment, trained analysts, and fresh samples. We developed a portable detection toolset to identify cetacean meat and other tissues based on recombinase polymerase amplification (RPA) with dual lateral flow strip (LF). The DNA crudely extracted from cetacean samples was amplified by two pairs of specific primers based on its mitochondrial control region, with one targeting sequences of all cetacean species and the other targeting only sequences of baleen whales. The DNA was amplified for 10 minutes at a constant temperature ranging from 30–40°C using RPA. The amplification products were then visualized on the dual LF strip within five minutes. A double positive result indicated that the inspected meat product belonged to baleen whales, while a single positive result implied that it belonged to toothed whales. The whole examination process, from quick DNA extraction to LF visualization, took approximately 30 minutes. Compared with protein-based immunoassay, this RPA-LF assay was also effective when using boiled and pan-fried samples. With this portable and accessible detection tool set, inspecting suspicious cetacean products may become more efficient and facilitate the implementation of an extensive field survey. Moreover, it can improve our understanding of the pathway of illegal trade and consumption of cetacean products. A more comprehensive understanding of cetacean consumption is essential for establishing feasible management policies aimed at certain vulnerable species.
Acknowledgments
We would like to thank all previous researchers devoted to cetacean sample collection and preservation. This study was supported by Ocean Conservation Administration, Ocean Affairs Council, Taiwan.
*Presenting author
+Student presenter
Literature Cited
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