• Journal of Marine Life Science
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• v.7 no.1
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• pp.29-36
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• 2022

Sea cucumber, Aposticopus japonicus, is a major invertebrate species in the coastal regions of Korea. To evaluate the short-term stress levels according to the releasing methods, this study investigated the gene expression profiles of heat shock protein 90 (HSP90) by real-time quantitative polymerase chain reaction. When the juvenile sea cucumbers were packed in the vinyl bag with oxygen followed by transportation for 30 min or air-exposed for 1 h, the HSP90 gene expression levels in the experimental groups were significantly increased compared to those of the control groups (transported group, p=0.001; air-exposed group, p=0.032). The experimental group at 6 h post-release by seed-spreading method and at 2~6 h post-release by underwater hose-releasing method on board a fishing boat showed that the levels of HSP90 gene expression were not statistically significant but decreased slightly compared to the control group (seed-spreading group, p=0.069; hose-releasing group, p=0.093). On the other hand, the HSP90 gene expression showed an increasing pattern as the time passed (~6 h) after underwater release of juvenile sea cucumbers by divers (p=0.061). These results suggest that HSP90 gene expression can be used to investigate short-term stress response and effective releasing methods of juvenile sea cucumbers.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.50 no.5
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• pp.494-499
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• 2017

This study evaluated the abundance of fecal coliforms in oysters Crassostrea gigas, sea squirts Halocynthia roretzi and sea cucumbers Apostichopus japonicus in fisheries along the coast of Korea in 2014, and investigated the prevalence of antimicrobial resistance in Escherichia coli isolated from these fishery products. The ranges of fecal coliforms found in oysters, sea squirts and sea cucumbers were <18-20, <18-330 and <18-3,300 MPN (most probable number)/100 g, respectively. Sea squirts contained the greatest range of E. coli (<20-140 MPN/100 g), followed by sea cucumbers (<20-130 MPN/100 g) and oysters (<20-20 MPN/100 g). A total of 26 strains of E. coli were isolated from 34 sea squirt, 25 sea cucumber and 13 oyster samples. Strains thus isolated were tested for their susceptibility to 22 antimicrobial agents used in Korea for medical or veterinary therapy. E. coli isolates showed the greatest resistance to ampicillin (84.6%), followed by trimethoprim (34.6%), nalidixic acid (34.6%), tetracycline (30.8%), pipemidic acid (26.9%), streptomycin (23.1%), chloramphenicol (23.1%), trimethoprim/sulfamethoxazole (23.1%), and gentamicin (15.4%). Resistance to at least one antimicrobial agent was present in 88.5% of E. coli isolates. Of the 26 isolated, six strains (23.1%) were resistant to multiple antimicrobial agents.