• Journal of Environmental Health Sciences
• /
• v.23 no.1
• /
• pp.14-17
• /
• 1997

A total of 93 specimens of Astroconger myriaster were purchased from the Chungmu fishery market at the south sea area during the period from October 1 to November 25, 1996. Specimens were examined for the infection status with larvae anisakid. Anisakid larvae were collected from viscera, muscle, omenturn and liver. Eight hundred four larval anisakids sorted from 93 specimens of A. myriaster ranged from 9.0 to 26.5mm in their body length. They were classified based on morphological and morphometric observations as follows Anisakis type 1 larvae (465 larvae, 57.8%: positive rate), Contracaecum type D(129, 16.0%), Contracaecum type A(90, 11.2%), Anisakis type 11(60, 7.5%), Phapidascaris(3, 0.4%) and unknown type(57, 7.1%).

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.37 no.6
• /
• pp.492-497
• /
• 2004

Waste concentration and waste generation rate in seawater aquaria by common conger (Astrocongey myriaster) and olive flounder (Paralichyhus olivaceus) were investigated. The initial fish density of common conger and olive flounder were $3{\%}\;and \;2.8{\%}$ of total weight of aquarium water, respectively Wastes in the seawater aquaria, such as protein, total suspended solid (TSS), ammonia, turbidity and chemical oxygen demand (COD) increased with days after stocking. Protein generation rate of common conger increased until 1 day after stocking while that of olive flounder increased until 3 days. The average protein generation rates of common conger and olive flounder were $0.28g/kg{\cdot}day\;and\;0.21g/kg{\cdot}day$, respectively. The trends of other waste generation rate were similar to protein generation rate.

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.28 no.4
• /
• pp.380-384
• /
• 1992

The authors carried out an experimental fishing of Sea eel(Astroconger Myriaster) Pots to find the accuracy of the relationship formula between body dimensions and the optimum diameter of pot hole. The diameter of pot hole was used by an experimental fishing were 0.7, 0.9, 1.0, 1.5, 2.0cm. the number of pot were 271, 278, 283, 296 respectively. An experimental fishing was performed during October, 1988 in the southern Sea of Korea. The results obtained can be summarized as follows; 1. The relationship formula between body dimensions was very accurate. 2. Optimum diameter of pot hole must be made 1.5cm at least.

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.23 no.4
• /
• pp.184-188
• /
• 1987

The author studied to analyse the relationship between the body dimension of sea eel, Astroconger myriaster and the mesh size of fishing gears. The samples were caught by traps and pots during September, 1987 in the Southern Sea of Korea. The results obtained can be summarized as follows: 1. The relationship between total length L, body weight W and diameter D may be expressed as: W=3.58$\times$10 super(-4) L super(3.38) (r=0.99). D=0.07 L-0.59 (r=0.99). W=10.38 D super(2.76) (r=1.00). W=1/2$\times$D super(2).L. 2. The mesh size of traps and the hole diameter of post must be more than 29.2 mm and 18.6 mm, respectively.

• Parasites, Hosts and Diseases
• /
• v.30 no.3
• /
• pp.157-162
• /
• 1992

Although the sea eel (Astroconger myriaster) is suspected as one of the most important fish host for human anisakiasis in Korea, no report has been made on the infection status of the sea eel with anisakid larvae. In the present study, 26 sea eels (Astroconger myriaster) were purchased from the Noryangjin 6sh market in Seoul, and anisakid larvae were collected from their viscera, muscle, head and skin. The collected larvae were classified by their morphological types. A total of 1,351 anisakid larvae were collected from 15 of 26 fish examined. Among them, 1,269 were recovered from the viscera, 66 from the muscle, and 16 from the head and skin. Morphologically, most of the anisakids were classified into 6 known larval types, Anisakis type I (564 larvae) of Berland(1961) , Contracaecum type A(409) and type D(5) of Koyama et at. (1969), Contracaecum type C'(83) and type D'(117) of Chai et at. (1986), and Contracaecum type V(1) of Yamaguti (1935). Remaining 172 specimens were new in the available literature, hence, designated as Centracaecum type A'(new type). The present results revealed that the sea eels caught in the Korean waters are heavily infected with anisakid larvae, not only in their viscera but also in the muscle, and Anisakis type I was the most common among the 7 larval types.

• Parasites, Hosts and Diseases
• /
• v.30 no.4
• /
• pp.263-268
• /
• 1992

A study was presented on the anisakid larvae in Astroconger myriaster which were caught at the Southern Sea and waled at Pusan area. The nematodes were morphologically classified into Anisakis sp. and Centracgecum sp. after fixation in 70% ethanol and clearing in lactophenol. Total of 1, 768 larval anisakids were collected from 259(67.8% positive rate) out of 382 examined A. myriaster. Total 642 larvae of Anisakis sp. were obtained from 94 (24.6%) and 1, 126 Ccntracaecum sp. were recovered from 165 (43.1%) fish. The average number of worms per infected fish was 4.6. The infection rate increased according to the length of fish, and all of the fish over 71 cm were found infected. The numbers (proportions) of recovered worms by the organs were 1, 440 (80.5%) in the omentuin, 166(9.4%) in the intestine, 107(6.0%) in the stomach, 32(1.8%) in the skin, 18(1.0%) in the muscle, 13(0.7%) in the liver, and 2(0.1%) in the head. The larvae in the muscle may infect the humans who are enjoying raw sliced meat of the fish.

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.26 no.4
• /
• pp.317-325
• /
• 1990

The attraction activity of the natural baits for sea eels(Astroconger myriaster) was surveyed by using fishing traps in the 3 different fishing ground of southern coastal waters of Korea. Twenty four different baits were experimented and weight for each bait was 50g, the optimal minimum weight owing to our preliminary test. Among the above 24 baits, anchovy(Engraulis japonica), sardine(Sardinops melanosticta), or marine worms(Neanthes japonica)were most effective. In case of sardine bait, the body showed higher attraction activity than the head or viscera and the builded juice of anchovy or sardine showed higher attraction activity than spoiled one.

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.26 no.4
• /
• pp.326-332
• /
• 1990

The chemical attractants for sea eels, Astroconger myriaster, were identified by using fish traps in their natural habitat around namhae island, southern part of Korea. The ethyl alcohol extracts of anchovy, Engraulis japonica, which was a very good baits for sea eels showed higher attraction activities than residuals of it. Because sea eels showed high attraction activities to the free amino acid or nucleotides of synthetic anchovy extract, the succeeding experiment was conducted to identify the major chemical attractants among 9 free amino acid and 2 nucleotides by omission test. L-Glutamic acid, L-glycine, taurine, L-methionine or IMP showed highest attraction activities among 11 chemical compounds. But sea eels showed significantly weaker attraction activities to the synthethic extracts and single component than to the natural extract.

• Parasites, Hosts and Diseases
• /
• v.53 no.3
• /
• pp.349-353
• /
• 2015

Anisakis simplex sensu stricto (s.s.), Anisakis pegreffii, Anisakis berlandi (=A. simplex sp. C), and Anisakis typica are the 4 major species of Anisakis type I larvae. In the Republic of Korea (Korea), A. pegreffii, A. berlandi, and A. typica larvae in fish hosts has seldom been documented. In this study, molecular analysis was performed on Anisakis larvae from the sea eels (Astroconger myriaster), the major source of human anisakiasis in Korea, collected from Tongyeong City, a southern coastal area of Korea. All 20 sea eels examined were infected with Anisakis type I larvae (160 larvae; 8 per fish). Their species were analyzed using PCR-RFLP patterns and nucleotide sequences of internal transcribed spacers (ITS1, 5.8 subunit gene, and ITS2) and mitochondrial cytochrome c oxidase 2 (cox2). Most (86.8%; 112/129) of the Anisakis type I larvae were A. pegreffii, and 7.8% (10/129) were A. typica. The remaining 5.4% (7/129) was not identified. Thus, A. pegreffii is the major species of anisakid larvae in sea eels of the southern coast of Korea.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.17 no.1
• /
• pp.15-23
• /
• 1984

Difference of the entering and the escaping behaviour of shrimp(Palaemon pacificus) to the model traps were observed in accordance with netting materials, baits, type of traps and slope of flapper, and gathering responses were also investigated on the odour of bait extracts in the aquarium as the preliminary test. In order to investigate the difference in catch according to type and structure of traps those designated from A to E were made of iron frames and nettings. The type A was a conical shape with two entrances at its both sides and the others were square piller shape with one entrance at their upper surface(type B) or two entrance at their both ends(type C, D and E). However th type D and E were connected with flapper and the thye E was made by attaching iron frames of same height under the type D. The traps were prepared 10 each and so a total of 50 traps were used in the experiment at sea. The main species caught was Charybdis japonica, but Astroconger myriaster was also caught fairly. The catches of these species were significant in difference between the types of traps. That is, Charybdis japonica was caught more in type A, C and D than others and less in type B and E, and Astroconger myriaster was caught more in type A and D and less in type B and E. However the catch of Astroconger myriaster in type C, even if less than that in type A showed no significant difference with the other traps. The total catch of Charybdis japonica and Astroconger myriaster was almost same in order with the catch of Charybdis japonica. The type B and E seemed to be difficult in entering of fishes into them. However, the type A and C seemed to be easy not only in entering, but also in escaping. Especially, the type C showed more escaping. On the other hand, the type D seemed to be not so easy in entering of fishes as type A and C, but very difficult in escaping. Consequently, the escaping of fishes from the traps seemed to be more difficult in conical traps than any other traps. The catches might be influenced by the bait with bag compare to without bag and also the immersed time of traps into water for fishing.