• Journal of Aquaculture
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• v.13 no.3
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• pp.239-244
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• 2000

To test survival growth of juvenile abalone, five different diet were constituted. Diet 1, the control, was constituted with white fish meal (15%), soybean meal (25%) and wheat flour (25%); diets 2,3 and 4 were constituted to replace each one of these ingradietns by supplementing Sargossum powder (upto 10 %) and the fifth one by Undularia powder. Survival of these abalones differed significantly. Diet 4 supported the fastest growth. There was no significant difference in the composition of these abalones hence Sargassum can be used as a substitute.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.41 no.6
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• pp.466-470
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• 2008

Microsatellite DNA markers were used to investigate the genetic diversity and population structure of Pacific abalone Haliotis discus hannai collected from six locations (Uljin, Ulsan, Daechon, Taean, Wando, and Yosu) where hatchery-produced abalone have been released intensively. There was no distinguishable difference in the observed and expected heterozygosities between the six populations and a cultured population. However, there was a difference in the number of alleles per locus: 12.8 for the cultured population and 13.8 to 15.8 for the six populations. The proportion of stocked abalone ranged from 41.1 to 92.7% for wild-caught populations with a decreasing tendency of alleles per locus for an increasing proportion of stocked abalone. A departure from Hardy-Weinberg equilibrium (HWE) assessed using the Markov chain procedure (P<0.05) was observed in the six populations and cultured population at loci Hdh145 and Hdh5l2. The pairwise Fst test (P<0.05) showed a significant difference between the Uljin and Ulsan populations and four remaining populations (Wando, Daechon, Yosu, and the cultured population), among which the Wando population differed less than the other three populations (Daechon, Yosu, and the cultured population).

• Journal of Marine Bioscience and Biotechnology
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• v.2 no.2
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• pp.108-112
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• 2007

A cellulase (endo-${\beta}$-1,4-D-glucanase(E.C.3.2.1.4)) was isolated from the hepatopancreas of abalone Haliotis discus hannai by EST analysis. The abalone cellulase named HdEG compassed 1977 bp, including 195 bp in the 5'untranslated region, 1680 bp in the open reading frame which encodes 560 amino acid residues, and 92 bp in the 3'-untranslated region. The C-terminal region of the HdEG showed 44-52% identity to the catalytic domains of glycoside hydrolase family 9 (GHF9)-cellulases from arthropods and bacteria. The recombinant cellulase, pEHdEG was produced in E. coli with being fused with C-terminal His-tag. The expressed protein showed a single band (~62 kDa) on Western blotting which was consistent with the value (61,878 Da) calculated from the DNA sequence.

• Fisheries and Aquatic Sciences
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• v.24 no.12
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• pp.400-405
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• 2021

In this study, the relationship between the growth of abalone and the presence of epibionts was investigated in abalone cultured in Goheung, Jeollanam-do, where there are severe problems high water temperatures and attachment. The experiment was conducted for eight months (May-December 2020), and 40 abalone were collected every month. Water temperature was at its highest at a range of 13.5℃-26.6℃ and dissolved oxygen levels were at their lowest at a range of 4.0-10.2 ㎍/L in August. The shell height (mm) of abalone grew to 117.7% (81.8 ± 1.9 mm) in cultures where epibionts were removed (ER) and 111% (77.4 ± 3.3 mm) where they were not (non-epibionts, NER). Their total weight (TW) and body weight increased significantly and steadily with ER, whereas the TW increased sharply after August with NER. In the condition index, no significant difference was observed between ER and NER. The monthly proportion of epibionts increased significantly in July, accounting for the value of 69.9% reached in December.

• Development and Reproduction
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• v.18 no.1
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• pp.43-49
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• 2014

Three species of Nortamea concinua (NC) and Haliotis discus hannai (HDH) from Tongyeong and Sulculus diversicolor supertexta (SDS) are widely distributed on the coast of the Yellow Sea, southern sea and Jeju Island in the Korean Peninsula under the innate ecosystem. There is a need to understand the genetic traits and composition of three mollusk species in order to evaluate exactly the patent genetic effect. PCR analysis was performed on DNA samples extracted from a total of 21 individuals using seven decamer oligonucleotides primers. Seven primers were shown to generate the unique shared loci to each species and shared loci by the three species which could be clearly scored. A hierarchical clustering tree was constructed using similarity matrices to generate a dendrogram, which was facilitated by the Systat version 10. 236 specific loci, with an average of 56.3 per primer, were identified in the NC species. 142 specific loci, with an average of 44.7 per primer, were identified in the HDH species. Especially, 126 numbers of shared loci by the three species, with an average of 18 per primer, were observed among the three species. Especially, the decamer primer BION-75 generated 7 unique loci to each species, which were identifying each species, in 700 bp NC species. Interestingly, the primer BION-50detected 42 shared loci by the three species, major and/or minor fragments of sizes 100 bp and 150 bp, respectively, which were identical in all samples. As regards average bandsharing value (BS) results, individuals from HDH species (0.772) exhibited higher bandsharing values than did individuals from NC species (0.655). In this study, the dendrogram obtained by the seven decamer primers indicates three genetic clusters: cluster 1 (CONCINNA 01~CONCINNA 07), cluster 2 (HANNAI 08~HANNAI 14), cluster 3 (SUPERTEXTA 15~SUPERTEXTA 21). Comparatively, individuals of HDH species were fairly closely related to that of SDS species, as shown in the hierarchical dendrogram of genetic distances.

• Journal of Life Science
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• v.19 no.8
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• pp.1003-1008
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• 2009

Abalone (genus Haliotis) is a woody species with a long life span that is primarily distributed throughout the world, including Asia. This species is regarded as a very important marine gastropod mollusk in Korea and China, and also in food industries around the world. We evaluated a representative sample of the five species with nuclear ribosomal DNA internal transcribed spacer sequences (ITS) to estimate genetic relationships within the genus. Aligned nucleotide sequences of the length of the 5.8S subunit of all taxa of Haliotis were found to constant of 160 bp nucleotides. However, aligned nucleotide sequences of the length of ITS1 were varied within genus Haliotis, varying from 272 in H. diversicolor aquatilis to 292 in H. discus hannai. Aligned nucleotide sequences of the length of ITS2, especially, vary from 722 in H. diversicolor aquatilis to 752 in H. sieboldii. Total alignment length is 763 positions, of which 78 are parsimony-informative, 57 variable but parsimony-uninformative, and 459 constant characters. H. discus hannai was similar to H. discus, while H. diversicolor aquatilis was more distinct. ITS analysis may be useful in germ-plasm classification several taxa of genus Haliotis.

• The Korean Journal of Malacology
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• v.30 no.3
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• pp.219-226
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• 2014

The effects of different stocking densities on the growth and survival rate of the abalone, Haliotis discus hannai, were investigated in marine net cage for two years. Stocking density was set 15, 30, 45 and 60 percentage $(=per.)/m^2$ with share to cross-sectional area per shelter. The primary rearing period (PRP) and the secondary rearing period (SRP) were conducted by a year. One year mean water temperature of PRP and SRS showed the difference about $2^{\circ}C$. In the growth (initial mean shell length of abalone : $36.14{\pm}2.28mm$) of PRP, the absolute growth rate (ARG), daily growth rate (DGR) and specific growth rate (SGR) of the $15per./m^2$ were higher than those of density groups (P < 0.05). Survival rates of all density groups were showed no significant difference. In the growth (mean shell length of abalone : $55.26{\pm}6.93mm$) of SRP, ARG, DGR and SGR of stocking density groups showed no significant difference except for $45per./m^2$ density group. Survival rate in the low-density (15, $30per./m^2$) was more than 70%, and those of the high-density (45, $60per./m^2$) were less than 31% and 9%, respectively. These results showed that the appropriate stocking density for $15per./m^2$ was seven hundred fifty number per one net cage ($2.4{\times}2.4m$), during PRP using 3-4 cm abalone in length. Also for the secondary rearing period, the optimal stocking density (shell length 5-6 cm of abalone) consider with the economical efficiency was determined to be $30per./m^2$, resulting the productivity improved.

• Journal of Aquaculture
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• v.13 no.1
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• pp.55-62
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• 2000

A 10-week feeding trial was conducted to investigate the effects of several yeasts with or without chemical treatment (protoplasted) in formulated diets on growth and body composition of juvenile abalone(Haliotis discus hanai). There replicate groups of the abalone average weighing 210 mg were fed one of eight isonitrogenous (30%) and isolipidic (4.4%) diets containing 3% Kluyveromyces fragilis protoplasted K. fragilis Candida utilis protoplasted C. utilis, Saccharomyces cerevisiae protoplasted S. cerevisiae or brewer's yeast. In addition these formulated diets were compared with commercial diet. Survival rate and proximate analysis of soft whole body of abalone were not significantly affected by the different dietary yeasts and commercial diet (P>0.05) Body weight gain and soft body weight control diet and diets containing S. cerevisiae or brewer's yeast (P<0.05) Shell length of abalone fed yeast and commercial diet (P<0.05) Th results suggest that protoplasted K. fragilis as an additive in this formulated diet can improve weight gain of abalone.

• The Korean Journal of Malacology
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• v.29 no.4
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• pp.303-311
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• 2013

This study investigated survival, falling and structural changes of foot in Haliotis discus hannai with various water temperature and salinity. Experimental conditions were composed of control with $20^{\circ}C/33.5$ psu, higher temperature group with 23, 26, 29 and $32^{\circ}C$, lower temperature group with 3, 6, 9 and $12^{\circ}C$, and different salinities group with 33.5, 26.8, 20.1, 13.4, 6.7 and 3.3 psu. Experimental period was 7 days. Survival and falling rate of the abalone exposed to 7 days at control and experimental condition of $12^{\circ}C$ and $23^{\circ}C/33.5$ psu were 100% and 0%, respectively. Mortality and falling rate of the abalone exposed to the different temperature and salinity were dose dependent by experimental condition. Histopathological changes in epithelial and muscular layer of foot showed more obvious with experimental condition of salinity decrease than different temperature condition.

• Proceedings of the Korean Society of Developmental Biology Conference
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• 2003.10a
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• pp.74-74
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• 2003

In present study, attempts were made to preserve abalone (Haliotis discus hannai) sperm in liquid form at low temperature, to evaluate the effect of various diluents in short-term storage on sperm, and cryopreservation procedures were optimized for the cryoprotectants as well as freezing rates, in terms of the motility and survival rate, and the ultrastructural changes of sperm after short-term storage and cryopreservation were observed. The abalone sperm reached maximum motility until about 4min after activation. The motility was constant for about 16min, after which it dropped gradually, and about 50min later all motility ceased. Threshold activation of sperm was found in 40% artificial seawater (ASW), and motility increased as the concentration of ASW increased. In Hanks balanced salt solution without calcium (Ca-Free HBSS, 300 and 400 mOsmol/kg) and 10%, 20%, and 30% ASW the sperm was immotile, and motility once again restored incompletely only in HBSS of 300 and 400 mOsmol/kg, 20% and 30% ASW after 100% ASW was added. Sperm motility was extended following 20 days of cold storage only in 70% and 100% ASW. A high motility index of 3.5-4.5 was observed for the first 8 days in 70% and 80% ASW. In other diluents sperm motility was constant less than 10 days, and the motility index was obviously lower than that of sperm in 70% and 100% ASW. After 20 days of cold storage survival rates of 10.2%-20.7% were obtained in ASW and 300 mOsmol/kg HBSS, and that in 400 HBSS (65.3%) was significantly higher than others. The constant period of sperm motility stored in 70% ASW was longer obviously than that in 100% ASW after 6 days of storage, and the time to maximum motility of sperm stored in 70% increased gradually, while the difference in which of sperm in 100% ASW was not significant. The sperm plunged into liquid nitrogen all died except that sperm using 15% glycerol as cryoprotectant restored 10.4% of motility. The highest motility index (3.4) was obtained with 5% glycerol and freezing procedure: $50^{\circ}C$/min from $20^{\circ}C$ to $-80^{\circ}C$.