• Applied Biological Chemistry
• /
• v.17 no.4
• /
• pp.257-274
• /
• 1974

The studies on the carotenoids in the viscera of abalone (Haliotis discus hannai) have been-carried out. The pigments were extracted with acetone-methanol mixture (4 : 1) from the viscera of abalones which were caught around the coastal water of Korea from March to August. The individual carotenoid in the extracts was separated and purified by the silica gel TLC, $Mg(OH)_2$ impregnated paper chromatography and $Mg_2(OH)_2CO_3$ TLC. The isolated eleven carotenoids were investigated and identified by epoxide test, partition test, reduction with sodium borohydride, alkaline hydrolysis, co-chromatography and comparative test with reference carotenoids and electronic and IR absorption spectrophotometry. ${\alpha}$-Carotene, ${\beta}$-carotene. lutein, zeaxanthin, siponaxanthin, siponein, fucoxanthin, loroxan-thin-like and fucoxanthinol-like have been identified among the eleven carotenoids isolated. It has been found that fucoxanthin, on alkaline treatment, was transformed to the product of which chromophore was the same one as fucochrome and semifucoxanthol. Among the identified nein carotenoids siphonaxanthin, siponein, fucoxanthin, loroxanthin-like and fucoxanthinol-like have not been reported previously to be contained in the shellfish.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.8 no.4
• /
• pp.234-241
• /
• 1975

Reproductive cycle of Haliotis discus hannai Ino was studied based on the samples which were collected in Yeosu area from January, 1973 to December, 1974. Particular emphasis was paid on the seasonal variation of gonad maturity factor, coefficieot of gonad maturity, fatnesss, and relationship of gonad weight to growth of the abalone. seasonal fluctuation of water temperature and induction of artificial spawnings were also checked. The abalone of this area spawns twice a year: spring spawning(early May-late July) and Autumn spawning(early September-late November). peak spawning occurs from late May to middle of June for spring spawning: it occurs from late September to early November for Autumn spawning. Gonad maturity factor was closely related to the spawning seasons. For the spring spawning Gonad maturity factor reached to its maximum value as 18.84 in April; for the Autumn spawning it reached to its maximum value as 22.65 in September. Annual minimum value was 12.65 in January. Annual maximum values of coefficient of gonad maturity were 44.10 in May and 49.05 in September and the annual minimum was 10.09 in January. Fatnesswas highest in July as 0.221 and it was lowest in October as 0.1058. Ratios of shell length to gonad weight were formulated as follows : $$In\;September\;GW=0.000003710SL^{3.7860}$$ $$In\;January\;GW=0.000021198SL^{2.8564}$$ $$Annual\;mean\;GW=0.00000005013SL^{4.2273}$$ Relations of total weight to gonad weight were formulated as follows : In September GW=0.1918TW-4.9231 In January GW=0.0992TW-0.1759 Annual maan GW=0.1568UW-3.5256.

• Journal of Aquaculture
• /
• v.16 no.4
• /
• pp.257-261
• /
• 2003

The effects of different stocking densities on the growth of juvenile abalone, Haliotis discus hannai and water quality in the recirculating system with rotating biological contactor, were assessed. The trials were conducted using total weight 32 g juveniles abalone for 60 days at stocking densities of 5, 10, 15 kg/$m^2$. The animals were fed sufficient amounts of the pellet diet of 30.4% protein during the experimental period. Daily feeding rate (DFR) and survival rate (SR) of 5 kg/$m^2$ showed 0.76% and 85.5% those were not significantly differed 10 kg/$m^2$ showing 0.75% and 96.0% (P>0.05). DFR and SR of 15 kg/$m^2$ showing 0.38% and 31.2% were significantly lower than 5 and 10 kg/m2 (P<0.05). Daily growth rate (DGR) and feed efficiency (FE) showed the highest as 0.19% and 24.2% in 5 kg/$m^2$ the lowest as 0.05% and 14.3% in 15 kg/$m^2$ (P<0.05). According to, these results was an inverse relationship between growth and stocking density. The optimum density of juvenile abalone from this experiment is 5 to 10 kg/$m^2$ in the recirculating system.

• The Korean Journal of Malacology
• /
• v.26 no.2
• /
• pp.157-163
• /
• 2010

This study was carried out to investigate the toxic effect of WSF (Water Soluble Fraction) on development time, development rate, attachment rate, survival rate and growth of the larvae during the early life stage of the abalone, Haliotis discus hannai. Also, observed effect of water temperature on the survival rate and histological change of gill in the early young shell. In the abalone, it takes around 12 hours in all experimental groups. Development and attachment rate of the abalone significantly lower more than 0.4 mg/L WSF compared to control group (P < 0.05). Survival rate of abalone larva and spot was significantly lower more than 0.4 mg/L and 2.4 mg/L WSF compared to control group, respectively (P < 0.05). Shell growth of the abalone were significantly lower more than 2.4 mg/L WSF compared control group (P < 0.05). Survival rate lower more than $25^{\circ}C$ exposure group compared water temperature $17^{\circ}C$ exposure group in the early young shell. The gill of abalone exposed water temperature $17^{\circ}C$ and $25^{\circ}C$ was showed atrophy of nucleus and breakdown of the filament, vacuolation of filament epithelial cell.

• Journal of Life Science
• /
• v.19 no.8
• /
• pp.1003-1008
• /
• 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
• /
• v.30 no.1
• /
• pp.87-93
• /
• 2014

The Morphological characteristics of four species of Korean Abalone species, Nordotis discus hannai, N. discus discus, N. gigantea, N. madaka were compared. then Phenotypic traits were characterized. we collected from coast of samchonpo, sacjon-si, Gyeongsangnam-do and jeju-do of korea 69 individual of Nordotis discus hannai from 2013 December to 2014 January, 180 individual of N. discus, 72 individual of N. gigantea and 54 individual of N. madaka respectively then morphological traits of theses species characteristics were compared. The relationship between Shell length (SL), shell breth (SB), shell height (SH) and total weigh (TW) was expressed by the following equation: SB = 0.6346SL + 3.9082 ($R^2$ = 0.8956), SH = 0.2399SL + 3.2609 ($R^2$ = 0.8024), $TW=0.0009SL^{2.5622}$ ($R^2$ = 0.8088) in the Haliotis discus hannai, SB = 0.7249SL + 1.8035 ($R^2$ = 0.9634), SH = 0.3115SL - 11.223 ($R^2$ = 0.8593), $TW=0.0001SL^{2.9696}$ ($R^2$ = 0.8956) in the H. discus discus, SB = 0.7730SL - 1.1931 ($R^2$ = 0.933), SH = 0.2082SL + 3.2627 ($R^2$ = 0.6927), $TW=0.0002SL^{2.8330}$ ($R^2$ = 0.8431) in the Haliotis gigantea, SB = 0.7513SL - 1.0951 ($R^2$ = 0.913), SH = 0.2618SL - 6.1538 ($R^2$ = 0.6927), $TW=0.0001SL^{2.9614}$ ($R^2$ = 0.9353) in the Haliotis madaka.

• Proceedings of the Korean Aquaculture Society Conference
• /
• 2003.10a
• /
• pp.29-29
• /
• 2003

In order to establish effective procedures for chromosome manipulation in Haliotis gigantea and H. discus, which are of enormous aquacultural potential, temperature-dependent measures of mitotic intervals ($\tau$$_{0}$) were determined. Mitotic intervals ($\tau$$_{0}$) in these abalone were determined by averaging the duration of the first and third embryonic divisions over a range of temperatures from 8 to 26$^{\circ}C$. The relationships of each mitotic interval at two cell ($\tau$$_{I}$), four cell ($\tau$$_{II}$ ), eight cell ($\tau$$_{III}$), sixteen cell ($\tau$$_{IV}$ ) and $\tau$$_{0}$, to temperature (T in $^{\circ}C$) in H. gigantea were log $\tau$$_{I}$ : 176.1-28.3T, log $\tau$$_{II}$ : 199.5-12.4T, log $\tau$$_{III}$ = 236.2-12.2T, log $\tau$$_{IV}$ = 269.3-14.lT and log $\tau$$_{0}$ : 83.1-32.8, respectively. The relationships of each mitotic interval at $\tau$$_{I}$, $\tau$$_{II}$ , $\tau$$_{III}$, $\tau$$_{IV}$ and $\tau$$_{0}$, to temperature in H. discus were log $\tau$$_{I}$ = 104.9-13.8T, log $\tau$$_{II}$ : 138.3-10.5T, $\tau$$_{III}$ : 172.4-10.2T, log $\tau$$_{IV}$ : 211.3-12.2T and log $\tau$$_{0}$=85.6-33.3T, respectively. There were strong, negative correlations between mitotic interval and water temperatures for all ten temperatures in these two species (H. gigantea: Y = -138.75 logX + 341.25, $R^2$ = 0.97; H. discus: Y = -112.33 logX + 255.22, $R^2$ = 0.98, where Y is mitotic interval and X is temperature).d X is temperature).rature).

• Journal of fish pathology
• /
• v.26 no.3
• /
• pp.139-148
• /
• 2013

The genus Polydora(Polychaeta, Spionidae) includes many species well known for their activity as borers. They often become harmful invaders by reducing the growth rate and meat yield of, or inducing the mortality of commercially important mollusck, abalone, Haiotis discus hannai. In 2012, the frequency of the Polydora was observed with 5~99% in live abalone and 5.3~70.3% in dead abalone shells of abalone sea-caged aquaculture system, Korea. There are many nacreous blister in the ventral margin and inner of the infestated abalone by abalone in response to the Polydora. A worm bored two holes in the shell and come in and out for ingestion the organic matters. They are more than 40 mm in length and had outstanding palps with black bars, disc form pygidium and 4 eyespots. This is the first record for the statue of Polydora infestation of sea-caged cultured abalone, Haliotis discus hannai in Korea.

• Journal of Animal Reproduction and Biotechnology
• /
• v.35 no.3
• /
• pp.223-231
• /
• 2020

Karyotype analysis is a major work in the process of triploid abalone production for the purpose of productivity and quality improvement. However, the metaphase spreads for karyotype analysis have been prepared just from the larvae at trochophore stage, which has restricted the spectrum of sample correction inhibiting more efficient analysis. Here, we investigated the feasibility of preparing metaphase spreads from the larvae at veliger stage that is the next developmental stage of trochophore. For this, diploid and triploid larvae at trochophore and veliger stages from Pacific abalone (Haliotis discus hannai) were subjected to metaphase spread preparation and its efficiencies were measured and compared each other. As the results, although the efficiencies of metaphase spread preparation were significantly lower in the larvae at veliger stage compared to the ones at trochophore stage regardless of ploidy status, we found that the preparation of metaphase spreads, which showed the clear chromosomal images containing the normal number of chromosomes, was possible from the veliger stage larvae. On the other hands, all larvae used in this study regardless of developmental stage and ploidy did not show colchicine sensitivity. Moreover, no significant difference was observed in cell cycle distribution of the cells comprising larvae between two developmental stages regardless of ploidy status. These suggested that the details of protocol to prepare metaphase spreads from abalone larvae should be optimized depending on its developmental stages. Taken together, we demonstrated the feasibility of preparing metaphase spreads from H. discus hannai veliger stage larvae for karyotype analysis.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.40 no.3
• /
• pp.133-140
• /
• 2007

In 2006, we studied herbivore consumption rate and preference for algal species using laboratory experiments. In the no-choice feeding experiment, three herbivores (two sea urchins, Stronglyocentrotus nudus and Stronglyocentrotus intermedius and an abalone, Haliotis discus hannai) showed significantly (P<0.05) distinct preferences for four algae (Laminaria japonica, Undaria pinnatifida, Costaria costata and Ecklonia stolonifera). The alga preferred by S. nudus was L. japonica followed by U. pinnatifida, C. costata and E. stolonifera with respective daily feeding rates of $5.7{\pm}:0.85\;g,\;4.4{\pm}0.89\;g,\;3.1{\pm}0.39\;g\;and\;2.1{\pm}0.32\;g(mean{\pm}SE)$. A similar trend was found for S. intermedius. Interestingly, the herbivore consumption rates for the algae differed with or without competition. The competition stimulated the feeding activity for S. nudus, but lowered the activity for S. intermedius. The multi-choice feeding experiment confirmed that L. japonica was significantly preferred by two herbivores: S. nudus and H. discus hannai (Duncan's multiple range test, ANOVA, p<0.05).