• The Korean Journal of Malacology
• /
• v.31 no.1
• /
• pp.1-8
• /
• 2015

This study was conducted to investigate the effects of elevated water temperature (WT) on biochemical and immunological factors in the hemolymph of the abalones, Haliotis discus hannai and H. discus discus. The abalone were exposed to various WT; 20, 22, 24, 26 and $28^{\circ}C$ for 4 days. In the control and $20^{\circ}C$, total-protein (TP), glucose and calcium (Ca) in hemolymph of H. discus discus were higher than the values in H. discus hannai. The values of magnesium (Mg), alkaline phosphatase (ALP) and lysozyme in H. discus hannai were similar to the H. discus discus in the control. There were no significant alterations in TP, glucose and Mg levels of hemolymph in H. discus hannai and H. discus discus by WT increases. The values of Ca, ALP and lysozyme were increased in H. discus hannai exposed to the high temperature (26 and $28^{\circ}C$) compared to control, while the values in H. discus discus were not significant difference between the WT groups. The phenoloxidase (PO) activity was increased in hemolymph of H. discus hannai exposed to high temperature (${\geq}24^{\circ}C$) compared to the control (P < 0.05). These physiological and immunological parameters were significantly changed in H. discus hannai. However, these parameters in H. discus discus were barely altered at the high WT (P < 0.05). These results suggested that H. discus hannai is considered to be more sensitive than H. discus discus at the high WT.

• The Korean Journal of Malacology
• /
• v.31 no.3
• /
• pp.187-194
• /
• 2015

This study was conducted to examine the effects of alterations in water temperature (WT) on biochemical and immunological factors in the hemolymph of the abalones, Haliotis gigantea and H. discus discus. The abalone were exposed to various WT; 18, 20, 22, 24, 26 and $28^{\circ}C$ for 96 hours. In biochemical factors, total-protein (TP), glucose, magnesium (Mg), aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were not significant changes in hemolymph of H. gigantea and H. discus discus. But calcium was significantly increased by high WT (${\geq}24^{\circ}C$). In immunological factor, The phenoloxidase (PO) activity was decreased in hemolymph of H. gigantea and H. discus discus exposed to high temperature (${\geq}22^{\circ}C$) compared to the control (P < 0.05). Whereas alkaline phosphatase (ALP) was not significantly changed. These results suggested that high temperature adversely affects the immunity of H. gigantea and H. discus discus.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.42 no.6
• /
• pp.591-599
• /
• 2009

Genetic parameters for growth-related traits were estimated in 9-month old of two Korean abalone subspecies, Haliotis discus hannai and H. discus discus, using multiple traits of animal model. The data were collected from the records of 3,504 individuals produced from 16 sires and 17 dams in H. discus hannai and 821 individuals produced from 3 sires and 4 dams in H. discus discus, which was evaluated at the Bukjeju branch, NFRDI, from May 20, 2004 to February 14, 2005. The heritability estimates obtained from restricted maximum likelihood (REML) method range from 0.29 to 0.31 for three growth traits (shell length, shell width and body weight) in H. discus hannai and from 0.22 to 0.28 in H. discus discus, respectively. The heritabilities for shell shape and condition factor were lower than others of growth traits such as ranging from 0.03 to 0.24 in H. discus hannai and from 0.06 to 0.11 in H. discus discus, respectively. Genetic and phenotypic correlations were >0.91 between shell parameters and weight in two abalone subspecies, respectively, indicating that breeding for weight gains could be successfully achieved by selecting for shell length.

• Journal of Aquaculture
• /
• v.21 no.4
• /
• pp.218-225
• /
• 2008

Changes in 13 free amino acids (FAA) of Haliotis discus discus exposed to various salinities were investigated using a high performance liquid chromatography (HPLC). Taurine, glycine and alanine are three major contributors to the total FAA in the gill tissues of H. discus discus. Concentration of taurine was 114 imol/g dry tissue weights accounting for 76.64% of total FAA in H. discus discus. Levels of most FAAs in H. discus discus exposed to low and high salinities for 24 h decreased dramatically. Taurine concentration was slightly increased in the samples exposed to 20 psu and 25 psu for 48 h, and greatly increased after 120 h exposure. After 48 hrs exposure to 20 psu, 25 psu, 30 psu and 40 psu, methionine in H. discus discus was not detected; no methionine was detected in the sample exposed to 20 psu, 25 psu, 30 psu and 40 psu after 120 h of exposure. Taurine:glycine ratio increased depending upon hyper-hypoosmotic condition as well as period of osmotic stress. These data indicate that taurine, glycine and methionine play important role in regulating osmotic stress in H. discus discus. This study suggesting that FAA analysis is a useful tool to diagnose osmotic stress to H. discus discus.

• ALGAE
• /
• v.22 no.3
• /
• pp.241-246
• /
• 2007

Cochtodinium votykrikoides -related red tide is the most notorious tidal bloom, resulting in mass mortality to marineanimals. This study aimed to test the effect of C. polyknkoides on the lethality to Haliotis discus hannai under con-trolled conditions. The oxygen demand of C. polykrikoides increases to reach its peak duhng the night, while the oxy-gen usage by H. discus hannai was continuously decreased with a threshold of 2 mg L U. The addition of C.polykrikoides did not effect the respiration of the H. discus hannai. However, the usage of oxygen by C. polykrikoidesduhng the night may lead to anoxia in the animal. With aeration, the level of dissolved oxygen (D.O.) was between6.06 and 7.28 mg LU; 90% of abalones survived even with a high concentration of C. potykrikoides (9000 cells mL U).Without aeration (3 mg LU of D.O.), however, the H. discus hannai suffocated immediately. Once 20 hours hadelapsed, all of the abalones were dead. The density of the H. discus hannai population contributed to their mortality.Therefore, aeration during the night and maintaining lower abalone densities is the best way to promote the sur-vivorship of H. discus hannai during a C. polykrikoides red tide.

• Journal of Marine Life Science
• /
• v.7 no.2
• /
• pp.163-170
• /
• 2022

In this study, the results of hybridization were evaluated by analyzing the biomarkers of Haliotis discus hannai and hybrid abalone (H. madaka♀^*H. discus discus♂) in marine net cage. The survival rate was similar both experimental groups, but the growth (shell length) was about 10% faster in hybrid abalone. The deformity of respiratory pore in the hybrid abalone was about 6% lower than H. discus hannai, and the shell depression was about 15% lower in the hybrid abalone. In the biochemical composition, crude protein was about 3.1% higher in hybrid abalone, and showed similar values except for the crude protein. In the histological structure of the hepatopancreas, which performs the functions of digestion, absorption and detoxification of abalone, good results were obtained in the hybrid abalone. On these results, it is judged that the hybrid abalone will have high aquaculture productivity in the aquaculture environment.

• Journal of Aquaculture
• /
• v.11 no.4
• /
• pp.505-512
• /
• 1998

This study was conducted to investigate the effects of three different formulated diets and macroalgae(Undaria) on growth and body comoposition among juvenile Haliotis discus, H. sieboldii and H. discus hannail. Three replicate groups among the three species abalones average weighing 0.31g were fed one of one experimental diet, two commercial diets and Undaria for 9 weeks. The three formulated diets produced significantly (P<0.05) greated body and shell growth than Undaria within same abalone species. Survival rates (97~99%) of H. discus and H. sieboldii were higher than that (74~77%) of H. discus hannai. Whereas different diets had no significantly (P>0.05) distincitive effect on survival within each three different abalone species. Moisture of abalone soft body in final stage reduced compared to those of abalone in initial stage in H. discus and H. discus hannai. Regardless of diet, abalone soft body revealed significantly (P<0.05) increased protein and decreased ash at the end of feeding trial in all three abalone species. This study indicate that all three different formulated diets used in this experiment could be a practical diet in three abalone species.

• The Korean Journal of Malacology
• /
• v.24 no.2
• /
• pp.121-130
• /
• 2008

In other aquaculture species, large improvements in growth have been achieved through selective breeding. Ezo abalone(Haliotis discus hannai) and disk abalone(H. discus discus) are major aquatic animals cultured in Asia, but selective breeding for the promotion of growth with these abalones has not been actively pursued. Recently significant efforts are being made to promote production of these species through selective breeding in Korea. The aims of this work were to estimate the general genetic parameters, heritabilities, and genetic and phenotypic correlations on growth-related traits at 1-year old in two Korean abalone subspecies, H. discus hannai and H. discus discus, by using multiple trait animal model. The data were collected from the records of 1,504 individuals produced from 22 sires and 26 dams in H. discus hannai and 297 individuals produced from 5 sires and 6 dams in H. discus discus, which evaluated by the Genetics and Breeding Research Center, National Fisheries Research & Development Institute(NFRDI). Genetic parameters were estimated for these abalone subspecies raised in Bukjeju branch, NFRDI, from May 20, 2004 to May 16, 2005, respectively. The heritability estimates obtained from restricted maximum likelihood(REML) were higher than expected, ranging from 0.40 to 0.43 for growth traits shell length, shell width and body weight in H. discus hannai and from 0.26 to 0.51 in H. discus discus, respectively. The heritabilities for shell shape and condition factor were lower than others of growth traits such as ranging from 0.09 to 0.19 in H. discus hannai and from 0.10 to 0.23 in H. discus discus, respectively. Genetic and phenotypic were > 0.93 between shell parameters and weight in two abalone species, respectively, indicating that breeding for weight gains could be successfully achieved by selecting for shell length.

• The Korean Journal of Malacology
• /
• v.23 no.2
• /
• pp.217-225
• /
• 2007

This study was conducted to estimate the general genetic parameters, heritabilities, and genetic and phenotypic correlations on growth-related traits by studying multiple trait animal model in two Korean abalone species, Haliotis discus hannai and H. discus discus. The data was collected from the records of 3,795 individuals produced from 54 sires and 74 dams in Haliotis discus hannai and 399 individuals produced from 7 sires and 7 dams in Haliotis discus discus. The data was evaluated by the Genetics and Breeding Research Center, National Fisheries Research & Development Institute (NFRDI). Genetic parameters were estimated for two abalone species raised in Bukjeju branch, NFRDI, from May 20 to November 1, 2004. The heritability estimates for growth traits of shell length, shell width and body weight obtained from restricted maximum likelihood (REML) were ranging from 0.73 to 0.78 in Haliotis discus hannai, and from 0.87 to 0.89 in H. discus discus. The heritabilities for shell shape and condition factor were ranging from 0.17 to 0.20 in Haliotis discus hannai, and from 0.01 to 0.45 in H. discus discus. Genetic and phenotypic correlations were over than 0.96 between shell parameters and weight in both of abalone subspecies, indicating that breeding for weight gains could successfully be achieved by selecting for shell length.

• Journal of Marine Life Science
• /
• v.2 no.2
• /
• pp.83-89
• /
• 2017

In abalones, interspecific hybridization has been suggested as a possible means to increase production and desired traits for the industry. In Korea, Haliotis gigantea is considered a species with a larger size and higher temperature tolerance than H. discus hannai. However, H. discus hannai is considered the most valuable and popular fishery resource due to its better acceptance and higher market prices. Thus, viable interspecific hybrids have been produced by artificial inseminating H. gigantea eggs with H. discus hannai sperm. However, the reciprocal hybrid cross was not successful. In this study, the hybridity and the growth and thermal tolerance performance of the interspecific hybrids were examined. A combination of various assays revealed maximum growth occurrence at 21℃ and the higher growth rate in the hybrids than that of H. discus hannai parent. In addition, the growth and survival at high-temperature (28℃) of the hybrids was equivalent to that of the highly tolerant H. gigantea parent, suggesting new possibilities to overcome the mass mortality in H. discus hannai during high temperature periods of summer season in Korea. Furthermore, the induced interspecific hybrid status was confirmed by the presence of species-specific bands for each parental species of the random amplified polymorphic DNA (RAPD) profiles using universal rice primer (URP), which could be used as speciesspecific markers to distinguish the hybrids and their parental species.