• Proceedings of the Zoological Society Korea Conference
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• 1999.10b
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• pp.245.1-245
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• 1999

No Abstract, See Full Text

• Proceedings of the Zoological Society Korea Conference
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• 1997.10b
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• pp.91.1-91
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• 1997

No Abstract, See Full Text

• Fisheries and Aquatic Sciences
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• v.25 no.1
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• pp.40-48
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• 2022

Seahorses, which have been cultivated since the 2000s, are economically very important. Gas bubble disease (GBD) is a significant concern in the cultivation of seahorses; therefore, this study aimed to determine the cause of GBD-induced death in two species of Syngnathidae (Syngnathus schlegeli and Hippocampus haema). Rod-shaped bacteria were observed histopathologically and identified as Vibrio splendidus by conventional and real-time PCR analyses. The lethality of V. splendidus varies depending on the host's immune status, and the disease can be prevented through water quality management or improvement of the breeding environment. In this study, the GBD lesions (gas bubbles) were observed at 12℃, 8.0 mg/L of dissolved oxygen, 30 ppt of salinity, and pH 7.7. In addition, rod-shaped bacteria, infiltration of inflammatory cells, and extensive serous exudate were confirmed in the lesions where gas bubbles were found. PCR analysis was able to detect V. splendidus, possibly a secondary infection of the immunocompromised syngnathid fish. Understanding the risk of immunity control and the correlation between these lesions and causal agents will be of great help to the aquaculture industry and the ornamental fish market.

• Korean Journal of Environmental Biology
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• v.38 no.3
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• pp.476-480
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• 2020

A marine red algal species was collected from Uljin, located on the eastern coast of Korea, during a survey of marine algal flora. This alga shares the generic features of Plocamium, and is characterized by linear, flat and thin thalli with narrow axes, branches developing in alternating pairs from margins of the axes, two to four times alternately pinnately branching, linear or occasionally adaxially curved lowermost branchlets and distinctly and compactly clustered stichidia. In a phylogenetic tree based on rbcL sequences, the Korean alga nests in the same clade as P. serrulatum. The genetic distance between both sequences within the clade was calculated as 0.0-0.2%. Based on the morphological and molecular data, this Korean species is identified as P. serrulatum described originally from Taiwan. This is the first record of P. serrulatum in Korean marine algal flora.

• Korean Journal of Environmental Biology
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• v.38 no.3
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• pp.481-485
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• 2020

A marine red algal species was collected from Honghyeon-ri, Namhae located on the southern coast of Korea during a survey of marine algal flora. This alga shares the generic features of Chondrus, and is characterized by short and thin, canaliculated and crisped fronds as C. retortus. Tetrasporangia are developed from shallow medullary cells on both sides of branches. In a phylogenetic tree based on rbcL sequences, the Korean alga nests in the same clade as C. retortus originally described from Japan. The genetic distance between both sequences within the clade was calculated as 0.0-0.1%. Based on the morphological and molecular data, the alga is identified as Chondrus retortus. This is the first record of C. retortus in Korean marine algal flora.

• Korean Journal of Environmental Biology
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• v.38 no.4
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• pp.611-615
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• 2020

A marine red algal species was collected from Pyengdae-ri, Gujwa in Jeju, Korea during a survey of marine algal flora. This alga shares the generic features of Callophyllis(Gigartinales, Kallymeniaceae), and is characterized by erect and membranous thalli, branches dichotomously or trichotomoulsy divided, margin somewhat undulate or entire and tetrasporangia scattered irregularly in the cortex. In a phylogenetic tree based on rbc L sequences, the Korean alga nests in the same clade as C. mageshimensis originally described from Japan. The genetic distance between both sequences within the clade was 0.0-0.1%. Based on the morphological and molecular data, the alga was identified as Callophyllis mageshimensis. This is the first record of C. mageshimensis in Korean marine algal flora.

• Parasites, Hosts and Diseases
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• v.61 no.3
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• pp.332-337
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• 2023

Infestations of parasites, particularly those caused by copepods and monogeneans, are a major hindrance to aquaculture and have a big negative economic impact. Sebastes schlegelii, a farmed Korean rockfish, is particularly prone to copepods and monogeneans. This study comprehended how parasitic copepods and rockfish from a farm in Tongyeong-si, Gyeongsangnam-do, Korea, are related to the monogenean trematode Microcotyle sebastis. Our research revealed that monogeneans predominated, with a rate of 98.4% and an average infection intensity of 7 per infected fish. With an average infection intensity of 4 per sick fish, the infection rate for parasitic copepods was equally considerable, coming in at 91.7%. The high co-infection rate of both parasite families, at 90.8%, is noteworthy. Furthermore, Lepeophtheirus elegans and Peniculus truncatus, 2 parasitic copepod species, were discovered to have M. sebastis eggs attached to their bodies. This demonstrates a connection between parasitic copepod infestations in farmed Korean rockfish and the monogenean trematode M. sebastis. These discoveries highlight the necessity for creating more potent parasite control methods for the aquaculture sector and shed light on the intricate relationships between various parasite species.

• Korean Journal of Ichthyology
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• v.34 no.4
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• pp.253-261
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• 2022

After exposing Olive flounder and Korean rockfish to the concentration ranges of control (0 mg/L), 100 mg/L, 250 mg/L, 500 mg/L, and 1,000 mg/L, to investigate the physiological properties of suspended load on fish AST/GOT, ALT/GPT, ALP and cortisol were analyzed. As a result of the analysis, the AST/GOT, ALT/GPT, ALP and cortisol values were higher in the suspended load concentration section than in the control group. After artificial infection with S. parauberis for Olive flounder and V. harveyi for Korean rockfish exposed to suspended load, the survival rate was higher in the control group than in the suspended load concentration section. These results are related to the previously study results of suspended load that adversely affect fish, suggesting that suspended load affects the health of fish.

• Journal of fish pathology
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• v.29 no.1
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• pp.1-5
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• 2016

Isopods are parasitic crustaceans that pose serious threat to fisheries. Several studies have tried to explore the host-pathogen relationship between marine fishes and isopods. The present study aims to understanding the secondary infections in marine fishes pertaining to isopods. To assess the secondary infection in infected fishes, parasite infested and healthy tissues of fishes were collected. The samples were subjected to standard microbiological procedure to identify the presence of pathogenic bacteria and fungi. Our results showed the branchial region had the higher microbial load of non-sporulating cenocytic fungi in infected fishes. Moreover, fungal strains isolated from the parasitic lesion confirmed that the parasitation and body lesion facilitates the entry of several pathogenic microbes at the damaged host tissue. More over the immune regulation of fish fights back by producing minute cysts, trying to encapsulate the growing fungus. But this may eventually lead to systemic infestation and death of the fish.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.57 no.1
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• pp.53-59
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• 2024

The reproductive biology of the Washington clam Saxidomus purpuratus, from Yeosu, Korea was investigated based on 699 individuals collected from January to December 2022. The sex ratio of this species was not significantly different from a 1:1 (male:female) sex ratio (P>0.05). Monthly changes in gonadosomatic index were analyzed to estimate the spawning season. The reproductive cycle of this species can be divided into the following stages: active (Jan.-Mar.), ripe (Mar.-Nov.), spent (Apr.-Dec.), and degenerative (Jun.-Dec.) stages. The spawning period ranged from March to December with the main periods being from April to June and from September to November. The shell length at 50% female group maturity (SL₅₀) was estimated to be 60.2 mm.