• Korean Journal of Ichthyology
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• v.5 no.2
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• pp.208-216
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• 1993

The territorial behavior of the naked goby, Gobiosoma bosci, was observed in 80-liter aquaria. Social behavior was observed for an extended time in daily observation periods. Individuals of G. bosci, regardless of size and sex, exhibited agonistic behavior. The aggresive behaviors of approaching, threatening, attacking, and fighting were recorded as agonistic behavior. All individuals are capable of changing their color and camouflaging themselves by matching the color of bottom. Especially, the resident and the intruder are of the same size, the fighting duration was prolonged and the variability of coloration was at its peak.

• Korean Journal of Ichthyology
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• v.25 no.1
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• pp.38-41
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• 2013

A deep-dwelling goby, Obliquogobius yamadai, was described as the first record from Korea based on three specimens (30.3~47.0 mm SL) collected from the southern sea off Jeju Island. The species is characterized by having I, 9 second dorsal fin rays, scaled lateral side of nape, smaller head with large eye, and asymmetrical caudal fin dorsoventrally as well as about nine yellowish bars on body side. A new Korean name, "Gip-eun-ba-da-no-ran-ddi-mang-dug", is proposed for the species.

• Development and Reproduction
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• v.23 no.2
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• pp.111-117
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• 2019

This study focused on the association of prostaglandins and a progestin, $17{\alpha}$, $20{\beta}P$-dihydroxy-4-pregnen-3-one ($17{\alpha}20{\beta}P$) during the ovulation process in longchin goby, Chasmichthys dolichognathus. We performed several in vitro experiments using $850-920{\mu}m$ diameter oocytes which were at the migratory nucleus stage. With the $890-920{\mu}m$ diameter oocytes, no significant difference in ovulation was observed in any of the prostaglandins (PGE1, PGE2, and $PGF2{\alpha}$) treated groups although PGE2 and $PGF2{\alpha}$ at concentrations of 50 ng/mL increased ovulation slightly compared with controls; however, $17{\alpha}20{\beta}P$ production was stimulated with PGE1 alone at low concentrations (5 ng/mL). In $850{\mu}m$ diameter oocytes, $PGF2{\alpha}$ at concentrations of 50 and 500 ng/mL resulted in a significant increase in ovulation. $17{\alpha}20{\beta}P$ (50 ng/mL) alone had no observable effect on ovulation, but in the combined of $PGF2{\alpha}$ 50 or 500 ng/mL it caused the greatest effect on ovulation. The sensitivity of oocytes to the induction of ovulation varies between 850 and $890-920{\mu}m$, it appeared to vary depending on the migration status of nucleus. These results suggest that $PGF2{\alpha}$ (or combined of $17{\alpha}20{\beta}P$) was more potent in inducing ovulation of the longchin goby.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.2 no.1
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• pp.47-62
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• 1969

A goby, Synechogobius hasta (Temminck et Schlegel) was studied to investigate the food consumed and the biological change of the food organisms, and the fish were sampled from the closed tributary and the lower Part of the Naktong River, near Pusan, during the period from November of 1967 to December of 1968. The fish were sampled from four stations (Fig. 1), the total number of fish being 1,295 and they were grouped and analysed monthly. The content of the alimentary canal was analysed in three categories according to modified Nilsson's method (Dahl 1962) with a slight alteration: 1) The number of each item of stomach contents was counted and the percentage of each item in proportion to the total number of food organisms is indicated by the letter 'N' representing numerical percentage in Table 2. 2) The percentage of fish which contained any items of food organisms in proportion to the total number of fish caught in a given season is indicated by the letter 'O' representing frequency of occurrence. 3) Dominant groups of food items were selected and the percentage of the number of each dominant item in proportion to the number of the food organisms belonging to the dominant groups is indicated by the letter 'D' representing dominance. All food organisms were classified in 50 food item categories and then they were grouped in 13 main groups (Fig. 2-1), and they were further divided into 1) obligatory bottom animals, 2) organic drifts and 3) actively swimming forms; according to the conditions of the animal communities within the habitat. Since the majority of its food was composed of the obligatory bottom animals ($94.6\%$), the fish appeard to be a typical bottom feeder. And the dominant food organisms of the fish is generally determined by the local composition of the benthic fauna within the fish habitat. And their seasonal rhythm occurs among the food organisms in the stomach by the biological interaction. Locality variation in the population of the same food organism occurs due to the difference of food organisms in the habitat of the fish at Seonam and Garak, and at Seongsan and Hadan the condition of the niche for the fish in the both regions seems to be the same since the composition and the seasonal variation of the organisms were the same. The results may be summarized as follows: 1) The goby mainly feed on the animals of bottom fauna, and the food organisms are deter-mined by the food compositions within the habitat. 2) Seasonal variation of the stomach content shows the seasonal rhythm due to the biological variation of the population and their interaction. 3) The goby shows no preference on specific food, and the food is composed of a variety of animals. 4) Major food items of the goby are Polychaeta, Palaemon modestus, Isopoda, Gammaridea, Insecta (nymphs and larvae), Ilyoplax deschampsi, and Paratye compressa. 5) Logitudinal succession oil the population of the food organisms is apparently recognized within the community of Seongsan, Garak and Seonam. 6) The goby begins to descend toward the estuary and sea around April when the water temperature reaches $20^{\circ}C$, and they begin to return to river waters in September.

• Development and Reproduction
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• v.20 no.3
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• pp.207-217
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• 2016

In this study, we investigated the characteristics of CCK-producing cells and mucus-secreting goblet cells with respect to stomach fish and stomachless fish of the Gobiidae in order to provide a basis for understanding the digestive physiology. Hairychin goby (Sagamia geneionema), which is stomachless fish, the numbers of mucus-secreting goblet cells is highest in the posterior intestine portion (P<0.05), while CCK-producing cells are scattered throughout the intestine. Gluttonous goby (Chasmichthys gulosus), which is stomach fish, mucus-secreting goblet cells are most abundant in the mid intestine portion (P<0.05), whereas CCK-producing cells are observed only in the anterior and mid intestine portion. Trident goby (Tridentiger obscurus) which is stomach fish, mucus-secreting goblet cells were most abundant in the mid intestine portion (P<0.05). CCK-producing cells are found in the anterior and mid intestine portion. Giurine goby, Rhinogobius giurinus which is also stomach fish, the largest number of mucus-secreting goblet cells showed in anterior intestine portion except for esophagus (P<0.05). CCK-producing cells are present only in the anterior and mid intestine portion. In S. geneionema, digestive action occurs in the posterior intestine portion to protect and functions to activate digestion. In contrast, in C. gulosus, T. obscurus and R. giurinus, their digestive action occurs in the anterior and mid intestine portion to protect and functions to activate digestion. Further studies of the modes of food ingestion by these fish, the contents of their digestive tracts, and the staining characteristics of the goblet cells need to be carried out.

• Development and Reproduction
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• v.12 no.1
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• pp.107-112
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• 2008

To investigate the $C_{21}$-steroids produced from maturating oocytes in the longchin goby, Chasmichthys dolichognathus, the oocytes ($0.74{\sim}0.97\;mm$) were incubated with radiolabeled $17{\alpha}$-hydroxyprogesterone ($^3H-17{\alpha}OHP$) for 24 hours. The resulting metabolites were analyzed by thin layer chromatography and identified by gas chromatography-mass spectrometry. Two $C_{21}$-steroids, $17{\alpha}$-hydroxy, $20{\alpha}$-dihydroprogesterone ($17{\alpha}20{\alpha}P$) and $17{\alpha}$-hydroxy, $20{\beta}$-dihydroprogesterone ($17{\alpha}20{\beta}P$), were converted from $^3H-17{\alpha}OHP$ in the maturing oocytes. These two main metabolites were detected at 0.80 mm diameter oocytes or greater. In addition, the effects of these metabolites on in vitro germinal vesicle breakdown (GVBD) were tested. The sensitivity of oocytes to the induction of GVBD was greater at $17{\alpha}20{\beta}P$ than $17{\alpha}20{\alpha}P$. This result showed that $17{\alpha}20{\beta}P$ is a major maturation inducing steroid (MIS) in longchin goby, suggesting $17{\alpha}20{\alpha}P$ may play a role in regulating the oocyte maturation process.

• Proceedings of the Zoological Society Korea Conference
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• 2003.08a
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• pp.133.3-133
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• 2003

No Abstract, See Full Text

• Parasites, Hosts and Diseases
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• v.43 no.4 s.136
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• pp.161-164
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• 2005

A survey was performed in order to determine the infection status of the metacercariae of heterophyid fluke in two goby species, Boleophthalmus pectinirostris and Scartelaos sp., collected from Gangjin-gun, and Shinan­gun, Sooncheon-shi, Jeollanam-do, Republic of Korea. A total of three metacercariae of Heterophyopsis continua was found in only one B. pectinirostris $(10.0\%)$ from Gangjin-gun. Heterophyes nocens metacercariae were detected in 24 B. pectinirostris $(96.0\%)$ and 14 Scartelaos sp. $(63.6\%)$ from Shinan-gun. Heterophyopsis continua metacercariae were found in 11 B. pectinirostris $(44.0\%)$ and 21 Scartelaos sp. $(95.5\%)$ from Shinan-gun. Stictodora fuscata metacercariae were detected in 18 B. pectinirostris $(72.0\%)$ from Shinan-gun. No metacercariae were detected in 20 B. pectinirostris from Sooncheon-shi. From the above results, this study is the first to prove that B. pectinirostris and Scartelaos sp. serve as the second intermediate hosts of some heterophyid flukes in Korea.

• Korean Journal of Ichthyology
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• v.19 no.1
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• pp.66-69
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• 2007

Seventeen specimens (29.1~50.7 mm SL) of the starry goby, Asterropteryx semipunctata, were collected from the southern coast of Jeju Island, Korea, and described as the first record from Korea. The species is characterized by having separated pelvic fins, five to eight short spines on posterior margin of preopercle, and numerous blue spots on head, body and unpaired fins except for first dorsal when fresh. We proposed a new Korean name, 'Cheong-byeol-mang-duk', for the species.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.52 no.2
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• pp.169-175
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• 2016

The feeding habits of yellowfin goby (Acanthogobius flavimanus) were studied based on the examination of stomach contents of 171 specimens collected from September 2013 to August 2014 in the tidal flat of Sangnae-ri, Suncheon, Korea. The size of A. flavimanus ranged from 10.6 to 18.3 cm in standard length (SL). A. flavimanus mainly consumed amphipods (especially Corophium sp.). Its diet also included shrimps, crabs, fishes and polychaetes. Ontogenetic changes in diet composition of A. flavimanus were evident. The portion of amphipods and polychaetes was inversely proprotional to the increase in fish size whereas it was directly proportional to the increase in the consumption of shrimps and crabs increased.