• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.51 no.3
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• pp.448-453
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• 2015

This study was performed to estimate biomass and to provide management plan through population ecological characteristics, including survival rate, instantaneous coefficient of natural and fishing mortalities, and age at first capture of Flathead grey mullet, Mugil cephalus, in the coastal waters of Yeosu. Survival rate (S) of the flathead grey mullet was 3.671. The instantaneous coefficients of natural mortality (M) and fishing mortality (F) was estimated to be 0.325/year, 0.962/year for flathead grey mullet. Also fist capure age of flathead grey mullet was 3.61year. The current biomass of the flathead grey mullet in the study area was estimated to be 19.6 M/T and $F_{0.1}$ and $F_{40%}$ were estimated 0.340/year, 0.225/year. For the stock assessment result, flathead grey mullet was not overfished but overfishing.

• Journal of Aquaculture
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• v.14 no.1
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• pp.29-33
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• 2001

Total length and body weight of grey mullet were 6.4cm and 2.1g, respectively at the beginning of the experiment. After 60 days of rearing, body weight of the mullet(363%) was significantly higher in freshwater group than that (187%) in seawater group. However, the condition factor showed no significant differences between seawater (9.0%) and freshwater (8.8%) groups. Survival of the mullet was 98.3% and 64.3% in seawater and freshwater groups, respectively.

• Journal of Aquaculture
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• v.12 no.4
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• pp.283-292
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• 1999

Physiological responses (cortisol, glucose, GPT, GOT, hematocrit, sodium, chloride, potassium, total protein and osmolality), growth and survival rates of grey mullet and Nile tilapia were tested by the gradual salinity changes for 70 days. Three different sizes of grey mullet, small (MS, $13.3\pm1.8cm$), middle(MM, $28.9\pm3.6cm$) and large (ML, $36.0\pm2.0cm$), and three different sizes of tilapia, small (TS,$16.5\pm1.7cm$), middle (TM, $20.6\pm1.8cm$) and large (TL, $27.2\pm2.7cm$)were used. Salinity of reareing water was increased $\5textperthousand$ in every 5 days until it reached at $0\textperthousand$. The cortisol concentrations in all size groups of grey mullet were increased at both full strength seawater (SW) and fresh water (FW) at the end. The cortisol concentrations of TM and TL groups were higher in SW than FW (0 and 70 days). The GOT values of grey mullet were lower than those of Nile tilapia. The sodium concentrations of grey mullet in SW were ranged 160~184 mEq/$\ell$, while those of Nile tilapia were the highest in the SW. No mortality was observed in MM and ML groups but survival rate of MS group was 76$\textperthousand$. Overall survival rate of Nile tilapia was lower than grey mullet. Survival rate of TS, TM and TL groups were $79\textperthousand$, $29\textperthousand$ and $55\textperthousand$, respectively.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.3
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• pp.310-316
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• 1999

Physiological responses (cortisol, glucose, GPT, GOT, total protein, hematocrit, sodium, chloride, potassium, total calcium and osmolality), growth and survival rates of grey mullet (Mugil cephalus) and Nile tilapia (Oreochromis niloticus) by the manipulation of salinity were studied. Salinity was increased directly from freshwater to $33\%_{\circ}$ and remained for 15 days. Then, salinity was decreased directly from seawater to freshwater and remained for other 15 days. All tilapias were dead at the third day, but $96.5\%$ of grey mullet were survived at the 30th day. The grey mullet showed no significant differences for cortisol and glucose concentrations in the seawater and freshwater. However, those of the Nile tilapia were increased in seawater. The grey mullet showed no significant differences for sodium, chloride and potassium concentrations during experimental period. However, those of the Nile tilapia were significantly increased when exposed to seawater. The osmolality of grey mullet ranged between 293.5 mOsm/kg and 335.0 mOsm/kg for the whole experimental period.

• Journal of Marine Life Science
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• v.4 no.2
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• pp.96-105
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• 2019

The mugilidae fishes are common euryhaline species that live in coastal marine waters to freshwater areas. The taxonomy and nomenclature of the mugilidae fishes still remain unresolved because of their morphological similarities. Among the mugilidae fishes, most commonly consumed in Korea, are grey mullet (Mugil cephalus) and red lip mullet (Chelon haematocheilus). It is generally called 'mullet' without distinguishing between two mullets. Therefore, the aim of this study is to examine the scientific names and common names of mullet species used in Korea from the domestic journals and Korean old documents. The scientific name of grey mullet is M. cephalus, but that of redlip mullet is C. haematocheilus. But the genus of redlip mullet is still mixed with Chelon, Mugil, and Liza. The standard name of two mullet is not distinguished in the Korean dictionary, but they were clearly distinguished in the Japanese, English, and Chinese dictionaries. In the ancient Korean references, the mullet was called 'Chieo' or 'Sueo'. In most of the old literature, the distinction between grey mullet and redlip mullet is not clear. However, in Jasaneobo, it was written separately from grey mullet and redlip mullet, and attaching "ga" was different from now. The Korean standard name of redlip mullet is 'gasungeo', however, the fishermen in Jeollado and Gyoungsangdo call it 'chamsungeo'. Considering the negative perception of 'ga' character, it is proposed to change 'cham(眞)' instead of 'ga(假)' to improve economic value of red lip mullet.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.47 no.3
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• pp.203-213
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• 2011

The age and growth of flathead grey mullet, Mugil cephalus, were studied using samples collected from the coastal water of Yeosu from September 2009 to August 2010. Spawning season estimated from the gonadosometic index (GSI) was from November to January. A method for increasing the readability of the otolith was described and criteria for the interpretation of otolith was provided. The annual ring was formed in September once a year. Annual ring in otolith for flathead grey mullet is validated for fish aged 1-8 using the marginal increment analysis. Using the sectioned otolith, between reader precision was 84%. Also, Within-reader agreement for sectioned otolith age readings was higher (reader 1=84%, reader 2=87%). The relationship between fork length and total weight was TW=$0.022FL^{2.818}$. The estimated von Bertalanffy growth parameters for the flathead grey mullet were $L_{\infty}$=67.97cm K=0.164/year and $t_o$=-0.81year.

• Journal of Aquaculture
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• v.12 no.1
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• pp.57-62
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• 1999

Experiments were performed to study the activity and fertility of grey mullet (Mugil cephalus) sperm after the courses of cold storage and cryopreservation. The head of spermatozoon showing spherical shape was sized $1.26{\pm}0.08 \{mu}textrm{m}$ in diameter and its nucleus contained numerous granular chromatins. Flagellum of tail showed typical 9＋2 structure. Preservation of grey mullet sperm was the most effective when it was stored with serum of the same species at $0^{\circ}C$ and sperm activity index was similar in egg-tris, 0.1 M, 0.3 M and 0.5 M glucose. When grey mullet sperm were cryopreserved in MFRS as diluent with 10% dimethyl sulfoxide was effective compared with other diluents. Some of post-thawed spermatozoa showed the enlarged head and ruptured plasma membrane compared with unfrozen spermatozoa.

• Journal of fish pathology
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• v.23 no.3
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• pp.343-355
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• 2010

This study was conducted to investigate the dietary effects of lactic acid bacteria (LAB) supplementation on growth, hematological and immune responses of grey mullet, Mugil cephalus. Three replicate groups of grey mullet (body length, $62.8{\pm}1.04\;mm$ ; body weight, $3.2{\pm}0.13\;mg$) were fed the experimental diets with 0 (control), 1, 2.5 and 5,0 % of LAB for 3 months. Total body length growth rate was increased in 2.5 % supplementation group compared to control (P<0.05). No differences were observed in hematological parameters (hematocrit, hemoglobin, RBCs) and serum chemistry (calcium, magnesium, total protein, glucose, GOT and GPT). The antioxidant activity of grey mullet fed the 5.0 % LAB diets was significantly higher than that of other groups (P<0.05). Both intracellular superoxide anion production and lysozyme activity of kidney were higher in the 2.5 % LAB diet than in the control (P<0.05).

• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.1
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• pp.51-56
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• 2001

Changes of gill tissue and body composition of grey mullet (Mugil cephalus) and Nile tilapia (Oreochromis niloticus) by the manipulation of salinity were observed in a recirculating rearing system. Salinity was increased from $0\%_{\circ}$ to $33\%_{\circ}$for 1 day and remained far 15days, thereafter salinity was decreased from $33\%_{\circ}$ to $0\%_{\circ{$ for 1 day and remained for other 15 days. Any morphological differences of gill lamella in grey mullet were not observed in seawater and freshwater. However, on day 2 in exposure to seawater, Nile tilapia showed the edema and bloodclot in gill lamella. In the case of grey mullet, mitochondria and tubular system of chloride cell were more densely packed according to the salinity increase. The whole body of grey mullet showed no significant differences in moisture content during experimental period. However, moisture content in whole body of the Nile tilapia was signincantly decreased when exposed to seawater. Protein content in whole body of grey mullet showed no significant difference between beginning and day 15 of the experiment.

• Journal of fish pathology
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• v.36 no.2
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• pp.403-408
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• 2023

Mullet is an important marine aquaculture fish species in Korea, with a total of 7,237 tons produced as of 2022, making it the 5th most produced marine aquaculture fish species. In this study, ectoparasites presumed to be isopods were discovered in the fins of farmed flathead grey mullet (average weight 550 g), and the characteristics of the parasites were confirmed. The length of the parasite was 5 to 18 mm, and 3 to 7 parasites were infected per fish. To analyze the characteristics of the parasites, molecular biological identification and phylogenetic analysis were performed using the cytochrome c oxidase subunit I (COI) gene, and it was confirmed to be most closely related to Nerocila japonica in the Cymothoidae family. To confirm the parasite control effect, a direct exposure drug sensitivity test was conducted on five types of aquatic drugs and fresh water, trichlorfon was confirmed to be effective.