• 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).

• Journal of fish pathology
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• v.16 no.1
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• pp.31-38
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• 2003

The mortality of wild mullet, Mugil cephalus was detected in Kwang- Yang bay on February, 2002. The mullet were infected with Myxobolus sp., the cysts of Myxobolus sp. were found in the mesentery, liver, gill and pharyngeal pocket. The histological findings suggested a systemic infection by the Myxobolus sp.. The spores were measured 10-12 (10.9)${\mu}m$ in length, 9-10 (9.4) ${\mu}m$ in width, 6.4-7.2 (6.8) ${\mu}m$ in thickness, with polar capsules of 4-5.2 (4.4) ${\mu}m$ in length and 2.5-3.3 (2.9) ${\mu}m$ in width.

• Parasites, Hosts and Diseases
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• v.46 no.2
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• pp.77-82
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• 2008

Fishborne zoonotic metacercariae have not been reported from brackish water and marine fish from Vietnam waters although these parasites are common in the country's freshwater fish. Both wild-caught and cultured grouper (Epinephelus coioides and Epinephelus bleekeri), and mullet (Mugil cephalus) from brackish and marine waters located in Khanh Hoa province in central coastal Vietnam were examined, and found positive for zoonotic trematode metacercariae. From grouper, Heterophyopsis continua and Procerovum varium were recovered. The prevalence of H. continua ranged from 2.0 to 6.0% and that for P. varium ranged from 11.6 to 15.8%. Mullet were infected with Pygidiopsis summa and H. continua; both of these species are new records for Vietnam. The prevalence of P. summa in mullet was generally high, ranging from 17.6 to 75.5%, and was significantly higher than the prevalence of H. continua (2.5 to 32.4%). There were no significant differences in the prevalence of metacercariae between grouper from natural or cultured habitats, indicating that the highest risk of infection occurs in the wild-caught state prior to their placement in culture. Further, there was no difference in metacercarial prevalence between the 2 species of grouper. Infected wild-caught seed were only observed from January to October. Monthly variation in prevalence suggests seasonal variation in mullet infections occurs in this region with the highest transmission taking place from October to December. Basic investigations on the ecology and epidemiology of these intestinal flukes need to be carried out to determine their significance as a public health problem and the aspects of their biology that may be vulnerable to control interventions.

• Fisheries and Aquatic Sciences
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• v.25 no.11
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• pp.559-571
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• 2022

Galectins, a family of ß-galactoside-binding lectins, have emerged as soluble mediators in infected cells and pattern recognition receptors (PRRs) responsible for evoking and regulating innate immunity. The present study aimed to evaluate the role of galectin-1 in the host immune response of redlip mullet (Liza haematocheilia). We established a cDNA database for redlip mullet, and the cDNA sequence of galectin-1 (LhGal-1) was characterized. In silico analysis was performed, and the spatial and temporal expression patterns in gills and blood in response to lipopolysaccharide polyinosinic:polycytidylic acid, and Lactococcus garvieae were estimated via quantitative real-time PCR. Functional assays were conducted using recombinant protein to investigate carbohydrate binding, bacterial binding, and bacterial agglutination activity. LhGal-1 was composed of 135 amino acids. Conserved motifs (H-NPR, -N- and -W-E-R) within the carbohydrate recognition domain were found in LhGal-1. The tissue distribution revealed that the healthy stomach expressed high levels of LhGal-1. The temporal monitoring of LhGal-1 mRNA expression in the gill and blood showed its significant upregulation in response to immune challenges with different stimulants. rLhGal-1 exhibited binding activity in response to carbohydrates and bacteria. Moreover, the agglutination of rLhGal-1 against Escherichia coli was observed. Collectively, our findings suggest that LhGal-1 may function as a PRR in redlip mullet. Furthermore, LhGal-1 can be considered a significant gene to play a protective role in redlip mullet immune system.

• 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.

• Fisheries and Aquatic Sciences
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• v.19 no.4
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• pp.19.1-19.7
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• 2016

A laboratory experiment was conducted to determine hexavalent chromium ($Cr^{6+}$) accumulation in the mullet and investigate $Cr^{6+}$ toxicity using a panel of biomarkers including metallothioneins (MTs), glutathione (GSH), glutathione S-transferase (GST), and superoxide dismutases (SODs) for 4 weeks. $Cr^{6+}$ bioaccumulation in all tissues, except muscle, was consistently time- and dose-dependent. The accumulation of $Cr^{6+}$ for 4-week exposures was in the following order: $kidney{\approx}liver$ > $intestine{\approx}gill$ > spleen > muscle. Compared with the control, $Cr^{6+}$ bioaccumulation was increased in ${\geq}200{\mu}g\;L^{-1}$ groups (P < 0.05). An independent relation was observed between accumulation factors (AFs) and exposure concentration. But AFs increased with exposure time. In the liver and gill, GST and SOD differed from the control at a high $Cr^{6+}$ concentration at 2 and 4 weeks (P < 0.05). This study indicated that the gills were as sensitive as the liver to $Cr^{6+}$ toxicity. However, the latter appeared to influence largely on the organism's adaptive response to $Cr^{6+}$, since $Cr^{6+}$ may elevate GSH and MT levels by enhancing the hepatic uptake of metal in the mullet.

• Fisheries and Aquatic Sciences
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• v.3 no.2
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• pp.78-82
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• 2000

The influence of daily water temperature changes on chemiluminescent (CL) response of phagocytes, plasma glucose level and mortality in cultured gray mullet (Mugil cephalus) was investigated. Among three experimental temperature groups, the fish in group I and group II were maintained constantly at $27^{\circ}C$ and $29^{\circ}C$, respectively, and those in group III were suffered daily elevation of water temperature from $27^{\circ}C$ to $29^{\circ}C$ for 5 hours, then restored again to $27^{\circ}C$. After 1 week of maintaining at each experimental tank, the fish in group III showed significantly lower CL peak value (p < 0.01) and higher plasma glucose levels (p < 0.05) than those in group I and group II. The cumulative mortality of group III was $86.9\%$ within 3 days after being subjected to acute handling stress. On the other hand, the cumulative mortalities of group I and group II were $12.5\%$ and $19.2\%$, respectively. In conclusion, gray mullet farms, especially, in the vicinity of thermoelectric power plants should avoid stressing the fish during periods of high water temperature.

• Parasites, Hosts and Diseases
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• v.44 no.1 s.137
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• pp.7-13
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• 2006

Heterophyid metacercarial infections in brackish water fishes, i.e., perch, shad, mullet, redlip mullet, and goby, of Jinju-man (Bay), Kyongsangnam-do, Korea, were investigated using a digestion technique. Among 45 perch (Lateolabrax japonicus), the metacercariae of Heterophyopsis continua were found in $55.6\%$ (18.5 metacercariae per fish), Stictodora spp. in $28.9\%$ (3.6), and Metagonimus takahashii in $6.7\%$ (17.0). The metacercariae of H. continua were detected in 23 $(65.7\%)$ of 35 shad (Konosirus punctatus). Among 15 mullet (Mugil cephalus), the metacercariae of Pygidiopsis summa were found in $100\%$ (105.9 metacercariae per fish), Heterophyes nocens in $40.0\%$ (8.5), H. continua in $13.3\%$, and Stictodora spp. in $6.7\%$. Among 12 redlip mullet (Chelon haematocheilus), the metacercariae of P. summa were detected in $91.7\%$ (1,299 metacercariae per fish), H. nocens in $16.7\%$, and Stictodora spp. in $16.7\%$. Among 35 gobies (Acanthogobius flavimanus), the metacercariae of Stictodora spp. were found in $82.9\%$ (44.5 metacercariae per fish), and H. continua in $25.7\%$ (2.8). The adult flukes recovered from a cat experimentally infected with metacercariae from perches were compatible with M. takarashii. The results confirm that the estuarine fish in Jinju-man (Bay) are heavily infected with heterophyid metacercariae. Furthermore, it was found for the first time that the perch acts as a second intermediate host for M. takahashii.

• Animal cells and systems
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• v.15 no.3
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• pp.189-196
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• 2011

We investigated the in vitro effects of nonylphenol (NP) and 3,3',4,4',5-pentachlorobiphenyl (PCB126) on steroidogenesis in redlip mullet, Chelon haematocheilus, oocytes. In experiment 1, we investigated the effects of NP and PCB126 on steroid production from exogenous steroid precursors. Vitellogenic oocytes (0.75 mm in diameter) were incubated with 10 and 100 ng/ml NP or PCB126 with $[^3H]17{\alpha}$-hydroxyprogesterone as a precursor. The major metabolites produced were androstenedione, testosterone (T), estrone, and estradiol-$17{\beta}$ ($E_2$). Both NP and PCB126 increased T production and decreased $E_2$ production, except for 100 ng/ml PCB126. In experiment 2, oocytes (0.65-0.75 mm in diameter) were exposed to NP and PCB126 at different concentrations (0.01, 0.1, 1, 10, and 100 ng/mL). After the incubation, T and $E_2$ production was measured by radioimmunoassay. NP inhibited $E_2$ production at concentrations of 0.01 and 0.1 ng/ml in 0.75-mm-diameter oocytes. NP at 1 and 100 ng/mL stimulated T production, but had no observable effect on $E_2$ production. PCB126 treatment did not affect $E_2$ production at any of the concentrations tested. NP alone at 0.1 ng/mL resulted in a significant decrease in $E_2$ production in 0.65-mm-diameter oocytes. PCB126 did not show any significant effects on either T or $E_2$ production at all concentrations tested. These results suggest that NP acts like an antiestrogen at lower concentrations (0.01-0.1 ng/ml) in vitellogenic oocytes of redlip mullet.

• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.5
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• pp.503-508
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• 1991

The salted and dried mullet(Mugil Japonicus) roe had about 42% of protein and 41% of lipid content as major compoments. Therefore the lipid oxidation and the deterioration of protein occurred during drying and storage periods. In order to keep the good quality of the dried roe, acid, peroxide, thiobarbituric acid value and the contitutional amino acid were studied in the different drying air velocities at the conditions of 60% R.H. and $20^{\circ}C$ of drying air temperature. The optimum air velocity showed 2m/sec, which was excellently superior to the lipid and protein quality than those of other air velocities on the dried mullet roe. The drying period shortened from 20 days in the conventional processing method to 7 days in the modified processing method that had 2m/sec of drying air velocity. The drying rate curve had only a falling-rate drying period and not to have a constant-rate drying period.