Epinephelus Tauvina Research Articles

Risk assessment of toxic residues among some freshwater and marine water fish species.

Egypt has several beaches, as well as the Nile River and a few lakes; therefore, it could compensate for the lack of protein in red meat with fish. Fish, however, may become a source of heavy metal exposure in humans. The current study was to assess the level of five toxic metals, lead (Pb), cadmium (Cd), mercury (Hg), arsenic (As), and aluminum (Al), in six species, namely, Oreochromis niloticus (O. niloticus), Mugil cephalus (M. cephalus), Lates niloticus (L. niloticus), Plectropomus leopardus (P. leopardus), Epinephelus tauvina (E. tauvina), and Lethrinus nebulosus (L. nebulosus), collected from the El-Obour fish market in Egypt. The residual concentrations of the tested toxic metals in the examined O. niloticus, M. cephalus, L. niloticus, E. tauvina, P. leopardus, and L. nebulosus species were found to be higher than the European Commission's maximum permissible limits (MPL) for Pb and Cd by 10 and 20%, 15 and 65%, 75 and 15%, 20 and 65%, 15 and 40%, and 25 and 5%. In contrast, 30% of L. niloticus exceeded the MPL for Hg. It was shown that the average estimated daily intake (EDI) and the target hazard quotient (THQ) in fish samples are below safety levels for human consumption and hazard index (HI < 1). From the human health point of view, this study showed that there was no possible health risk to people due to the intake of any studied species under the current consumption rate in the country.

A checklist of fish and shellfishes of the Poonthura estuary, southwestern coast of India

A systematic checklist of fish and shellfishes of the Poonthura estuary, Kerala, India is provided including notes on their conservation status. This checklist includes 66 finfish and five shellfish, belonging to 17 orders, 35 families, and 60 genera. Carangiformes is the richest order (11 species, eight genera, and three families), representing 15.4% of the total fish diversity. Carangidae, is the most diverse family with nine representatives, contributing to 12.6% of the total fish diversity. Following the IUCN Red List Categories, of the total 69 species (excluding both exotic and transplanted fish species), 59 belong to the ‘Least Concern’, while one species Pampus argenteus is listed as ‘Vulnerable’, four are ‘Data Deficient’ (Megalops cyprinoides, Arius maculatus, Cynoglossus semifasciatus, and Epinephelus tauvina) and five are ‘Not Evaluated’ (Nuchequula blochii, Channa pseudomarulius, Penaeus indicus, P. monodon, and Scylla serrata). Around 94% of the recorded fish fauna have commercial value and contribute to subsistence fisheries throughout the year. Taxonomy and diversity of fish fauna of least studied or isolated estuarine ecosystems should be updated with proper documentation of their conservation status, in order to design and implement pragmatic management and conservation programs.

Assessment of Total Petroleum Hydrocarbon Contamination of the Red Sea with Endemic Fish from Jeddah (Saudi Arabia) as Bioindicator of Aquatic Environmental Pollution

The aim of this study was to determine whether endemic coral fish commonly consumed by Jeddah residents could serve as bioindicators of oil contamination. In addition, we planned to investigate the relationship between amino acid changes and hydrocarbon concentrations in fish tissue. The composition of amino acids was analyzed using high-pressure liquid chromatography with precolumn derivatization. An analytical study of the polycyclic aromatic hydrocarbons and total petroleum hydrocarbons was conducted by combining gas chromatography with gas chromatography/mass spectrometry. Multivariate statistical analysis was applied using Statgraphics software to determine the impact of the polycyclic aromatic hydrocarbons and total petroleum hydrocarbons on the amino acid profile of three species of fish. In addition, the bioconcentration factor was estimated in the studied species and was used to validate the results obtained from the multivariate analysis. Based on the results of the study, the sum of polycyclic aromatic hydrocarbons with two cycles, and with five to six cycles, is in reverse order in Plectropomus pessuliferus with respect to Epinephelus tauvina and Cephalopholis argus. The factor analysis showed high factor scores for aspartic acid, glutamic acid, tyrosine, chrysene, and total petroleum hydrocarbons, and for lipids and benzo(g,h,i)perylene, which could be explained by bioaccumulation. It was concluded that the high proportions of glutamic acid (8.32–11.10%) and aspartic acid (6.06–8.27%) in the muscles of the studied species are a sign of contamination with petroleum hydrocarbons. The incremental lifetime cancer risk values for the three endemic fish exceeded the limit value (&gt;10−5), indicating a high potential cancer risk for the Saudi population.

First record of Derogenes varicus and Dinurus scombri (Digenea: Hemiurata) from Red Sea fishes, Yemen

Two widely distributed and economically important food fish in the Red Sea were investigated. A total of 101 specimens of Epinephelus tauvina and 120 Abalistes stellatus were collected from Al-Mehwat local fish market, Hodeidah City, Yemen, between October 2009 and April 2010 and examined for their parasites. Two digenean species of the suborder Hemiurata, namely Derogenes varicus (Müller, 1784) and Dinurus scombri Yamaguti, 1934, were found in these fishes. The former parasite occurred in 15% of A. stellatus and 4% of E. tauvina and its mean intensity of infection was 4.2 and 3.5, respectively while the abundance was 15 and 4, respectively. The latter parasite occurred only in 1% of E. tauvina, with a mean intensity of 2 and an abundance of 0.02. The present study represents the first record of these two parasite species in Yemeni waters of the Red Sea. In addition, E. tauvina now represents a new host for D. scombri.

Comparative Analysis of Four Complete Mitochondrial Genomes of Epinephelidae (Perciformes).

Groupers are commercial, mainly reef-associated fishes, classified in the family Epinephelidae (Perciformes). This study first sequenced the complete mitogenomes of Cephalopholis leopardus, Cephalopholis spiloparaea, Epinephelus amblycephalus, and Epinephelus hexagonatus. The lengths of the four Epinephelidae mitogenomes ranged from 16,585 base pair (bp) to 16,872 bp with the typical gene order. All tRNA genes had a typical cloverleaf structure, except the tRNA-Ser (AGY) gene which was lacking the entire dihydrouridine arm. The ratio of nonsynonymous substitution (Ka) and synonymous substitution (Ks) indicated that four groupers were suffering a purifying selection. Phylogenetic relationships were reconstructed by Bayesian inference (BI) and maximum likelihood (ML) methods based on all mitogenomic data of 41 groupers and 2 outgroups. The identical topologies result with high support values showed that Cephalopholis and Epinephelus are not monophyletic genera. Anyperodon and Cromileptes clustered to Epinephelus. Aethaloperca rogaa and Cephalopholis argus assembled a clad. Cephalopholis leopardus, C. spiloparaea, and Cephalopholis miniata are also in a clade. Epinephelus hexagonatus is close to Epinephelus tauvina and Epinephelus merra, and E. amblycephalus is a sister group with Epinephelus stictus. More mitogenomic data from Epinephelidae species are essential to understand its taxonomic status with the family Serranidae.

DNA Barcoding of Commercial Three High Value Red Sea Fishes from the Egyptian Market

Fish play an essential role in food security and are regarded as one of Egypt's primary food resources and, therefore, significantly im-pact the national economy. The three main sources of fish production in Egypt: marine (Red and Mediterranean seas), lakes and the River Nile, due to the elevated incidence of species substitution at the global level, precise identification of seafood species on the mar-kets considered a solution for food safety con-trol institutions and human consumer protec-tion. Mislabeling occurs when one species is substituted for another. Different species of red sea marine fish were collected from the Egyp-tian market. According to the Arabic name in the fish market, Samples searched for English and Latin family names in (www.fishdata-base.org). Commercial samples were success-fully extracted and confirmed with 1.5% aga-rose gel electrophoresis. The result showed that the mtDNA gene cytochrome c oxidase subunit I (COI) amplification was successful for all samples with high concentration, it was purified and sequenced for both directions and blasted using the NCBI database. Resulting in the identification of three commercially essen-tial and expensive fish samples, Baghbaghan (parrotfish), Hamour (Greasy Grouper) and kahaya (Spiny squirrelfish). One of them cor-rectly identified according to the market name, while the other two are recorded mistakenly under another name.

Identifikasi Dan Prevalensi Ektoparasit Ikan Kerapu Lumpur (Epinephelus tauvina) Pada Keramba Jaring Apung Di Kuala Langsa

Greasy grouper (Epinephelus tauvina) is one type of marine fish that has economic value and can be developed into a promising cultivation commodity. The purpose of this research is to find Types of parasites and prevalence rates of ectoparasite in Greasy grouper (Epinephelus tauvina) on floating net cages in Kuala Langsa. The research method was conducted using a survey method. Sample taken by purposive sampling, amounting to 20 Greasy grouper (Epinephelus tauvina) with a size of 20-25cm and were observed at Laboratory Faculty of Agriculture, Samudra University. Fish body organs were observed including all parts of the fins, mucus, gills, then identification using microscopic and macroscopic methods. The results obtained were ectoparasites infecting Greasy grouper (Epinephelus tauvina) only one species from the genus Dactylogyrus which was found mostly in floating net cages cultivation in Kuala Langsa. These ectoparasite were found in the gill lamella Greasy grouper (Epinephelus tauvina), with the overall sample prevalence rate at 50% and the attack rate classified as “very frequent”.

Biodiversity and Efficiency of fish helminths parasites as a possible bioindicator of water quality in Jazan coastal area, Saudi Arabia

The present study was presented to assess a database about the helminthes parasites species infested marine fish in Jazan coastal area. Thus, the following sites were selected; Jazan Fishing site, Jazan coast near Aramco Company and the coastal area near the sewage treatment station. Emperor fish Lethrinus sp ., rabbitfish Siganus rivulatus, Greasy grouper Epinephelus tauvina, and the marinefish Carangoides orthogrammus were investigated. Water criteria; pH, dissolved oxygen and conductivity were determined for the selected sites. Four trematodes, two nematodes, one acanthocephalan species were detected. Larval stages of trematode, cestode, nematode and acanthocephalan were isolated. A high prevalence of infection was recorded for trematode and nematode parasites in Epinephelus tauvina, Lethrinus nebulosus, and Siganus rivulatus. No significant effect was shown for body weight or sex on the abundance of helminth parasites. Shannon-Wiener diversity index studies demonstrated the highest diversity of helminth parasites for the fishing areas and lowest helminth diversity infected Siganus rivulatus collected from the coastal area near sewage treatment station or Aramco Company. Regression analysis data showed high significant relationship between pH and conductivity on the abundance of trematode, nematode and Acanthocephala and between the dissolved oxygen concentration and the abundance of nematode and Acanthocephala at the three examined sites. Data were discussed to assess the efficiency of helminthes parasites as bioindicator for water quality in the Jazan marine ecosystem.

Assessment of genetic diversity and phylogenetic relationship among grouper species Epinephelus spp. from the Saudi waters of the Arabian Gulf.

Understanding of fish genetic characterization plays a vital role in the conservation and utilization of fish genetic resources of grouper species. The present study was carried out to assess the genetic diversity and phylogenetic relationships in five grouper species, Epinephelus spp. from eastern Saudi Arabian coast using two molecular marker systems, inter simple sequence repeat (ISSR) and microsatellite (SSR) markers. In total, 219 individuals grouper specimens (Epinephelus tauvina, E. coioides, E. bleekeri, E. malabaricus, and E. areolatus) were genotyped with 10 ISSR and 11 SSR selected primers. The ISSR produced 94 DNA fragments, of which 44 were polymorphic with an average of 2.13 fragment per primer. While SSR primers generated 107 alleles, all of them were polymorphic with an average 9.72 per primer. ISSR and SSR techniques demonstrated a high level of gene diversity and genetic distances illustrated by UPGMA dendrograms among the grouper species. The results proved that the SSR markers were highly informative and efficient in detecting genetic variability and relationships of the Epinephelus spp.

Budidaya Ikan Kerapu (Epinephelus tauvina Forsskal, 1775) dan Ikan Beronang (Siganus canaliculatus Park, 1797) dalam Karamba Jaring Apung dengan Sistim Polikultur

The aim of the present research was to evaluate the daily growth ratio, food conversion ratio and mortality of grouper (Epinephelus tauvina) and rabbit fish (Siganus canaliculatus) in floating net with polyculture system. This experiment was done at the coastal area of Tomini Bay in the North Sulawesi Province. The observations were done every two weeks for three months from August - November 2014. Twenty five groupers (62.41 grams in ABWo) and twenty five rabbit fish (52.2 grams in ABWo) were used for polyculture experiment, while fifty groupers (56.71 grams in ABWo) for monoculture. The results indicated that the daily individual growth of Epinephelus tauvina on polyculture was 1.29%, with food conversion ratio 6.1, while it on monoculture was 1,18%, with food conversion ratio 6.4. The daily individual growth of Siganus canaliculatus on polyculture was 0,8%, with food conversion ratio 3.8. Mortality for all species studied were 0%. The present research showed that the polyculture system was better than monoculture system. The future studies suggest that the polyculture system in the floating net may be developed and applied as a mariculture model in the North Sulawesi Province for prosperous life of fisherman. Keywords: Epinephelus tauvina, Siganus canaliculatus, polyculture system, floating net, prosperous life, fisherman.

New Record of Marine Parasitic Isopods (Family, Corallinidae) from South Andaman, Andaman Islands, India

Parasitic isopods are causing problems to the worldwide fishery resources. The studies on parasitic isopods are very scanty in Andaman Islands. So here we provided information on the distribution of two species of parasitic isopods of fishes from Junghlighat fish landing center of South Andaman. The two marine parasitic isopods species are Argathona rhinoceros (Bleeker 1857) and Argathon amacronema (Bleeker 1857). They found to infest the host marine fishes Epinephelus coioides (Hamilton 1822) and Epinephelus tauvina (Forsskal 1775) respectively. These two species were collected from the nostril cavity of the individual host fishes. The morphological characteristics of two specimens are described in detail. Prevalence of corallinids provides additional information to update the check list of isopods from Andaman and Nicobar Islands.

Hysterothylacium Persicum (Nematoda: Raphidascarididae) Parasite of Orangespotted Grouper Epinephelus coioides (Forsskål, 1775) Iraqi Marine Water Fishes

Hysterothylacium is one of the most important nematode parasites parasitizing fish, and it's the most diverse species nematodes of marine parasites, these species attach to the intestinal wall via their mouth lips adaptation. In the present study, seven out of 56 fish specimens (12.5 %) were found to be infected by the adult worms of Greasy grouper fishes Orangespotted grouper Epinephelus coioides (Forsskal, 1775)from locations of marine coastal water, Arabian Gulf, Iraq. A new recorded of Hysterothylacium spp. collected are morphologically described, genetically and Sccaning Electron Microscope (SEM) images for new systematic observations, on dorsal labium, sub ventral labia, posterior end of a the female and the male. Based on the study of the gene sequencer data and SEM images, it will be suggested that species are H. persicum. The study provides us some data on the taxonomy of these parasites in the Arabian Gulf. The gross examination of the fish's intestine food items and the Relationships of fish length, In this study showing that the length ranges for adult infected were 25-45 cm long, and the major food items found in the stomach were a Largest group of miscellaneous of fishes length more than 25 cm , whereas crustaceans miscellaneous parts of animal body, i.e. appendages, chela, parts of the carapace of crustaceans were found in stomachs in all the month including except some of them in stomach of length less than 20 cm , it was clear that the 25-45cm ctotal length feed mainly on fish that explain fishes are the second intermediate host of IV larval stage of nematodes. In the present reported can consider that the Epinephelus coioides as a new host for Hysterothylacium persicum and a newly recorded in Iraqi marine water . The aim of the current study is to diagnose and study new species of parasites that belong to the genus throughout the morphological studies along with the image data selected for SEM and sequence and combined with the other species of Hysterothylacium that reside in the Iraqi marine water and the relationships of fish length, food items and parasite infection.

HISTOLOGICAL AND ENZYME HISTOCHEMICAL STUDIES ON THE TRANSITIONAL

The present work was carried out using twenty mature Epinephelus tauvina (Perciforms: Serranidae) collected from Arabian Gulf coast at Dammam City. Fishes of this species are known to undergo sex change during certain stage of their life cycle. Histological and enzyme histochemical studies were performed on gonads of the collected fishes. The examination of the gonads of E. tauvina revealed the presence of three developmental phases during the sex change process. These were: Female, early transition phase and late transition phase each one may subdivide into two stages. In female phase several developmental stages of the oocytes were recognized. At the beginning of early transition phase perinucleolar mature oocytes began degeneration while late transition phase characterized by rapid proliferation of spermatogenic cells. The histochemical studies demonstrated that alkaline phosphatase enzyme gave intense reaction in granulosa cells of mature oocytes while acid phosphatase gave an intense reaction in the interstitial cells and atretic follicles but ∆5 –3β hydroxysteroid dehydrogenase enzyme gave intense reaction to special cells in capsule of gonads.

HISTOLOGICAL AND ENZYME HISTOCHEMICAL STUDIES ON THE TRANSITIONAL

The present work was carried out using twenty mature Epinephelus tauvina (Perciforms: Serranidae) collected from Arabian Gulf coast at Dammam City. Fishes of this species are known to undergo sex change during certain stage of their life cycle. Histological and enzyme histochemical studies were performed on gonads of the collected fishes. The examination of the gonads of E. tauvina revealed the presence of three developmental phases during the sex change process. These were: Female, early transition phase and late transition phase each one may subdivide into two stages. In female phase several developmental stages of the oocytes were recognized. At the beginning of early transition phase perinucleolar mature oocytes began degeneration while late transition phase characterized by rapid proliferation of spermatogenic cells. The histochemical studies demonstrated that alkaline phosphatase enzyme gave intense reaction in granulosa cells of mature oocytes while acid phosphatase gave an intense reaction in the interstitial cells and atretic follicles but ∆5 –3β hydroxysteroid dehydrogenase enzyme gave intense reaction to special cells in capsule of gonads.

Monitoring metal levels in water and multiple biomarkers in the grouper ( Epinephelus tauvina) to assess environmental stressors on the Arabian Gulf coast of Saudi Arabia.

In this field study, the levels of heavy metals (Pb, Fe, Co, Cu, and Zn) in water and a suite of biochemical and histological biomarkers in the grouper ( Epinephelus tauvina) were assessed at four sites in the Arabian Gulf. Samples were taken from a relatively non-urban reference site, called Salwa (S1), and three effluent-dominated sites, namely Al-aziziyah in southern Dammam city (S2), the Al-Jubail coast (S3), and Manifa (S4). Toxic metals, namely Pb and Co (at all sites) and Fe (at S3), were elevated in water samples relative to the internationally permissible limits. In fish, induced levels of heat shock protein 70 (HSP70) in the liver at S3 and S4 were higher than those of the reference fish at S1. Additionally, the level of the lipid peroxidation (LPO) product (malondialdehyde (MDA)) was significantly increased in gills (at S3) and liver (at S2 and S3). There was an inhibition of catalase activities in the gills of fish from S2 to S4 and significantly higher activity levels of superoxide dismutase in the gills of fish from S4. Histopathological features such as aneurysms in gill vessels, deformed gill lamellae, increases in liver melano-macrophage centers, and hepatocellular necrosis were most abundant at sites where significant pollution problems exist (i.e. S2-S4). The results reveal that the eastern coast of Saudi Arabia, in the Arabian Gulf, is still contaminated, as indicated by elevated HSP70, LPO content and numbers of histological lesions, and that monitoring of contaminants and their effects should be continued in this region.

Environmental oil pollution: a possible cause for the incidence of ankylosis, kyphosis, lordosis and scoliosis in five fish species collected from the vicinity of Jubail City, Saudi Arabia, Arabian Gulf

Spinal deformities such as scoliosis (lateral curvature), lordosis (ventral curvature), kyphosis (dorsal curvature) and ankylosis (fusion of vertebrae) have been described in many species both cultured and from the wild population. Specimens of Epinephelus tauvina, Siganus canaliculatus, Argyrops spinifer, Scomberomorus guttatus and Lethrinus nebulosus were used in this study. Four out of five deformed specimens showed abnormalities in the caudal region of the vertebral column. The specimen of E. tauvina showed the most acute deformity among the cases studied. All cases were not fatal as they occurred in adult individuals. The paper discusses the possible causes for such deformities as well as the suitability of this kind of study for environmental monitoring.

DAYA HAMBAT INFUSA RIMPANG KUNYIT (Curcuma longa Linn) TERHADAP PERTUMBUHAN Escherichia coli dan Vibrio sp. pada IKAN KERAPU LUMPUR (Epinephelus tauvina) di PASAR KEDONGANAN KABUPATEN BADUNG, BALI

ABSTRACTFish is perishable food because it contains high enough protein and water, therefore to easy damaged by microorganism. Then the control of mircoorganism should be done to maintaining the quality of fish to stay awake.Turmeric is one of the herbs that has compound content curcumin and fenolik being able to control the growth of contaminants microorganism. The objective of this research is to find out the power of immersion of mudfish grouper (Epinephelus tauvina) by infusa turmeric rhizome (Curcuma longaLinn) through sampled from Kedonganan Market, Bali. The treatment given to mudfish grouper was turmeric rhizome infusion withconcentration of 0%, 5%, 10%, 15% and 20% tested in vitro and in vivo on the growth of E. coli and Vibrio sp. The resourcesinhibited turmeric infusa rhizome is determined by counting the population of bacteria test after treatment by the method of dilution sampling (Plating Method). The results showed that turmeric rhizome infusion was able significantly (P&lt;0,05) inhibitionto the growth of E. coli and Vibrio sp. both in vitro and in vivo. The control (0%) in vitro population E. coli and Vibrio sp. each of 5,23x102 CFU/g and 4,98x102 CFU/g higher than with the treatment of concentration 5%, 10%, 15% and 20%. Population E. coli and Vibrio sp. in testing by in vivo (concentration 0%) each is obtained 4,17x102 CFU/g dan 4,20x102 CFU/g in statistic is different (P&lt;0,05) with the concentration 10%, 15% and 20%. Keywords: Epinephelus tauvina, Curcuma longa Linn, E. coli, Vibrio sp.

Levels of Organotin Compounds in Selected Fish Species from the Arabian Gulf.

In the present work, data on the levels of hazardous Organotin compounds in eight commercially important fish species, caught from Arabian Gulf, has been reported. Highest levels of tributyltin (TBT) (98.5ng/g dry weight) were detected in Epinephelus Tauvina whereas minimum (43.7ng/g) were found in Acanthoparagus Bifasciatus. Highest levels of triphenyltin (TPT) were detected in Lethrinus Miniatus (107.5ng/g) whereas lowest were encountered in Acanthoparagus Bifasciatus (64.9ng/g). Highest value of total butyltin compounds (∑BT) were found in emperors (Lethrinus Miniatus) (228.4ng/g) whereas minimum was found in Acanthoparagus Bifasciatus (126.4ng/g). Similarly highest value of total phenyltin compounds (∑PT) was encountered in Epinephelus Tauvina (281.9ng/g) followed closely by Acanthoparagus Bifasciatus (281.7ng/g). In addition, the estimated daily intake (EDI) of the local population from consumption of these fish was also evaluated. Highest EDI was found to be 10.8ng/kg bw/day for epinephelus microdan. The data are also compared internationally.

The Parasites &lt;i&gt;Monascus&lt;/i&gt; sp. (Fellodistomidae) and &lt;i&gt;Helicometrina nimia&lt;/i&gt; (Linton, 1910) (Opecoelidae) Digenea of &lt;i&gt;Pampus argenteus&lt;/i&gt; and Greasy Grouper &lt;i&gt;Epinephelus tauvina&lt;/i&gt; (Forsskl, 1775) (Teleostei: Serranidae) Fishes, Arabian Gulf, New Host and New Geographical Records

On the new investigation of some Trematode fauna of Arabian Gulf fishes, Monascus sp. a digenea parasite of pampus argenteus and Helicometrina nimia of greasy grouper, Epinephelus tauvina are register. Fish specimens were collected during the year 2016. A description of the studied specimens, besides comments concerning its taxonomic status, the morphological characters and measurements of the present material of Monascus sp. The Monascus sp. parasite are described on the present study compared with some measurements of Nine nominal species have been reported in the genus Monascus up to 1993 and showing that similarity with M. filiformis and differ in the size of parasite. The results indicated that the parasites are considered as having new hosts viz, p. argenteus and as new records in the Iraqi marine fishes. In the present study, a new host and a new host locality are presented for the two species. The taxonomic status of members of Helicometrina has been questionable, the validity of diagnostic features, especially in regard to the number of testes. In the present study, specimens presented a permanent and steady number of testes (n=9) and therefore its use as a diagnostic character and is very similar with Linton (1910). Epinephelus tauvina is considered a new host for Helicometrina nimia , and Northwest Arabian Gulf a new locality for the species.

TRAF6 is a critical factor in fish immune response to virus infection

Tumor necrosis factor receptor-associated factor 6 (TRAF6) is one of the key adaptor molecule in Toll-like receptor signal transduction that triggers downstream cascades involved in innate immunity. In our previous study, the molecular characteristics of EtTRAF6 (TRAF6 from Epinephelus tauvina), the tissue distributions, expression patterns after challenging with bacterial and viral pathogens were investigated. Here we identified EtTRAF6 as an important regulator of virus-triggered signaling pathway. Overexpression of EtTRAF6-ORF and truncated forms of EtTRAF6, including EtTRAF6-C (delete the MATH domain), EtTRAF6-N (delete the RING domain) and EtTRAF6-MATH, inhibited IFN-β activity strongly in grouper spleen (GS) cells. Overexpression of EtTRAF6 repressed virus-induced production of type I IFNs. When EtTRAF6 cotransfected with EcIRF3 or EcIRF7, EtTRAF6 inhibited IRF-induced activation of IFN-β. Over-expressed EtTRAF6 inhibited the transcription of SGIV genes significantly in GS cells. Although TRAF6 has a role in apoptosis regulation, it is not known if EtTRAF6 has any role in apoptosis regulation. Strikingly, when over-expressed in fathead minnow (FHM) cells, EtTRAF6 protected them from cell death induced by SGIV. Therefore, these results suggest that TRAF6 may play a critical role in their response to SGIV infection, through regulation of a cell death pathway that is common to fish and humans.