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Abstract: Golden pompano, Trachinotus blochii is a new marine fish candidate for aquaculture in Malaysia. The fingerlings of the fish are not yet produced locally but imported from neighboring countries and Taiwan. In the present study we report the first molecular detection of betanodavirus from diseased golden pompano fingerlings cultured in a deep-sea cage culture facility in Langkawi, Malaysia. The virus caused the fish fingerlings to exhibit abnormal swimming behavior, dark skin coloration and loss of appetite prior to mass mortality. Histopathological examination revealed acute cell vacuolation in both brain and retina tissues of the affected fingerlings. Results of viral culture, RT-PCR and DNA sequencing further confirmed the role of betanodavirus infection in the outbreak. Although phylogenetic analysis and mean nucleotide sequence of RNA2 genome of the betanodavirus showed high similarity to RGNNV betanodavirus isolated from Taiwan, origin of infection is difficult to establish since the RGNNV is also commonly reported in the Southeast Asian region and has the widest range of host marine fish species. Nevertheless, the finding of the present study requires a review of procedures in importing fish fingerlings for sustainable growth of the marine aquaculture industry in Malaysia. [Copyright &y& Elsevier]

A low-head recirculating aquaculture system (RAS) for the production of Florida pompano, Trachinotus carolinus, from juvenile to market size was evaluated. The 32.4-m³ RAS consisted of three dual-drain, 3-m diameter culture tanks of 7.8-m³ volume each, two 0.71-m³ moving bed bioreactors filled with media (67% fill with K1 Kaldness media) for biofiltration, two degassing towers for CO2 removal and aeration, a drum filter with a 40-µm screen for solids removal, and a 1-hp low-head propeller pump for water circulation. Supplemental oxygenation was provided in each tank by ultrafine ceramic diffusers and system salinity was maintained at 7.0 g/L. Juvenile pompano (0.043 kg mean weight) were stocked into each of the three tanks at an initial density of 1.7 kg/m³ (300 fish/tank). After 306 d of culture, the mean weight of the fish harvested from each tank ranged from 0.589 to 0.655 kg with survival ranging from 57.7 to 81.7%. During the culture period, the average water use per kilogram of fish was 3.26 or 1.82 m³ per fish harvested. Energy consumption per kilogram of fish was 47.2 or 22.4 kwh per fish harvested. The mean volumetric total ammonia nitrogen (TAN) removal rate of the bioreactors was 127.6 ± 58.3 g TAN removed/m³ media-d with an average of 33.0% removal per pass. Results of this evaluation suggest that system modifications are warranted to enhance production to commercial levels (>60 kg/m³). [ABSTRACT FROM AUTHOR]

Abstract: Mass mortality of snubnose pompano Trachinotus blochii fry exhibiting dark coloration, anorexia, and abnormal swimming behavior was recently documented at the hatchery of the Aquaculture Department of the Southeast Asian Fisheries Development Center, Philippines. Samples of brain tissues were collected from affected fish and processed for RT-PCR amplification and virus isolation in cell culture. Infected E-11 cells exhibited cytopathic effect characteristic of betanodavirus. Histopathology of moribund fish showed pronounced vacuolations in the brain, spinal cord, and retina. An RT-PCR product of approximately 430bp was amplified from the culture supernatant of betanodavirus-infected E-11 cells and sequenced. Sequencing of the T4 region of the coat protein gene (RNA 2) revealed clustering of the isolated virus within the red-spotted grouper nervous necrosis virus type. The pathogenicity of the isolated betanodavirus in healthy pompano juveniles and fry was determined via intramuscular injection and immersion challenges, respectively. Higher mortality rates were obtained in challenged fish compared with the controls. An inactivated vaccine was subsequently prepared by treating the clarified betanodavirus with formalin. Pompano juveniles intraperitoneally injected with the inactivated vaccine exhibited neutralizing antibodies from days 15 (mean titer 1:240) to 125 (1:560) with the highest titer noted at day 64 (1:2240) post-vaccination. Additionally, pompano fry bath-vaccinated and consequently bath-challenged with betanodavirus at day 35 post-vaccination showed higher survival rate compared with the control, indicating the potential of the inactivated betanodavirus vaccine against VNN in pompano fry and juveniles. [ABSTRACT FROM AUTHOR]

Abstract: The apparent digestibility coefficient (ADC) of energy of various vegetable feed ingredients with relatively high levels of carbohydrate was determined for Florida pompano, Trachinotus carolinus. A practical fish meal and soybean meal based reference diet was formulated to contain 54% protein, 11% lipid, and 1% chromic oxide. Using the 70:30 replacement strategy seven test diets were produced that included corn grain, sorghum grain, whole wheat flour, wheat bran, wheat middlings, full fat rice bran, and defatted rice bran. Each of the diets were offered to juvenile pompano (111.6g mean weight) maintained in a recirculation system. After one week of conditioning to the diets, fecal samples were obtained by manually stripping the fish. Chromium content and gross energy of the diets and fecal samples was then determined and digestibility coefficients calculated. The ADC of energy of the evaluated feedstuffs showed a wide variation, ranging from 8.2% for wheat middlings, to 55.4% for whole wheat flour. Knowing the contribution of common vegetable feed ingredients to the digestible energy content of production diets is critical to achieve cost-effective formulations that may lead to a reduction in the overall feeding cost of Florida pompano production, providing useful information to improve feed formulations for this species. [ABSTRACT FROM AUTHOR]

Abstract: Red-spotted grouper nervous necrosis virus (RGNNV) causes high mortality in marine fish larvae cultured in China. To control better an outbreak of this virus, a rapid, specific and sensitive detection method based on loop-mediated isothermal amplification (LAMP) was developed. A set of four primers, two outer and two inner, was designed from RGNNV genome RNA. The LAMP reaction mix was optimized. The method was specific as no cross-reaction was observed between white spot syndrome virus, koi herpesvirus, infectious spleen and kidney necrosis virus, mud crab reovirus, and grass carp hemorrhage virus. The sensitivity of LAMP was 100-fold higher than the nested PCR in detecting the presence of RGNNV. RGNNV was detected in the brain of Trachinotus ovatus that showed typical symptoms of NNV infection, with the standardized LAMP procedure. [Copyright &y& Elsevier]

The aim of this experiment was to evaluate the efficacy of benzocaine and eugenol as anesthetics for Trachinotus marginatus juveniles. Five concentrations of benzocaine (25, 50, 75, 100, and 150ppm) and eugenol (25, 37.5, 50, 62.5, and 75ppm) were tested. The trials were conducted in glass aquariums filled with 30l seawater (salinity 30‰ and temperature 19°C). The fish (51.4±13.5g) were individually exposed to different concentrations of each anesthetic (n=5 for each concentration). They were measured and weighed under anesthesia, and then returned to another aquarium without anesthetic for recovery. The results were evaluated using Analyses of Variance (One-Way - ANOVA) followed by the test of Duncan (95% confidence level) when necessary. Anesthesia time varied from approximately 11min (25ppm) to 2min (150ppm) for benzocaine, and from 10min (25ppm) to 2min (75ppm) for eugenol. Recovery time ranged from 3min (25ppm) to 14min (150ppm) for benzocaine and from 2min (25ppm) to 8min (75ppm) for eugenol. Benzocaine and eugenol, both at 50ppm, induce quick anesthesia and recovery (3mim for anesthesia and 5mim for recovery) for juvenile Trachinotus marginatus, and therefore are considered efficient anesthetics for this species. However, it is important to emphasize that the cost of benzocaine is 1/3 lower than eugenol to anesthetize juvenile pompano. [ABSTRACT FROM AUTHOR]

Juvenile Florida pompano (6.3 ± 0.50 g) were fed 1 of 12 diets formulated with an array of crude protein (340, 380, 420, 480, or 500 g/kg diet) and crude lipid (60, 100, 120, 160, or 180 g/kg diet) levels and estimated digestible protein to digestible energy (DP/DE) of 18.9–26.8 mg/kJ. In a second trial, apparent protein and energy digestibilities were empirically determined and coefficients used to calculate actual digestibilities. Digestible energy (DE) intake was 4.2–13.0 kJ/fish/d, and digestible protein (DP) intake was 0.13–0.32 g/fish/d. Average daily gain increased as a function of both DP and energy. Growth increased with increasing DP in all diets containing 24.0 mg/kJ DP/DE or greater until a plateau at 366 g DP/kg. Nitrogen gain was also a function of both DP and DE. Increasing energy at constant protein improved protein utilization. DP to maximize growth and nitrogen gain was between 356 and 366 g/kg. DE to attain maximum growth in juvenile Florida pompano is at least 15.4 MJ/kg with a DP/DE between 23.8 and 25.1 mg/kJ. [ABSTRACT FROM AUTHOR]

We present the complete mitochondrial genome of the Trachinotus ovatus in this study. The mitochondrial genome is 16,563 bp long and consists of 13 protein-coding genes, two rRNA genes, 22 tRNA genes and a control region. The gene order and composition of T. ovatus mitochondrial genome was similar to that of most other vertebrates. The nucleotide compositions of the light strand are 29.03% of A, 28.86% of C, 26.23% of T and 15.88% of G. With the exception of ND6 and eight tRNA genes, all other mitochondrial genes are encoded on the heavy strand. Two copies of tandem repeat sequence (56 bp) was observed in the 5′ end of the control region. [ABSTRACT FROM AUTHOR]

Describes the culture performance of indigenous palometa Trachinotus goodei. Diets given to palometa; Effect of diet on absolute growth rate; Relative growth rate; Feed conversion ratio; Mean condition factors.

The golden pompano (Trachinotus blochii) is a marine fish species in tropical regions. No information about genetic variation and population structure of wild populations is available. A first set of 12 polymorphic microsatellites isolated from this species were characterized. The number of alleles ranged from 5 to 14 with an average of 8.0 alleles per locus. All 12 markers conformed to HWE and were in linkage equilibrium. These 12 microsatellite markers supply the first set of co-dominant DNA markers for studying population genetics of the species T. blochii. [ABSTRACT FROM AUTHOR]

Abstract: The present study was conducted to estimate the acute toxicity of unionized ammonia–nitrogen (NH3–N) and nitrite–nitrogen (NO2–N) to juvenile pompano Trachinotus marginatus (0.86±0.21 g) at different salinity levels: 5, 10 (equivalent to its isosmotic point), and 30‰. Fish were acclimated to the different salinities for 10 days and fed ad libitum daily. Groups of five fishes were exposed to five concentrations of NH3–N and NO2–N for 96 h plus control groups for each salinity, where no toxicant was added. Test concentrations ranged from 0.28 to 3.53 mg NH3–N/L and 24.8 to 191.1 mg NO2–N/L with three replicates per treatment. Tests were run using a standard semi-static system with 100% daily renewal of water and toxicants. The results were based on mortality data registered in different concentrations tested, using the software Trimmed Spearman Karber method. The median lethal concentrations (LC50) after 96 h of exposure to NH3–N were 0.66 (0.53–0.81), 1.87 (1.65–2.12) and 1.06 (0.94–1.20) mg NH3–N/L for 5, 10, and 30‰. The 96 h LC50 to NO2–N were 39.94 (36.39–43.84), 116.68 (112.52–121.00) and 37.55 (20.91–67.44) mg NO2–N/L for 5, 10, and 30‰. Acute toxicity of NH3–N and NO2–N to pompano was affected by salinity. Results of the present study show that pompano reared at an isosmotic environment are less sensitive to NH3–N and NO2–N. Tolerance to NH3–N is compromised at reduced salinities, while toxicity of NO2–N is similar at 5 and 30‰. [Copyright &y& Elsevier]

The complete mitochondrial genome ofTrachinotus ovatuswas determined by the polymerase chain reaction (PCR). The mitogenome is 16,564 bp long and has the typical vertebrate mitochondrial gene arrangement, including 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes and one control region. The overall base composition of mitogenome is estimated to be 29.0% for A, 28.9% for C, 26.2% for T, 15.9% for G, respectively, with a high A + T content (55.2%). With the exception ofND6and eight tRNA genes, all other mitochondrial genes are encoded on the heavy strand. The control region contains a dinucleotide repeat motif, (AT)5. This mitogenome sequence would play an important role in population genetics and the molecular taxonomy ofT. ovatus. [ABSTRACT FROM AUTHOR]

The complete mitochondrial genome ofTrachinotus blochiiwas determined using the polymerase chain reaction. The complete mitochondrial DNA sequence is 16,558 bp in length. It consists of 13 protein-coding genes, 22 transfer RNA genes, two rRNA genes and two non-coding regions. Overall base composition of its mitochondrial genome is estimated to be 29.21% for A, 15.74% for G, 26.49% for T, 28.56% for C, respectively, with a high A + T content (55.70%). The control region contains three conserved sequence blocks, a termination-associated sequence and a TATA box. The complete mitochondrial genome sequence ofT. blochiican provide a basic data for the studies on population structure, molecular systematic, stock evaluation and conservation genetics. It is also helpful to develop the rational management strategies forT. blochiiresource. [ABSTRACT FROM AUTHOR]

To understand the effect of woody forages on golden pompano (Trachinotus ovatus) intestinal bacteria diversity and exploit new aquafeed ingredients, the diets of Moringa oleifera Lam (MOL), Broussonetia papyrifera (BP), Neolamarckia cadamba (NC) and Folium mori (FM) formulated with 70% of reference (Ref) diet and 30% of the four woody plants leaves were fed to golden pompano with initial body weight of 34.4 ± 0.5 g for 56 days, respectively. Bacteria diversity of golden pompano intestine and tank water (W) samples were analyzed using high-throughput illumina sequencing and the result indicated that the dominate phyla of golden pompano intestine were Proteobacteria, Bacteroidetes, Firmicutes and Fusobacteria. Proteobacteria in BP was significantly higher than those in NC (P < 0.05). Firmicutes in NC were significantly higher than those in BP and FM (P < 0.05). At genera level, Lactobacillus in NC was significantly higher than those in BP, MOL and FM groups (P < 0.05). The PCoA and heat map analyses showed that the intestinal bacteria community of golden pompano fed with woody forages and Ref diet presented higher similarity and the bacteria community of golden pompano intestine were clearly distinguished from those of W. Phylogenetic investigation of communities by reconstruction of unobserved states showed that the intestinal bacteria dominant metabolism pathways of golden pompano fed with woody forages and Ref diet were biosynthesis of amino acids and carbon metabolism. Overall, the present study first successfully characterized the intestinal bacteria diversity of golden pompano. [ABSTRACT FROM AUTHOR]

Two trials were conducted to determine the effects of diet supplemented with organic selenium (OS, Selplex, Alltech, Kentucky USA) on survival, physiological, and immunological parameters of snub-nosed dart (Trachinotus blochii Lacepide, 1801) when challenged with Nocardia sp. bacteria or when exposed to toxic levels of environmental copper. The fish were fed two different diets containing 0% (D1,control diet) and 0.03% OS (D2) for 12 weeks before challenge. Cumulative mortality, phagocytic activity, and respiratory burst of head kidney leucocytes, and physiological parameters including moisture content and lipid accumulation in the liver, moisture content, and crude protein in the flesh were recorded. Results showed that the cumulative mortality of fish fed Se supplemented diet was lower than that of the fish fed the control diet when challenged with Nocardia sp. Survival rate was 100% in both treatment groups when exposed to copper only. Phagocytic activity and respiratory burst were higher in fish fed D2 (Se supplemented) compared to the D1 group when challenged with Nocardia sp. Phagocytic activity was higher in fish fed Se supplemented diet compared to the control group when exposed to environmental copper. No significant differences in the protein content, total lipid, and moisture in liver and flesh were recorded between the diet groups. Results indicated that supplementation of 0.3 g/Kg of OS (Sel-Plex) in the diet of snub-nosed dart is recommended to enhance fish survival and immunity when challenged with bacteria Nocardia sp. and environmental Cu toxicity exposure. [ABSTRACT FROM AUTHOR]

The present study was conducted to investigate the effects of dietary marine red yeast Rhodotorula mucilaginosa supplementation on the growth performance, non-specific immune responses, and resistance to the pathogen Vibrio harveyi in Golden Pompano Trachinotus ovatus. A basal diet was supplemented with R. mucilaginosa at 0‰ (control), 1‰, 2‰, 3‰, 4‰, and 5‰ for 8 weeks. After the 8-week feeding trial, weight gain (WG) and specific growth rate (SGR) were significantly affected by the R. mucilaginosa levels, with the highest WG and SGR occurring at the 1‰ R. mucilaginosa level (P<0.05). Compared to the control, the 4 and 5‰ R. mucilaginosa groups had significantly increased lysozyme (LYZ) and alkaline phosphatase (AKP) activity, but a decrease in nitric oxide synthase (NOS) was noted (P<0.05). Compared to the control, the 2, 3 and 4‰ R. mucilaginosa groups had significantly increased hepatic superoxide dismutase (SOD) activity (P<0.05), while hepatic malondialdehyde (MDA) content decreased significantly (P<0.05). After challenge with V. harveyi, the group supplemented with 1‰ R. mucilaginosa had 100% survival rate. In addition, compared to the control group prior to challenge, the serum C3 level significantly increased in the group supplemented with 2‰ R. Mucilaginosa (P < 0.05). Compared to the control 12 h and 48h after challenge, serum C4 levels in the 4‰ R. Mucilaginosa group increased significantly (P < 0.05). Our results suggested that ingestion of a basal diet supplemented with 1-3‰ R. mucilaginosa in T. ovatus could enhance resistance against the pathogen Vibrio harveyi. [ABSTRACT FROM AUTHOR]