Lateolabrax Japonicus Research Articles

Genome-wide identification of Fgfr genes and function analysis of Fgfr4 in myoblasts differentiation of Lateolabrax maculatus

Fibroblast growth factor receptors (Fgfrs) are involved in cell proliferation, differentiation, and migration via complex signaling pathways in different tissues. Our previous studies showed that fibroblast growth factor receptor 4 (fgfr4) was detected in the most significant quantitative trait loci (QTL) for growth traits. However, studies focusing on the function of fgfr4 on the growth of bony fish are still limited. In this study, we identified seven fgfr genes in spotted sea bass (Lateolabrax maculatus) genome, namely fgfr1a, fgfr1b, fgfr2, fgfr3, fgfr4, fgfr5a, and fgfr5b. Phylogenetic analysis, syntenic analysis and gene structure analysis were conducted to further support the accuracy of our annotation and classification results. Additionally, fgfr4 showed the highest expression levels among fgfrs during the proliferation and differentiation stages of spotted sea bass myoblasts. To further study the function of fgfr4 in myogenesis, dual-fluorescence in situ hybridization (ISH) assay was conducted, and the results showed co-localization of fgfr4 with marker gene of skeletal muscle satellite cells. By treating differentiating myoblasts cultured in vitro with BLU-554, the mRNA expressions of myogenin (myog) and the numbers of myotubes formed by myoblasts increased significantly compared to negative control group. These results indicated that Fgfr4 inhibits the differentiation of myoblasts in spotted sea bass. Our findings contributed to filling a research gap on fgfr4 in bony fish myogenesis and the theoretical understanding of growth trait regulation of spotted sea bass.

Impacts of cage aquaculture of Asian seabass (Lates calcarifer) on the water quality parameters of Kalnagini Creek at Kakdwip in West Bengal

Impacts of cage aquaculture of Asian seabass (Lates calcarifer) on the water quality parameters of Kalnagini Creek at Kakdwip in West Bengal

Effects of chitosan-gentianic acid derivatives on the quality and shelf life of seabass (Lateolabrax maculatus) during refrigerated storage

Chitosan is a natural polymer material with antibacterial, biodegradable and biocompatibility. At present, the research is mainly to enhance the antibacterial and antioxidant activity of chitosan by grafting with phenolic acids to further expand its application in food. In this study, the effect of chitosan-g-gentisic acid graft copolymer (CS-g-GA) on the shelf life of refrigerated seabass (Lateolabrax maculatus) was investigated. The results of microbial analysis demonstrated that GA and CS-g-GA treatment could effectively inhibit the growth of microorganisms. In addition, physicochemical analysis showed that GA and CS-g-GA treatment could reduce the increase of pH value, thiobarbituric acid reactive substances (TBARS), total volatile base nitrogen (TVB-N) and K-value, delay water loss, maintain texture and color, and postpone the decrease of sensory score. Compared with the control sample, CS-g-GA could keep the quality of Lateolabrax japonicus and extend its shelf-life for another 9 days. In summary, CS-g-GA has good application and development prospects for the preservation of seabass.

Reparative potentials of commensal-derived cellular components in juvenile Lateolabrax maculatus fed high soybean meal diet: Insight into growth performance, immunity, antioxidant capacity and liver health

An eight-week feeding trial was designed to estimate the effects of commensal Bacillus siamensis LF4-derived whole cell wall (CW), cell wall protein (CWP), lipoteichoic acid (LTA) and peptidoglycan (PGN) supplementation in a high soybean meal (SM) diet on the growth, immunity and liver health of spotted seabass (Lateolabrax maculatus). Fish continuously fed low SM (containing 16 % SM) and high SM (containing 40 % SM) diets were served as positive (LSM) and negative (HSM) control, respectively. After feeding high SM diet for 28 days, fish were fortified with B. siamensis LF4-derived CW, CWP, LTA or PGN until 56 days. The results showed that CW, LTA, and PGN application significantly increased FBW, WGR, and SGR (P<0.05), but not affect CF, VSI, HSI, IFR, ILI, and ISI (P＞0.05) in spotted seabass (L. maculatus) fed with high SM diet. Distal intestinal protease activity reduction caused by dietary high SM inclusion was significantly repaired when spotted seabass (L. maculatus) fortified with LTA and PGN (P<0.05). CW, LTA and PGN administration effectively increased serum immunity by enhancing ACP activity and C3, C4, IgM contents and reduced IL-1β content in serum of spotted seabass (L. maculatus) fed high SM diet (P<0.05). Significantly decreased serum MDA content in groups CW, LTA and PGN and significantly increased liver GSH content in group CWP were observed as compared to those in group HSM (P<0.05). Dietary CW, LTA and PGN supplementation, rather than CWP, repaired SM-induced liver injury by improving liver morphology and significantly reducing GOT and GPT activities (P<0.05). In summary, CW, LTA and PGN derived from B. siamensis LF4 effectively repaired SM-induced growth, feed utilization, immunity suppression and liver injury in spotted seabass (L. maculatus).

Comparative Nutritional and Histological Analysis of Malabar Red Snapper (Lutjanus malabaricus) and Asian Seabass (Lates calcarifer).

This study offers a comprehensive morpho-histological analysis of the gastrointestinal tract (GIT) of the Malabar red snapper. A comparison of its GIT morphology with that of the Asian seabass reveals similarities and differences between the two species. Additionally, the moisture content, crude protein, and ash in the fillets of Malabar red snapper and Asian seabass were slightly different, with Malabar red snapper exhibiting higher levels of essential fatty acids. Furthermore, higher levels of the polyunsaturated fatty acid (PUFA)/saturated fatty acid (SFA) ratio and docosahexaenoic acid (DHA)/eicosapentaenoic acid (EPA) ratio, and a lower omega-6/omega-3 ratio, were observed in Malabar red snapper compared to Asian seabass. The Malabar red snapper's esophagus featured protective mechanisms such as simple columnar epithelial cells, mucous-secreting glands, and goblet cells that were predominantly stained for acid and neutral mucosubstances. Furthermore, its stomach, with mucus cells that were weakly stained for acid mucosubstances, exhibited distinct regions with varying glandular densities, with the pyloric region featuring few glands. The pyloric caeca of the fish were composed of five finger-like structures and few goblet cells. Several goblet cells gradually increased from the anterior to the posterior region of the intestine. These findings provide useful insights for the aquaculture sector, focusing on Malabar red snapper.

Unveiling the molecular regulatory mechanisms of immune responses in the spleen of spotted sea bass (Lateolabrax maculatus) against Nocardia seriolae infection

Spotted sea bass holds significant economic importance in China's aquaculture sector. The outbreaks of bacterial diseases, especially caused by Nocardia seriolae (N.seriolae), have occurred frequently due to intensive farming. With the high morbidity and mortality, fish nocardiosis is one of the most serious problems faced by the aquaculture industry of spotted sea bass. However, the regulatory mechanism of immune response in spotted sea bass after N.seriolae infection remain elusive. In our study, we conducted a comprehensive examination of clinical symptoms and histological structures of the spleen, revealing noticeable pathological changes in diseased fish. Subsequently, we employed transcriptome sequencing of the spleen to investigate the effect of N.seriolae on spotted sea bass at 0 h, 48 h, 96 h and 120 h at transcriptome level. A total of 3031, 3597, and 4683 differentially expressed genes (DEGs) were unveiled in 48 h vs. 0 h, 96 h vs. 0 h and 120 h vs. 0 h, respectively. Up-regulated DEGs were significantly enriched in PRRs and cytokine related pathways, while down-regulated DEGs exhibited significant enrichment in autophagy related pathways, suggesting potential roles in immune modulation. Weighted co-expression network analysis (WGCNA) identified a blue module strongly linked to the immune response against N.seriolae infection, from which 10 hub genes were identified, including ilr2, tnfrsf9, c7 and so on. Moreover, our findings highlighted the involvement of alternative splicing (AS) in the immune response and found that pathogen infection also induced the AS events in some immune-related genes. Our study could shed new light on the molecular regulatory mechanisms underlying the immune response after N. seriolae infection in spotted sea bass, providing a basic guidance for the breeding of spotted sea bass with disease resistance in the future.

Tbx21 gene and its association with resistance against viral nervous necrosis (VNN) in Asian seabass, Lates calcarifer

Tbx21 gene and its association with resistance against viral nervous necrosis (VNN) in Asian seabass, Lates calcarifer

Review of current perspectives and future outlook on bacterial disease prevention through vaccination in Asian seabass (Lates calcarifer).

Asian seabass, Lates calcarifer, is an important aquatic species in mariculture. Intensive farming of this species has faced episodes of bacterial diseases, including those due to vibriosis, scale drop, and muscle necrosis disease, big belly disease, photobacteriosis, columnaris, streptococcosis, aeromoniasis, and tenacibaculosis. Vaccination is one of the most efficient, non-antibiotic, and eco-friendly strategies for protecting fish against bacterial diseases, contributing to aquaculture expansion and ensuring food security. As of now, although numerous vaccines have undergone laboratory research, only one commercially available inactivated vaccine, suitable for both immersion and injection administration, is accessible for preventing Streptococcus iniae. Several key challenges in developing vaccines for Asian seabass must be addressed, such as the current limited understanding of immunological responses to vaccines, the costs associated with vaccine production, forms, and routes of vaccine application, and how to increase the adoption of vaccines by farmers. The future of vaccine development for the Asian seabass industry, therefore, is discussed with these key critical issues in mind. The focus is on improving our understanding of Asian seabass immunity, including maternal immunity, immunocompetence, and immune responses post-vaccination, as well as developing tools to assess vaccine effectiveness. The need for an alignment of fish vaccines with state-of-the-art vaccine technologies employed in human and terrestrial animal healthcare is also discussed. This review also discusses the necessity of providing locally-produced autogenous vaccines, especially for immersion and oral vaccines, to benefit small-scale fish farmers, and the potential benefits that might be extended through changes to current husbandry practices such as the vaccination of broodstock and earlier life stages of their off-spring.

Regulatory effects of Astragalus membranaceus polysaccharides on lipid metabolism disorders induced by a high-fat diet in spotted sea bass (Lateolabrax maculatus)

This study evaluated the regulatory effects of Astragalus membranaceus polysaccharides (AMP) on lipid metabolism disorders induced by a high-fat diet (HFD) in spotted sea bass (Lateolabrax maculatus). Compared with the normal diets (10 % lipids), diets containing 15 % lipid levels were used as the high-fat diet (HFD). Three levels of the AMP (0.06 %, 0.08 %, 0.10 %) were added in the HFD and used as experimental diets. A total of 375 spotted sea bass (average weight 3.00 ± 0.01 g) were divided into 15 tanks and deemed as 5 groups, with each tank containing 25 fish. Fish in each group were fed with different diets for 56 days. After feeding, the HFD induced lipid metabolism disorders in fish, as evidenced by elevated serum lipids, malonaldehyde levels, and more severe liver damage. The AMP alleviated the HFD-induced liver damage, as evidenced by the reduced severity of liver histological lesions and malonaldehyde levels. The low-density lipoprotein cholesterol was reduced, and the expression of FAS and PPAR-α were down and up-regulated, respectively. However, the AMP had a limited ability to affect the serum lipids and abdominal fat percentage. These results reveal the potential of the AMP used in aquaculture to regulate lipid metabolism disorders induced by the HFD.

Application of Ulva lactuca polysaccharide in the preservation of refrigerated of Lateolabrax maculatus fillets

This study aimed to explore the use of Ulva lactuca polysaccharide (ULP) as a preservative for perch (Lateolabrax maculatus) fillets stored under refrigeration at 4 °C. Fresh perch fillets were treated with ULP (7–10 kDa) and potassium sorbate, respectively, to evaluate their effectiveness in inhibiting bacterial growth and maintain freshness. A 0.5% ULP solution significantly decreased the pH value, total volatile basic nitrogen value, thiobarbituric acid value, and total bacterial count of perch fillets. ULP solution delayed the changes in whiteness and texture of fillets, as well as protein degradation. The acute toxicity experiment further evaluates the safety and reliability of ULP. Simultaneously, utilizing 16S rRNA techniques, the ULP solution inhibited microorganisms known for their strong spoilage capabilities, such as Pseudomonas, Actinetobacter, and Shewanella. Microorganisms with a weaker ability to cause corruption became the dominant bacteria, such as Acetobacter, Lactobacillus, and Faecalibacterium, thereby exerting a degree of inhibition against spoilage.

Sequential development of histopathological manifestations in response to experimental infection of Vibrio alginolyticus in Asian Seabass

Sequential development of histopathological manifestations in response to experimental infection of Vibrio alginolyticus in Asian Seabass

Immune Rejection Mediated by prf1 and gzmb Affects the Colonization of Fat Greenling (Hexagrammos otakii) Spermatogonia in Heterotransplantation.

Fish germ cell transplantation holds great potential for conserving endangered species, improving cultured fish breeds, and exploring reproductive techniques. However, low transplantation efficiency is a common issue in heterotransplantation. This study transplanted fat greenling (Hexagrammos otakii) spermatogonia into the testes of spotted sea bass (Lateolabrax maculatus) to investigate factors that might affect the colonization and fixation of heterologous transplanted germ cells. Results indicated that transplanted fat greenling spermatogonia cells were successfully detected in the early transplantation phase in spotted sea bass. Their numbers gradually decreased over time, and after 10 days post-transplantation, more than 90% of the transplanted cells underwent apoptosis. Transcriptome sequencing analysis of the testes of spotted sea bass and fat greenling spermatogonia on days 1 and 10 post-transplantation revealed that this apoptosis process involved many immune-related genes and their associated signaling pathways. Acute immune rejection marker genes prf1 and gzmb were detected in the spotted sea bass testes, while immune tolerance genes lck and zap-70 were expressed in the fat greenling spermatogonia. Additionally, differential expression of prf1 and gzmb genes was screened from spotted sea bass, with experimental evidence indicating that PRF1 and GZMB protein from spotted sea bass primarily induce apoptosis in transplanted fat greenling spermatogonia via the mitochondrial apoptosis pathway, at the protein level. This suggests that the difficulties in heterotransplantation are primarily related to acute immune rejection, with PRF1 and GZMB playing significant roles.

Effect of Biologger Attachment on the Stress and Health State of the Spotted Sea Bass Lateolabrax maculatus

The biologger is a widely used tool in biotelemetry for investigating marine fish. However, studies reported that the attachment of biologgers has a negative effect on the target organisms. We assessed the health status of spotted sea bass with attached biologgers by analyzing changes in their serum biochemistry and biomarker gene expression at varying biologger/fish body weight ratios. Especially, the assessment of the health status using biomarker genes offers the rapid evaluation of the condition of an individual. The genes bax, hsp70-2, and Cx32.7, associated with apoptosis, stress, and immunity, were selected as biomarker genes to assess the fish stress levels and overall health. The experimental groups included a control group without the biologger (C) and biologger-equipped groups, each carrying a biologger whose weight was 2.0–3.0% (W2), 5.0–6.0% (W5), and 10.0–12.0% (W10) of the fish body weight. Blood samples were collected on days 0, 1, 7, 14, and 21 post-attachment. The expression of bax, hsp70-2, and Cx32.7 was analyzed in the liver and muscle on day 21. The W10 group showed significantly higher levels of superoxide dismutase on day 1 and of glutamic oxaloacetic transaminase and glutamic pyruvic transaminase on day 7 than the other groups. On day 21 post-attachment, regardless of the biologger/fish body weight ratio, the liver and muscle tissues from groups W2, W5, and W10 showed significantly higher expression of bax, hsp70-2, and Cx32.7 than those from group C, respectively. However, there was no significant change in blood parameters depending on the weight of the attached biologger on day 21 post-attachment. These results indicate that the spotted sea bass gradually adapted to the attached biologgers of weights up to 10–12% of their body weight under our experimental conditions, providing clues to determine the timing of biologger release for biotelemetry studies.

LTA and PGN from Bacillus siamensis can alleviate soybean meal-induced enteritis and microbiota dysbiosis in Lateolabrax maculatus

An eight-week feeding trial was designed to assess which component of commensal Bacillus siamensis LF4 can mitigate SBM-induced enteritis and microbiota dysbiosis in spotted seabass (Lateolabrax maculatus) based on TLRs-MAPKs/NF-кB signaling pathways. Fish continuously fed low SBM (containing 16 % SBM) and high SBM (containing 40 % SBM) diets were used as positive (FM group) and negative (SBM group) control, respectively. After feeding high SBM diet for 28 days, fish were supplemented with B. siamensis LF4-derived whole cell wall (CW), cell wall protein (CWP), lipoteichoic acid (LTA) or peptidoglycan (PGN) until 56 days. The results showed that a high inclusion of SBM in the diet caused enteritis, characterized with significantly (P < 0.05) decreased muscular thickness, villus height, villus width, atrophied and loosely arranged microvillus. Moreover, high SBM inclusion induced an up-regulation of pro-inflammatory cytokines and a down-regulation of occludin, E-cadherin, anti-inflammatory cytokines, apoptosis related genes and antimicrobial peptides. However, dietary supplementation with CW, LTA, and PGN of B. siamensis LF4 could effectively alleviate enteritis caused by a high level of dietary SBM. Additionally, CWP and PGN administration increased beneficial Cetobacterium and decreased pathogenic Plesiomonas and Brevinema, while dietary LTA decreased Plesiomonas and Brevinema, suggesting that CWP, LTA and PGN positively modulated intestinal microbiota in spotted seabass. Furthermore, CW, LTA, and PGN application significantly stimulated TLR2, TLR5 and MyD88 expressions, and inhibited the downstream p38 and NF-κB signaling. Taken together, these results suggest that LTA and PGN from B. siamensis LF4 could alleviate soybean meal-induced enteritis and microbiota dysbiosis in L. maculatus, and p38 MAPK/NF-κB pathways might be involved in those processes.

Evaluation of quercetin in alleviating the negative effects of high soybean meal diet on spotted sea bass Lateolabrax maculatus

The aim of this study was to investigate the effects of quercetin (QUE) on alleviating the negative effects of high soybean meal diet for spotted sea bass Lateolabrax maculatus. A healthy control group fed a 44% fishmeal diet was used, while the induction control group replaced 50% fishmeal with soybean meal. Subsequently, QUE was added at concentrations of 0.25, 0.50, 0.75, and 1.00 g/kg in the experimental groups. A total of 540 tailed spotted sea bass were randomly divided into 6 groups and fed the corresponding diet for 56 days. The results showed that 40% soybean meal significantly decreased the growth performance and immunity, increased the intestinal mucosal permeability, and caused damage to the intestinal tissue morphology; moreover, there were alterations observed in the composition of the intestinal microbiota, accompanied by detectable levels of saponins in the metabolites. However, the addition of QUE did not yield significant changes in growth performance; instead, it notably reduced the permeability of the intestinal mucosa, improved the body's immunity and the structural integrity of the intestinal tissue, increased the proportion of Proteobacteria, and enhanced the richness and diversity of intestinal microorganisms to a certain extent. In addition, QUE up-regulate the metabolism of amino acids and their derivatives and energy-related metabolites such as uridine and guanosine; furthermore, it appears to regulate transporters through the ABC transporters pathway to promote the absorption and utilization of QUE by enterocytes.

Genomic predictions for daily gain and fillet weight using correlated size and body area measurements in Asian seabass (Lates calarifer, Bloch 1790)

Genomic prediction models have proven efficient for increasing genetic gains of growth and fillet traits in aquaculture. However, measurement of these traits is expensive, time-consuming, or cannot be performed on live animals. This study investigated the potential of using correlated body traits as an alternative basis for supporting genomic prediction of average daily gain (ADG) and fillet weight (FW) in Asian seabass. A total of 954 fish were genotyped for 20,430 single nucleotide polymorphisms (SNPs). Phenotypic data at 390 days, including body weight, fillet weight, 16 size and four body-part-area measurements were used. Heritability estimates were high for ADG (0.47) and FW (0.44), low to moderate (0.12–0.39) for body sizes and body areas. Genetic correlations among pairs of traits were all high and positive (0.65–0.99). Five prediction models (1, 2, 3, 4 and 5) were evaluated using the GBLUP method and were compared using five-fold cross validation. Results indicated that model 4, which fitted the secondary traits derived from correlated body sizes and body areas as the phenotypes, was the best model, showing prediction accuracy of 0.47 with small prediction bias (0.95). The results demonstrated the advantage of using correlated traits for practical genomic prediction in Asian seabass, particularly for growth and fillet traits that are difficult to measure.

Genetic diversity, heritability, and estimated breeding values for growth of domesticated Asian seabass Latescalcarifer from Thailand

To establish a new breeding program, genetic diversity of five domesticated populations and two commercial stocks of Asian seabass (Lates calcarifer) were examined. Moderate levels of genetic diversity based on microsatellite polymorphism were found. The number of alleles per locus (NA) was 3.429–11.571. Observed (Ho) and expected (He) heterozygosities were 0.416–0.772 and 0.423–0.805. FST and genetic heterogeneity analysis revealed significant genetic differences of most pairwise comparisons (P < 0.001). Genetic distance between populations was 0.000–0.703. Phylogenetic analysis divided examined populations to two genetic stocks; A: DOF-Chachoengsao 2, DOF-Songkhla, and DOF-Trang and B: Commercial Farm 1 (Phuket) and Commercial Farm 2 (Chachengsao), DOF-Chachoengsao 1 and DOF-Krabi. The base population (G0, 51 families) was established from crosses between these founder populations. Heritability and estimated breeding values (EBVs) for growth in G0 families were evaluated at 519 day post hatch (dph, mean body weight = 616.64 ± 266.80 g, N = 1655). The heritability (h2) for growth of L. calcarifer in this study was 0.386 ± 0.020. The additive genetic coefficient of variation was 28% indicating high potential of genetic improvement for growth in this population. The distribution of EBVs showed high variation both between and within families. Fish exhibiting high EBVs (SATREPS-DOF-G0-hEBVs) clustered with a phylogenetic clade A while the SATREPS-DOF-G0-lEBVs group was phylogenetically allocated to clade B. Genetic selection with +1SD criteria is expected to achieve genetic gain of 28.5% per generation. The information on genetic diversity and EBVs estimates allows efficient implementation of our ongoing breeding program of L. calcarifer.

Combined hurdle effects of pulsed electric field and ultraviolet-C irradiation on microbial load reduction and composition of hemeproteins from Asian seabass gills

The combined effects of two non-thermal technologies, namely pulsed electric field (PEF) and ultraviolet-C (UV–C) irradiation, on microbial load reduction and composition of crude hemeprotein extract (CHPE) from Asian seabass gills were investigated. PEF at two intensities (15 kV and 17.5 kV) for different times (0, 1, 2.5, 5 and 10 min) was employed to treat CHPE solution. Subsequently freeze-dried PEF treated powders were exposed to UV-C for varying durations (0, 15 and 30 min). Microbial community in gill and selected CHPE powders was also determined using next generation sequencing (NGS). PEF treatment effectively reduced the initial microbial load (8.0 log10 CFU/g) when high PEF intensity (17.5 kV) for longer treatment time (5 min) was employed, leading to microbial load reduction to 5.5 log10 CFU/g. However, prolonged PEF treatment adversely affected CHPE properties, as witnessed by the decreased heme iron content and alterations in protein patterns. Subsequent UV-C irradiation of freeze-dried PEF-treated CHPE powder for 15 min demonstrated a synergistic effect on further reduction of microbial counts to 3.0 log10 CFU/g. NGS analysis showed the dominance of Flavobacteriaceae families in the microbial community composition in gill, untreated CHPE powder and PEF-UV-C treated CHPE powder. Nevertheless, no Vibrio parahaemolyticus and other Vibrio spp. were detected in all samples. The study revealed the potential of combined non-thermal hurdle technologies, under appropriate conditions, in ensuring microbiological safety and maintaining quality of CHPE. CHPE powder could therefore be used for fortification in food products as an iron supplement to alleviate iron-deficient anemia.

Effects of Dietary Supplementation of Bile Acids on Growth, Glucose Metabolism, and Intestinal Health of Spotted Seabass (Lateolabrax maculatus).

An 8-week feeding trial was performed to investigate the effects of dietary bile acids on growth, glucose metabolism, and intestinal health in spotted seabass (Lateolabrax maculatus) reared at high temperatures (33 °C). The fish (20.09 ± 1.12 g) were fed diets supplemented with bile acids: 0 (Con), 400 (BA400), 800 (BA800), and 1200 (BA1200) mg/kg, respectively. The results showed that the growth was promoted in fish at the BA800 treatment compared with the control (p < 0.05). Increased enzyme activities and transcripts of gluconeogenesis in the liver were observed, whereas decreased enzyme activities and transcripts of glycolysis, as well as glycogen content, were shown in the BA800 treatment (p < 0.05). The transcripts of bile acid receptors fxr in the liver were up-regulated in the BA800 treatment (p < 0.05). A bile acid supplementation of 800 mg/kg improved the morphological structure in the intestine. Meanwhile, intestinal antioxidant physiology and activities of lipase and trypsin were enhanced in the BA800 treatment. The transcripts of genes and immunofluorescence intensity related to pro-inflammation cytokines (il-1β, il-8, and tnf-α) were inhibited, while those of genes related to anti-inflammation (il-10 and tgf-β) were induced in the BA800 treatment. Furthermore, transcripts of genes related to the NF-κB pathway in the intestine (nfκb, ikkα, ikkβ, and ikbα1) were down-regulated in the BA800 treatment. This study demonstrates that a dietary bile acid supplementation of 800 mg/kg could promote growth, improve glucose metabolism in the liver, and enhance intestinal health by increasing digestive enzyme activity and antioxidant capacity and inhibiting inflammatory response in L. maculatus.

Comparative Mitogenome Characterization of Cryptic Asian Seabass (Lates calcarifer) in Captivity within Peninsular Malaysia

Lates calcarifer is one of the most commercial species in the world. Yet, phylogenetic relationships among this cryptic species remain unclear despite its significance in the fishery sector. The first report on bifurcation of captive Lates calcarifer in Peninsular Malaysia (PM) inferred from complete mitochondrial genome was discussed in the present study. Two mitochondrial genomes (mitogenomes) of Lates species were sequenced and assembled. The mitogenome length was 16,627 bp and 16,515 bp for K4 and S15, respectively. The majority of PCGs in both species exhibited the common initiation marker ATG codon and ended with termination marker TAA codon. Also, the incomplete termination codon T/TA was found in both species. Most AT-skew and GC-skew values observed in the protein-coding genes (PCGs) across the two samples were negative. The phylogenetic analysis based on 13 protein-coding genes by Maximum-Likelihood tree displayed two lineages from different regions which were from Myanmar/Indian waters (K4) and Southeast Asia/ Australian waters (S15). The striking genetic distance values between both specimens indicated 13 PCGs were suffering purifying selection. This study offers significant information for future analyses of evolutionary relationships among the numerous and taxonomically puzzling perciform fishes.