Search

Temperature is a crucial environmental factor that significantly impacts the growth, development, metabolism, and physiological functions of fish. To study the effects of low‐temperature on the gonadal development of silver pomfret (Pampus argenteus), a cold period by gradually lowering the water temperature from 18°C to 9°C was simulated. The results showed that hsp70, hsp90a, and hsp90b were widely expressed in the tissues of P. argenteus, with hsp70 primarily expressed in the pituitary, hsp90a and hsp90b mainly expressed in the lateral. The hsps were involved in the development process of P. argenteus from 1 to 27 days post‐hatching (dph). The expression levels of hsp70 and hsp90b were highest at 17 dph, while the levels of hsp90a were at 25 dph. Under the condition of 9°C, regressed oocyte were observed in the ovaries, the oocyte diameter significantly decreased, and the ovaries degenerated 100% after low‐temperature stress. The expression levels of hsps in the ovaries were significantly higher than in the control group, while the expression levels in the testes were significantly lower than in the control group. Taken together, hsps may regulate the ovarian degeneration under low‐temperature stress. Male fish rapidly completed meiosis and maintained the testes in the prophase of meiosis to resist the low‐temperature stress. [ABSTRACT FROM AUTHOR]

Pampus argenteus demonstrates a preference for Rhopilema esculentum as prey, yet the ramifications of consuming supplemental medusa on fish microbiota and metabolism remain elusive. To elucidate these effects, 300 juvenile fish were divided into two groups: control group (C, given commercial food only) and supplemental medusa (SM) group (given supplemental medusa + commercial feed). After 15 days, fish in the SM group exhibited a significant increase in fatness, the amylase activity in the intestine significantly increased, and the intestinal microvilli were arranged more neatly. The comprehensive approach involving 16S rRNA amplicon sequencing and metabolomics was employed, leading to the identification of five genera within the SM group, namely Lactococcus, Cohaesibacter, Maritalea, Sulfitobacter, and Carnobacterium. Functional prediction analysis of the microbiota indicated that the consumption of supplemental medusa facilitated processes such as glycolysis/gluconeogenesis and amino acid absorption. Metabolomics analysis revealed significant enrichment of 85 differential metabolites, most of them belonging to fatty acids and conjugates. These differential metabolites primarily participated in processes such as amino acid metabolism, fatty acid synthesis, and disease. Notably, the consumption of medusa resulted in a significant reduction in nine lysophospholipids associated with cardiovascular disease and inflammation. Pearson's correlation coefficient analysis revealed associations between specific microorganisms and metabolites, indicating that Cobetia, Weissella, and Macrococcus exhibited an increased abundance in the SM group, positively correlating with apocynin, 12‐Hete, and delta 9‐THC‐d3. The indicator bacteria Psychrobacter reduced in the SM group, exhibiting a negative correlation with cystathionine (a compound involved in glutathione synthesis). Overall, the supplementation of medusa may confer a beneficial effect on the immunity of the fish. This study contributes to the theoretical framework for fish feed development. [ABSTRACT FROM AUTHOR]

The silver pomfret fish Pampus candidus (Previously known as Pampus argenteus Euphrasen) was collected from Iraqi marine waters in the northwest Persian Gulf between April and December 2021, using gillnet and demersal trawling. The lengths and weights of fish were recorded, along with data on the initial maturity length, sex ratio, gonadosomatic index (GSI), Dobriyal index, gonad maturation, development cycle, and absolute fecundity rate. The forked length of female individuals varied from 248 to 281mm, whereas that of male individuals ranged from 124 to 194mm. In July, young fish began to appear. Male individuals had a somehow shorter period of sexual maturity compared to female counterparts. Furthermore, it is noted that males tend to be generally less in size compared to females. The length at first maturity female and male was recorded as 203 and 115mm, respectively. The sex ratio tends to increase for males, and there were two peaks in the rise of the gonadosomatic index and Dobriyal's index, which indicate two periods of spawning activity during June and September. Six stages of fish maturity have been identified, with differences in the size of the eggs. They had a long and continuous breeding season that lasted from May to November, and they spawned by releasing eggs in batches. Notably, they have two distinct reproductive periods: The first during May and June and the second during October and November. The relationship of fecundity with weight was found to be more representative than with length. The document mentions that the silver pomfret spawning and nursery areas are adjacent to the Shatt al-Arab discharge area. [ABSTRACT FROM AUTHOR]

Shukri SM, Setyawan AD, MD Naim D. 2024. Metal concentrations in Silver pomfret Pampus argenteus (Euphrasen, 1788) and its risk assessment in Malaysia. Nusantara Bioscience 16: 13-22. Fish consumption is one of the most important sources of protein in Malaysia. Nevertheless, anthropogenic sources release contaminants, such as metals, which have the potential to accumulate wi thin marine organisms via the food chain. Hence, ingesting fish polluted with metals can be potentially hazardous to human health. This study aimed to ascertain the levels of metal concentrations in the edible tissues of Pampus argenteus (Euphrasen, 1788) inhabiting Malaysian waters to evaluate potential health hazards associated with their use. This study examines the levels of three metals, specifically Cd, Ni, and Pb, in P. argenteus. The samples underwent microwave digestion in a closed vessel to extract metals, which were subsequently analyzed using ICP-OES. The study revealed that the quantities of metals in P. argenteus were primarily Pb, with Ni and Cd following suit. These values ranged from 0.651 mg/kg to 0.001 mg/kg when measured on a dry weight basis. Notably, the samples collected from the Straits of Malacca exhibit a greater concentration of metals than those obtained from the South China Sea region. The tolerable daily intake of P. argenteus from all populations in this study was below the FAO/WHO oral reference dose. The risk assessment results showed that all populations' target hazard quotient was below 1.0. The results indicate that exposure to the metals studied poses a low non-carcinogenic risk and is considered safe for human consumption. This research offers baseline data for evaluating food safety and developing risk management recommendations concerning P. argenteus. [ABSTRACT FROM AUTHOR]

SM, Binashikhbubkr K, Setyawan AD, Md Naim D. 2024. Geometric morphometric divergence of five populations of Pampus argenteus (Euphrasen, 1788) from Malaysian waters. Nusantara Bioscience 16: 1-12. Phenotypic variation in fish may indicate different environmental conditions that affect species' growth and maturation rates and result from genetic factors that allow fish to adapt to different environments. Understanding population structure and dynamics is extremely important for establishing sustainable fisheries. Silver pomfret, Pampus argenteus (Euphrasen, 1788), is an economically important fish species with extensive geographical distribution from the East China Sea to Southeast Asia, Indian Ocean, Arabian Gulf, and the North Sea. It may represent morphologically distinct populations across their range. The main aim of this study is to use geometric morphometric analysis based on physical characteristics to look into the phenotypic diversity of the species across five different populations in Malaysia. Digital images of 260 mature specimens were captured for further analysis. Principle Component Analysis (PCA) and Multivariate analysis (MANOVA) were used in the intra-population analysis based on the transformed distance. At the same time, the Canonical Variance Analysis (CVA) and the Procrustes ANOVA were utilized to determine the inter-population analysis of P. argenteus. The Unweighted Pair Group with Arithmetic Mean (UPGMA) method used to support the analysis has shown that the population is clearly grouped according to homologous body shape. The results show that South, West, and North Coast specimens were grouped while the East Coast and Borneo Island shared in another group. The variations in the body shape of P. argenteus occurred in body depth, caudal region, and head orientation. The findings separated the populations into two main groups representing the marine region to which they belong. This present study is the first report on phenotypic variations of P. argenteus from Malaysian waters utilizing the geometric morphometric method. [ABSTRACT FROM AUTHOR]

In the artificial breeding of Pampus argenteus (Euphrasen, 1788), female fish spawn before male release sperm, which indicates rapid ovarian development. In fish, aromatase is responsible for converting androgens into estrogens and estrogen plays a crucial role in ovarian development. In this study, we aimed to investigate the potential role of brain-type and ovarian-type aromatase to study the rapid ovarian development mechanism. The results showed that cyp19a1a was mainly expressed in the ovary and could be classified as the ovarian type, whereas cyp19a1b could be considered as the brain type for its expression was mainly in the brain. During ovarian development, the expression of cyp19a1a in the ovary significantly increased from stage IV to stage V and Cyp19a1a signals were present in the follicle cells, while cyp19a1b expression in the pituitary gland decreased from stage IV to stage V. To further investigate the function of Cyp19a1a, recombinant Cyp19a1a (rCyp19a1a) was produced and specific anti-Cyp19a1a antiserum was obtained. The expressions of cyp19a1a, estrogen receptors 2 alpha (esr2a), and androgen receptor alpha (arα) were significantly upregulated in the presence of rCyp19a1a. Meanwhile, cyp19a1a was expressed significantly after E2 treatment in both ovarian and testicular tissue culture. Taken together, we found two forms of aromatase in silver pomfret. The ovarian-type aromatase might play an important role in ovarian differentiation and maturation, and participate in E2 synthesis through co-regulation with esr2a. The brain-type aromatase cyp19a1b might be involved in the regulation of both brain and gonadal development. [ABSTRACT FROM AUTHOR]

In the artificial breeding of Pampus argenteus (Euphrasen, 1788), female fish spawn before male release sperm, which indicates rapid ovarian development. In fish, aromatase is responsible for converting androgens into estrogens and estrogen plays a crucial role in ovarian development. In this study, we aimed to investigate the potential role of brain-type and ovarian-type aromatase to study the rapid ovarian development mechanism. The results showed that cyp19a1a was mainly expressed in the ovary and could be classified as the ovarian type, whereas cyp19a1b could be considered as the brain type for its expression was mainly in the brain. During ovarian development, the expression of cyp19a1a in the ovary significantly increased from stage IV to stage V and Cyp19a1a signals were present in the follicle cells, while cyp19a1b expression in the pituitary gland decreased from stage IV to stage V. To further investigate the function of Cyp19a1a, recombinant Cyp19a1a (rCyp19a1a) was produced and specific anti-Cyp19a1a antiserum was obtained. The expressions of cyp19a1a, estrogen receptors 2 alpha (esr2a), and androgen receptor alpha (arα) were significantly upregulated in the presence of rCyp19a1a. Meanwhile, cyp19a1a was expressed significantly after E2 treatment in both ovarian and testicular tissue culture. Taken together, we found two forms of aromatase in silver pomfret. The ovarian-type aromatase might play an important role in ovarian differentiation and maturation, and participate in E2 synthesis through co-regulation with esr2a. The brain-type aromatase cyp19a1b might be involved in the regulation of both brain and gonadal development.

Our study delved into exploring the bacterial profiles and volatile compounds during the fermentation of two distinct fish sauces, i.e., Larimichthys polyactis (LP) and Pampus argenteus (PA), and a co-occurrence network was employed to investigate the underlying relationship between flavor and microorganisms. The pH (6.97–5.66) remarkably declined while the total volatile basic nitrogen (TVB-N, 92.36–116.55 mg/100 mL) and amino acid nitrogen (AAN, 104.49–638.68 mg/100 mL) contents gradually rose with the fermentation of LP and PA samples. Bacterial community analysis revealed that Psychrobacter was the dominant genus before LP fermentation, and its relative abundance was gradually occupied by Staphylococcus after 7M. The most dominant genus before PA fermentation was Photobacterium , while Virgibacillus emerged as the predominant genera of PA samples after 7M. Seven main volatile compounds made salient contributions (VIP ≥1.0, ROAV ≥1.0) to the flavor of LP- and PA-fermented samples, respectively. Among them, three typical genera (Tetragenococcus , Streptococcus and Staphylococcus) and four specific genera (Tetragenococcus , Psychrobacter , Vagococcus and Lactobacillus) were the core microorganisms contributing to flavor compounds in LP and PA samples, respectively. Therefore, acquiring insight into the microbes responsible for key flavors in multi-variety fermented fish sauces could provide essential indicators for optimizing commercial fermentation processes. • LP- and PA-fermented fish sauces at different stages were prepared. • 7 and 7 flavor compounds made salient contribution to the LP and PA fish sauces. • Microbial profiles exist differences among two samples and four fermentation stages. • Co-occurrence network model elucidated microbe correlations with volatile compounds. • 3 and 4 core genera were well related to key flavor compounds in LP and PA samples. [ABSTRACT FROM AUTHOR]

Silver pomfret, an economically important fish species, encounters significant challenges posed by copper pollution in wild and culturing environment. High level of copper has the potential to accumulate in aquatic organisms over prolonged exposure periods. The extracellular matrix, which is highly susceptible to copper, encompasses various proteins, among which tenascin (TN) might play a crucial role in potentially regulating copper-induced apoptosis. To investigate this hypothesis in fish, we initially identified six TN family members in silver pomfret, namely TNCa , TNCb , TNR , TNXB , TNXBa and TNN. Phylogenetic analysis showed four gene subfamilies, namely TNC, TNR, TNN, and TNX, through comparative analysis with TNs from seven other teleost fish species. Subsequently, we analyzed transcriptome of silver pomfret under copper stress and found differential expression of TN family genes under varying levels of copper stress, particularly TNCa. KEGG enrichment analysis demonstrated a significant enrichment of TN downstream pathway, specifically the Pi3K-AKT signaling pathway. RT-qPCR results indicated up-regulation of TNs and apoptosis inhibition-related genes and down-regulation of apoptosis promotion-related genes within this pathway. Hence, we speculated that TN inhibits copper-induced apoptosis by modulating this particular pathway. To further validate this hypothesis, we established a copper stress cell model using a silver pomfret kidney cell line (PaK) and utilized siRNA to knock down TNCa expression within this cellular model. Comparing RNAi-Cu group to NC-control group, we observed significantly reduced cell viability and intensified apoptosis signals in the former. Additionally, RNAi-Cu group displayed down-regulation of apoptosis inhibition-related genes and up-regulation of apoptosis-related genes in Pi3K-AKT signaling pathway compared to NC-Cu group. These findings indicated that TN might be able to inhibit copper-induced apoptosis through Pi3K-AKT signaling pathway. Ultimately, this study offers foundational knowledge for exploring heavy metal toxicity effect on fishes and some references for utilization of copper in parasite control. [Display omitted] • We initially identified six tenascin family members in silver pomfret. • Phylogenetic analysis revealed four tenascin subfamilies in silver pomfret. • TN can inhibit copper-induced apoptosis through the Pi3K-AKT signaling pathway. [ABSTRACT FROM AUTHOR]

Silver pomfret (Pampus argenteus) is an important economic fish for aquaculture industry in China and Southeast Asian countries.The relationship between twelve morphological traits of P. argenteus were studied at different growth stages [60-, 90-, 120-, and 360-days post hatching (dph)] by usingcorrelation, path analyses, and multiple linear regression tools. The results showed that coefficient of variation of the body weight and trunk length traits remained stable and at a high level across all age groups (all above 20%), while other traits were the opposite. The body length and tail length traits had great direct effect on the body weight of P. argenteus at the first three growth stages (60, 90, and 120 dph). However, body length and body height traits had great direct effect in 360 dph, and the direct effect coefficient of caudal length was negative, indicating that the trait had a negative effect on body weight. Multiple linear regression analysis between morphological traits and body weight indicated that R2 was greater than 0.84 across all age groups (P < 0.05).The optimal multiple linear regression equations, as determined with stepwise regression, were constructed with morphological traits as independent variables and body weight as dependent variables.These results elucidated the linear relationship between the body weight and various main morphological traits of P. argenteus at different growth stages. In actual production, during mass selection of P. argenteus with body weight as the main objective, the recommended as auxiliary selection traits were the body length, body height, tail length, and caudal length traits. These results can provide a reference basis for the measurement of target traits for the selective breeding of new varieties of P. argenteus. [ABSTRACT FROM AUTHOR]

Nocardia seriolae , a widespread opportunistic pathogen, has the ability to infect various economically farmed fishes, leading to prolonged disease courses and high mortality rates. In our current study, we focused on the silver pomfret (Pampus argenteus) and examined the liver, spleen, and kidney tissues at three specific N. seriolae infection phases: control (0 day), L group (infection for 5 days), and H group (infection for 15 days). Utilizing HE staining, we observed typical granulomatous nodules displaying stratified concentric layers, including caseous necrotic cells, epithelioid cells and multinucleated giant cells, fibroblasts and fibrocyte envelopes. The TUNEL assay revealed a significant presence of apoptotic cells concentrated within the renal nodules. Following the infection, there was a noticeable increase in AKP, ACP, and LZM levels in all tissues, while LPS exhibited a consistent decline. Through combined analysis of WGCNA and KEGG pathways derived from the tissue transcriptome, we identified several highly enriched pathways, such as the PI3K-Akt signaling pathway and p53 signaling pathway, in all three tissues. Key DEGs from these pathways underwent further investigation through RT-qPCR. In comparison to the control group, the L group exhibited up-regulation of genes associated with biosynthesis catabolism, whereas genes related to immune response, apoptosis, and ion transport displayed down-regulation. Interestingly, the H group showcased a stark reversal of this trend. To validate these DEGs expressions in vitro, we established a Pampus argenteus spleen cell line (PaS). By evaluating the invasion metrics of NS into PaS, we determined an optimal invasion threshold of 105 CFU/ml. The TUNEL assay demonstrated a notable presence of apoptotic signals in the 5 h and 7 h treatment groups. JC-1 assays indicated a gradual decline in membrane potential starting from the 3-h mark. As the duration of treatment increased, RT-qPCR and IHC findings highlighted an initial up-regulation followed by a subsequent down-regulation of genes associated with biosynthesis catabolism. In contrast, genes related to innate immunity displayed up-regulation, whereas genes related to adaptive immunity and ion transport exhibited an initial surge followed by a gradual decrease. Additionally, genes inhibiting apoptosis showed down-regulation. In conclusion, these findings provide valuable insights into the apoptosis mediated by N. seriolae in piscine hosts. These effects are potentially attributed to the increased expression of ion transport-related genes. Moreover, our study sheds light on the intricate molecular mechanisms underlying piscine immunological responses throughout the entire infection timeline, offering promising opportunities for disease control. • N. seriolae infection caused quintessential granulomatous nodules. • Many apoptotic cells centrally located within the renal nodules. • The weakening of metabolism declined acquired immunity after N. seriolae infection. • We constructed the spleen tissue cell line of silver pomfret. • The apoptosis caused by N. seriolae might be related to ion transport. [ABSTRACT FROM AUTHOR]

A 20 days feeding experiment and 15 days reversed feeding experiment were conducted to study the growth of Pampus argenteus juveniles under different feeding strategies. A total of 900 juveniles (an average ± SD, 5.88 ± 0.98 cm and 5.69 ± 0.64 g) were divided into three feeding groups and the experiments run in triplicate. Each experimental tank contained 1000 L of water and each group was fed to satiation four times a day. Three groups were constructed: group A (fed with 100% jellyfish), group B (fed with 100% Yubao 5# feed), and group C (fed with 50% jellyfish and 50% Yubao 5# mixed feed). The remaining 200 healthy individuals respectively in groups A and B were removed following the 20 days feeding experiment and subjected to 15 days of reverse feeding, resulting in group A' (fed with 100% Yubao 5# feed) and group B′ (fed with 100% jellyfish). Yubao 5# feed is 42% protein while live jellyfish larvae with a 1–2 cm umbrella diameter contain approximately 10% protein content. After 20 days, the results showed similar growth performance in terms of weight gain and specific growth rate (P > 0.05) for group A and B, indicating that the P. argenteus juveniles were able to survive on a jellyfish diet. However, the juveniles in group C showed significant (P < 0.05) weight gain and specific growth rate (8.96 ± 0.77 and 4.739 ± 0.572, respectively) over the same culture period. Serine protease (SP) was selected to study the detoxification mechanism of P. argenteus that were fed on jellyfish, and the SP enzyme activities, mRNA, and protein expression under different culture conditions were analyzed to illustrate the detoxification effect of SP protease on jellyfish toxin. The results showed that the highest SP enzyme activities occurred in the kidneys, liver, stomach, lateral capsules, caecum, and intestine (P < 0.05), with enzyme activity in the order group A > group C > group B, group A > A', and group B′ > B (P < 0.05). The highest enzyme activity of 188.91 UL /L was observed in group A when P. argenteus were fed jellyfish exclusively for 20 days (P < 0.05). The results indicate that jellyfish were the main contributors to the changes observed in the SP mRNA, protein, and enzyme activities. Our results indicate that P. argenteus juveniles can survive when feeding only on jellyfish and grow more rapidly when 50% jellyfish is added to the feed than when fed with jellyfish or Yubao 5# feed alone. SP enzymes, which are sensitive to jellyfish, play an important regulatory role in the digestion and decomposition of jellyfish by P. argenteus , and the kidneys are the most important organ for the detoxification and regulation of jellyfish toxin. • Pampus argenteus juveniles are able to maintain growth by feeding only on jellyfish. • Addition of jellyfish to feed significantly improves the growth of Pampus argenteus. • Serine protease in the kidney of Pampus argenteus plays a detoxifying role against jellyfish toxins. [ABSTRACT FROM AUTHOR]

Understanding the mechanisms of lipid transport and metabolism in fish is crucial to enhance dietary lipid utilization. Here, fatty acid translocase (CD36) gene was characterized in silver pomfret (Pampus argenteus). The open reading frame of silver pomfret cd36 gene was 1395 bp, encoding 464 amino acids. The silver pomfret CD36 protein contained typical transmembrane regions and N-glycosylation modification sites, and was localized to the cytomembrane. The cd36 gene was ubiquitously expressed in all tested tissues, with the highest expression observed in brain tissue. In vivo , both fasting and short-term high-fat feeding could increase cd36 expression in intestinal tissue. In vitro , cd36 expression was induced by palmitic acid, oleic acid, linolenic acid, eicosapentaenoic acid (EPA), and docosahexaenoic acid treatment in intestinal tissue. Furthermore, dual-luciferase reporter assay results indicated that peroxisome proliferator-activated receptor gamma (PPARγ) could enhance cd36 promoter activity, and the co-expression of cd36 and pparγ was observed in EPA-incubated intestine, suggesting that EPA may regulate the expression of cd36 via PPARγ to maintain the homeostasis of intestinal lipid metabolism in silver pomfret. These results highlighted the crucial role of CD36 in silver pomfret, and suggested that the cd36 expression may be regulated by PPARγ. This study could contribute to a greater understanding of lipid metabolism and the development of effective strategies for nutrient requirements in fish. [Display omitted] • CD36 was identified and characterized in silver pomfret. • Silver pomfret CD36 possessed typical transmembrane receptor characteristics. • Silver pomfret cd36 expression was regulated by nutritional status and LCFAs. • EPA might regulate Silver pomfret cd36 expression via PPARγ pathway. [ABSTRACT FROM AUTHOR]