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Summary Two bycatch reduction devices (BRDs): a juvenile and trash fish excluder device (JTED) and a square-mesh panel (SMP), were tested in the Persian Gulf shrimp fishery from a small-scale shrimp trawler in October–November 2012. Each device was alternatively tested by using a small-mesh cover net to retain individuals that escaped the BRDs. Three valuable fish species—tigertooth croaker (Otolithes ruber), silver pomfret (Pampus argenteus) and silver sillago (Sillago sihama)—were selected for detailed analyses. Average escapement rates by number for commercial species in the trawl nets with either JTED or SMP were calculated as 24% and 33%, respectively. There were significant differences in escapement rates for Otolithes ruber and Sillago sihama between JTED and SMP (p

Summary This study investigated the effects of elevated dietary levels of vitamin E (α-tocopherol) on growth performance, proximate composition and fatty acid profiles of juvenile silver pomfret, Pampus argenteus. Three semi-purified experimental diets were formulated to contain 49% protein and 16% lipid. High docosahexaenoic acid (DHA) tuna oil was added to the diets to supplement DHA. A graded level of vitamin E (0-, 50-, and 100 mg kg−1) was added to experimental diets 1 to 3, respectively. Analyzed vit. E levels were 155.2, 195.3 and 236.4 mg kg−1 in diets 1, 2 and 3, respectively. The experiment was conducted for 12 weeks with juvenile silver pomfret (29.6 ± 7.6 g) using a flow-through system consisting of nine 1-m3 tanks. Each treatment had three replicates and fish were stocked at the rate of 20 m−3. Growth performance and feed utilization parameters of fish fed diets 2 and 3 were significantly (P 0.05). Although whole body protein levels were not influenced by the dietary vit. E levels, whole body lipid in fish fed diet 2 was significantly higher than in fish fed the other diets. The whole body vit. E levels in fish fed diet 2 (22.6 mg kg−1) and diet 3 (24.1 mg kg−1) were significantly (P

Length–weight relationships were estimated for four marine species, namely Pomadasys kaakan (Cuvier, 1829), Pampus argenteus (Euphrasen, 1788), Scomberoides commersonnianus Lacepede, 1801 and Euthynnus affinis (Cantor, 1849) in the Gulf of Oman (Konarak, Iran). During nine cruises, samples were collected at 20‐miles distance from shoreline by 3 panel drift gill‐nets with 120 mm mesh size, 8–9 m height and 0.5 hanging ratio in autumn and winter 2016.

Summary This study investigated the effect of high-dose vitamin C supplementation on growth, tissue ascorbic acid concentrations and physiological response to transportation stress in juvenile silver pomfret, Pampus argenteus (initial average weight 6.2 ± 0.2 g). Three practical diets were formulated to contain 100 (control), 450 and 800 mg ascorbic acid/kg diet, respectively, supplied as l-ascorbyl-2-polyphosphate. Each diet was fed to triplicate groups of fish in circular tanks (3 m o, 1.5 m depth) (60 fish/tank) for 9 weeks. Growth did not change significantly with dietary vitamin C levels, although an improvement tendency with an increase in vitamin C supplementation was observed. Ascorbic acid concentrations in the liver and muscle of fish fed diets containing graded levels of vitamin C were positively correlated with dietary levels of this vitamin. Tissue ascorbic acid concentrations significantly increased with increasing vitamin C supplementation. After 9 weeks, the fish were subjected to transportation stress for 4 h to determine the influence of high vitamin C supplementation on the physiological response to this stressor. Serum cortisol, glucose and lactate levels significantly increased in stressed fish. Serum cortisol and glucose concentrations after stress were significantly higher in fish fed the control diet (7.91 μg L−1 and 0.80 mm, respectively) than in the other groups. However, there were no significant differences in serum cortisol and glucose levels after stress between the 450 and 800 mg kg−1 diets. No significant change could be found in serum lactate levels after stress among the different treatments. In conclusion, the dietary administration of high doses of vitamin C could reduce stress in silver pomfret and increase the survival of fish under stress conditions.

Summary The silver pomfret (Pampus argenteus) is a commercially important species native to the Indo-western Pacific area. In the present study, the genetic structure of five P. argenteus populations from the Arabian Sea, Bay of Bengal, and South China Sea were investigated using sequences of the mitochondrial cytochrome c oxidase subunit I (COI) gene. All populations showed high levels of haplotype diversity (h) and low levels of nucleotide diversity (π). Phylogenetic trees indicated that the haplotypes could be divided into three clusters, indicating the geographic distribution of the five populations. Analysis of molecular variance (amova) indicated the intra-region variation among these populations to be highly significant. The average pairwise differences and Fst values among the three regions were also found to be significant. These results suggest that P. argenteus in these regions has strong geographic genetic structure. The present results provide new information for the genetic assessment, fishery management, and conservation of this species.

This study investigated the effects of varying dietary levels of decosahexaenoic acid (DHA) on growth performance, proximate composition and whole body fatty acid profiles of juvenile silver pomfret, Pampus argenteus. Triplicate groups of fish (30.55 ± 0.08 g) were fed diets containing 5.2%, 9.31% and 13.38% DHA (% of total fatty acids) or 0.85%, 1.52% and 2.18% DHA on dry diet weight for diets 1, 2 and 3 respectively. Survival was not affected by dietary DHA levels. The growth performance and feed utilization parameters of fish fed diets 2 and 3 were significantly (P 0.05). Whole body lipid and fatty acid profiles were influenced by dietary DHA levels. Significantly higher n-3 fatty acids particularly DHA, DHA:EPA(eicosapentaenoic acid) ratios and n-3:n-6 ratios were observed in fish fed diets 2 and 3 compared to those fed diet 1. Better growth performance and higher whole body DHA:EPA (2.31, 2.29) ratios and n-3:n-6 ratios (2.17, 2.12) observed in fish fed diets 2 and 3, respectively, suggests that silver pomfret juveniles have a higher requirement for n-3 fatty acids, notably DHA for optimum growth and survival.

Summary Whole body and egg essential amino acid (EAA) composition of silver pomfret, Pampus argenteus, was determined to estimate their dietary requirements using A/E ratios as an indicator. Ten adult fish (sex ratio 1 : 1) were sampled each month from Kuwaiti waters for a 1-year period (November 2007 to October 2008). There was no significant difference (P > 0.05) between the whole body amino acid (AA) composition of males and females except for glutamic acid and serine. There were no significant differences (P > 0.05) between the contents of leucine, methionine, phenylalanine and threonine in whole body and eggs. However, arginine, isoleucine and valine contents in eggs were significantly higher than those of whole body, while lysine and histidine in whole body was significantly higher than that of eggs. Among non-essential AAs, cystine, tyrosine, alanine, and serine content in eggs were significantly (P

Summary Proximate and fatty acid composition of wild silver pomfrets, Pampus argenteus, were studied in Kuwait waters for a period of 1 year (November 2007–October 2008) to see whether there were any seasonal compositional differences between males and females. Ten adults (five males, five females) were sampled each month during (i) Pre-spawning (March–May), (ii) Spawning (June–August), (iii) Post-spawning (September–November), and (iv) Winter (December–February). Both sexes had significantly (P 0.05) in total saturated fatty acids (SFA), PUFA, EPA (eicosapentaenoic acid), DHA (docosahexaenoic acid) or n-3/n-6 ratios between respective males and females in different seasons. Livers in males had significantly (P

Summary Silver pomfret, Pampus argenteus, were collected by fishing with drift gillnets on one spawning ground in Kuwait waters during 1998–2000. Fish size frequency, sex ratio, maturation cycle, spawning frequency, fecundity and egg weight were assessed. The length–weight relationship differed between sexes whereby females were significantly bigger than males. Spawning started in mid-May and continued until early October. During this time the water temperature ranged from 26.0 to 32.8°C, salinity was ≅ 39.0‰ and water depth ranged between 5 and 12 m. Large females spawned earlier than young spawners and the overall percentage of males during the spawning period was 70.3%. Spawning occurred after 13.00 h, with peak spawning between 15.00 and 18.00 hours during outgoing tide. Mean daily spawning frequency amounted to 63.2%. Spawning activity was found to be associated with the lunar cycle and spawnings were concentrated during the first and third quarters of the moon period, indicating a semilunar reproduction cycle. It was concluded that a female would spawn at least six times during the season. No change was observed in relative fecundity during the peak spawning season (June–August). Average relative batch fecundity was 176.3 eggs g−1 somatic weight (SW), corresponding to a relative total fecundity of 1058 eggs g−1 SW, which is 1.5 times higher than estimates obtained from counting the standing stock of oocytes. Bigger fish produced heavier eggs and the egg weight decreased as the spawning season progressed. Based on gonadal cycles, oocyte size frequency distribution and total fecundity, we concluded that silver pomfret is a multiple batch spawner with indeterminate fecundity.

The silver pomfret Pampus argenteus (Euphrasen) is a new candidate for aquaculture and there is not much information available on its larval rearing. Investigations carried out using microalgae alone in the culture system for the initial feeding of the silver pomfret larvae showed that Chlorella, Isochrysis and Nannochloropsis without rotifers are not conducive to the survival of newly hatched larvae. At 6 days after hatching (DAH), a maximum survival of 3% (1.8 ± 1.69%) was observed with Isochrysis followed by Nannochloropsis (0.35 ± 0.21%) and Chlorella (0.25 ± 0.21%). All control larvae died at 6 DAH without microalgae. Further investigations using the above microalgae with rotifers and a mixture of these same microalgae with rotifers showed that significantly higher (P

Summary The reproductive activities of the silver pomfret, Pampus argenteus (Euphrasen), in Kuwait waters were investigated from March 1996 to February 1998. Observations on the seasonal distribution of maturity stages and variations in seasonal fluctuations in the gonadosomatic index (GSI) confirmed recent findings that the spawning period begins in May. The species has a prolonged spawning period in the females extending from May to August, whereas the males mature in April and ripe specimens were encountered in monthly samples until September. The recruitment pattern confirmed the one breeding season. There are two spawning peaks, the first in May and the second in August. Variations in GSI relative to fish length indicated that females and males are most fecund at about 24.5–26.4 cm and 20.5–22.4 cm length classes, respectively. The males mature earlier than females, at a minimum size of 12.5–14.4 cm, while the females mature at 20.5–22.4 cm. The oocyte diameter-frequency distribution suggests a serial rhythm of spawning. Fecundity ranged from 28 965 to 455 661 and correlated positively with: (a) standard length (P < 0.006); (b) ovary weight (P < 0.001); and (c) body weight (P < 0.001), and negatively with egg size (P < 0.003).

Genetic divergence and phylogenetic relationships among Parastromateus niger (Bloch), Pampus argenteus (Euphrasen) and Pampus chinensis (Euphrasen) were investigated by examining the electrophoretic patterns of nine enzymes and sarcoplasmic proteins. Among the 16 loci detected, four were polymorphic in P. niger and seven in P. argenteus. The allele frequencies of 16 loci were estimated to calculate the genetic distances (D). The average D value among the species increased in proportion to the level of taxonomic category. The relationship estimated by genetic markers accorded well with that estimated from anatomical characters. The three species were clearly divided into two distinct groups at a D value of 6·51.