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The silver pomfret (Pampus argenteus) is a widely distributed and economically important marine fish in the Indo-Pacific. In this study, we acquired the second generation of wild P. argenteus by artificial breeding and further studied the testicular development and ultrastructure of spermatogenesis. The results of gonadosomatic index (GSI) showed the spawning period of this marine fish was from April to June. Besides, through morphological analysis, we found that P. argenteus had an anastomosing tubular testis surrounded by a layer of tunica albuginea, in which spermatogenesis occurred in cysts where the synchronous germ cells were completely surrounded by the cytoplasmic projection of Sertoli cells. Meanwhile, based on submicroscopic characteristics, the germ cells are classified into nine different types. During the ontogenesis of testis, both the early stage of spermatogenesis and sperm were observed in P. argenteus. At sperm maturation stage, different types of spermatozoa and activation of sperms occurred non-synchronously in the tubules. Cytoplasmic bridges also were observed among synchronous germ cells within the cysts, suggesting an interrelated and differentiated relationship among these germ cells.

A cell line (PaF) derived from the fin tissue of silver pomfret (Pampus argenteus) was established and characterized in this study. The cell line has been subcultured for more than 50 times in Dulbecco's modified Eagle's medium (DMEM) containing 15% foetal bovine serum (FBS) since the initial primary culture. PaF cells grew well at temperatures from 24°C to 28°C in DMEM supplemented with 15% FBS. Partial amplification and sequence analysis of the cytochrome B gene indicated that PaF originated from silver pomfret. Cytogenetic analysis demonstrated that the modal chromosome number was 48. A significant cytopathic effect was observed in PaF cells during viral haemorrhagic septicaemia virus (VHSV) infection, and the VHSV replication was confirmed by qRT-PCR and viral titre assays. In contrast, PaF cells were resistant to red-spotted grouper nervous necrosis virus infection. Moreover, PaF cells could respond to VHSV and lipopolysaccharide treatments, as indicated by the expression of immune-related genes, TLR5 and TLR9. In conclusion, the establishment of PaF cell line will provide an appropriate in vitro tool for the study of mechanisms of pathogen-silver pomfret interaction.

In fish, growth and development are mainly regulated by growth hormone/insulin-like growth factors. Common aquaculture practices subject fish to stress. To investigate the effects of acute stress on growth-related genes in cultured fish, the expression of growth hormone receptors (ghr1 and ghr2), insulin-like growth factor binding proteins (igfbp1, igfbp4, and igfbp5), preprosomatostatin I and II (ppss1and ppss2), somatostatin receptors (sstr2 and sstr5), myostatin (mstn1 and mstn2), and glucocorticoid receptors (gr1 and gr2) were examined in Pampus argenteus subjected to handling stress. Plasma growth hormone levels increased significantly and peaked at 12 h and then decreased significantly at 24 h after treatment (P

A feeding trial was conducted in a flow-through system in 1 m3 tanks using seawater to determine the optimum dietary protein requirement of juvenile silver pomfret, Pampus argenteus (Euphrasen). Fish were stocked a density of 12 juveniles per tank. Five semi-purified iso-energetic diets were formulated with fish meal to contain graded levels of 35, 40, 45, 50, and 55% crude protein. Each diet was fed to triplicate groups of fish to apparent satiation twice daily. The growth of fish fed 50% protein diet was not significantly different (P > 0.05) from that of fish fed 45 or 55% diet, but significantly higher than that of fish fed 35 or 40% diet. Feed conversion ratio (FCR) ranged between 1.7 and 2.5%, and 35% protein diet had significantly higher FCR than those of 45, 50 and 55% diets. Protein efficiency ratio of fish fed 55% protein diet was significantly lower than rest of the diets. Fish fed 50% dietary protein showed significantly best apparent net protein utilization. There were no significant differences between the survivals of fish which ranged between 80.6 and 88.9%. Based on the polynomial regression analysis of %weight gain, the optimal dietary protein level for silver pomfret was estimated to be 49%.

The present study was carried out using juveniles of silver pomfret, Pampus argenteus, produced in the hatchery by stripping eggs from spawners collected from the wild during 2004 and 2005 culture period. The experiments carried out during 2004 investigated the efficiency of using salmon feed mixed with cyclopeeze, salmon feed mixed with shrimp meat, salmon feed alone, and shrimp meat alone in the diet using 1 m3 capacity round fiberglass tanks in three replicates for each treatment with flow-through seawater. The results showed that inclusion of shrimp meat in the diet either with salmon feed or alone give significantly high (P

The spawning periodicity of silver pomfret, Pampus argenteus (Euphrasen), was investigated against a background of conflicting evidence on the onset of spawning in this species. Contrary to the existing view that silver pomfret in Kuwait waters begin to spawn in March–April, evidence is presented that indicates a delay in spawning until May. Only an insignificant level of spawning takes place in April which, from the management point of view, may be ignored. The species has a prolonged spawning period extending from May to August in females, although the males mature in April and ripe specimens are encountered in monthly samples until September. There are two spawning peaks, the first one in May and the second in August.

Eleven polymorphic microsatellites were isolated from an important foodfish species, silver pomfret ( Pampus argenteus ). The loci showed different variation patterns in 24 unrelated P. argenteus individuals, with a mean number of alleles of 11.5 and a mean expected heterozygosity of 0.85. Eight of the 11 loci conformed to Hardy–Weinberg equilibrium. All and six of the 11 markers amplified specific and polymorphic products in Chinese pomfret ( Pampus sinesis ) and dark pomfret ( Pamus cinereus ), respectively. These markers should be useful for population genetic analysis and biodiversity studies of P. argenteus and other pomfret species .

The occurrence in the North Sea of a specimen of the white pomfret, Pampus argenteus (Euphrasen, 1788), a mesopelagic fish which is native to the Indian Ocean and particularly South-east Asia and the East China Sea, is described. Other anomalous distribution records for the same species are examined and some possible explanations investigated.