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Docosahexaenoic acid (DHA) is the principal constituent of a variety of cells especially the brain neurons and retinal cells and plays important role in fetal brain development, development of motor skills, and visual acuity in infants, lipid metabolism, and cognitive support and along with eicosapentaenoic acid (EPA) it plays important role in preventing atherosclerosis, dementia, rheumatoid arthritis, Alzheimer’s disease, and so forth. Being an essential nutrient, it is to be obtained through diet and therefore searching for affordable sources of theseω-3 polyunsaturated fatty acids (PUFA) is important for consumer guidance and dietary counseling. Fish is an important source of PUFA and has unique advantage that there are many food fish species available and consumers have a wide choice owing to availability and affordability. The Indian subcontinent harbors a rich fish biodiversity which markedly varies in their nutrient composition. Here we report the DHA and EPA content and fatty acid profile of 39 important food fishes (including finfishes, shellfishes, and edible molluscs from both marine water and freshwater) from India. The study showed that fishesTenualosa ilisha,Sardinella longiceps,Nemipterus japonicus, andAnabas testudineusare rich sources of DHA and EPA. Promotion of these species as DHA rich species would enhance their utility in public health nutrition.

Summary The spawning periods, sex ratio and length at first maturity were determined for six commercially important finfish species collected from Oman's industrial trawl fishery. During 1 year of monthly sampling, biological data were collected on 5586 fish. ancova was used to compare the length–weight relationships between sexes. There were sex-specific differences in length-weight relationships for three of the six species examined. One serranid, Epinephelus diacanthus, and a sparid, Pagellus affinis, had sex ratios significantly different from the expected ratio of 1 : 1. Size–frequency data revealed more male fish in the larger size classes for E. diacanthus, P. affinis and Nemipterus japonicus. Data on the development of female gonads and Gonado-somatic Index (GSI) revealed that the six species spawned at different times of the year. With the exception of female E. diacanthus, all fish had low GSI values during the onset of the summer monsoon period in June. The proportion of immature vs mature fish in the sample differed among species. For two species, Lethrinus nebulosus and Cheimerius nufar, more than 40% of the fish sampled (both sexes) were immature. Approximately 33% female and 41% male P. affinis were also immature. Management options such as temporal and area closures are discussed in light of the large number of immature fish caught by the fishery.

An investigation lasting 36 weeks was carried out on the frozen storage ( - 20C) behavior of surimi prepared from the fish pink perch ( Nemipterus japonicus ). Total volatile base nitrogen (TVBN), trimethylamine (TMA), peroxide value (PV) and total plate count (TPC) values of surimi increased gradually from 3.5 ± 0.1 to 5.60 ± 0.17 mg%, 0 to 2.8 ± 0.2 mg%, 0 to 0.8 ± 0.3 meq/kg and 5.25 ¥ 10 4 to 9.58 ¥ 10 4 cfu/g, respectively, during frozen storage but were within the acceptable limit. Nonprotein nitrogen (NPN), free alpha-amino nitrogen and surimi whiteness increased from 13.63 ± 0.09 to 22.35 ± 0.2 mg%, 0 to 8.55 ± 0.02 mg% and 61.83 to 63.48 degrees, respectively, with the passage of time. Moisture, crude protein, total nitrogen (TN), pH and gel strength of surimi decreased from 78.50 ± 0.14 to 76.55 ± 0.02%, 17.72 ± 0.18 to 14.57 ± 0.01%, 2.84 ± 0.02 to 2.14 ± 0.02%, 7.20 ± 0.1 to 6.05 ± 0.09, and 237 to 97.43 g ¥ cm, respectively, during frozen storage. The surimi was acceptable at the end of the 36 week storage period.

Summary Weight–length relationships were estimated for 20 Lessepsian fish species of the Iskenderun Bay, namely, Apogon nigripinnis, Apogon queketti, Callionymus flamentosus, Cynoglossus sinusarabici, Dussumieria elopsoides, Etrumeus teres, Fistularia commersonii, Lagocephalus spadiceus, Lagocephalus suezensis, Leiognathus kluzingeri, Nemipterus japonicus, Oxyurichthys petersenii, Saurida undosquamis, Sillago sihama, Siganus luridus, Siganus rivulatus, Sphyraena chroysotaeina, Stephanolepis diaspros, Upeneus moluccensis and Upeneus pori. All regressions were found to be significant for all species. This study presents the first estimation of weight–length relationships for six species (A. queketti, E. teres,F. commersonii, L. suezensis, Nemipterus randalli, and S. luridus) inhabiting coastal areas of the northeastern Mediterranean Sea.