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Digital, BACKGROUND: There is evidence that children with high cardiorespiratory fitness and normal body mass index (BMI) have less risk of non-communicable diseases (NCDs), however limited research was undertaken in Omani children. Therefore the aims of the present study were to describe body composition and physical fitness of a large cohort of Omani school children of both genders, and to investigate the effects of weight status on physical fitness. METHODS: Three hundred and fourteen Omani school children aged 9 to 10 years old took part in anthropometric assessments, body composition and fitness tests, including handgrip strength, the basketball chest pass, broad jump, 20-m sprint, four 10-m shuttle agility, 30-s sit-up, and multistage fitness test (MSFT). RESULTS: Obese boys and girls performed worse than normal-weight children in sprint, agility and endurance. In addition, fitness measures in the overweight group and underweight groups were not significantly different from other groups, except a better handgrip strength and poorer MSFT in overweight compared to normal weight girls, and poorer agility performance in underweight girls compared to the three other groups. CONCLUSIONS: Most fitness measures are lower in obese Omani children, which suggests that they will be more at risk of developing NCDs later in life., Ciencias Médicas y de la Salud

Data from five field surveys carried out along the shelf in the 20-250m depth range and historical data on artisanal fishery were analyzed. A positive linear relationship between the demersal fish biomass and the shelf area was pronounced for a certain (intermediate) stratum only: 50-100m. No statistical link was found for the strata above it (25-50m) and beneath it (100-150m and 150-250m). The pronounced one was associated with the low boundary of the oxygen minimum zone impinging on the shelf. Annual landings of demersal fishes in the region with the largest shelf area exceeded landings in the region with the smallest area by as much as 1.6 times. The ratio of small pelagic to demersal fish landings decreased as a factor of 10, from small to large shelf areas.

Interdecadal changes in oxygen depletion, with a special reference to artisanal landings of large pelagic fishes, were analysed. Data from 53 expeditions incorporating 29,043 vertical profiles of temperature and 2114 of dissolved oxygen implied an increase in temperature of 1.2 °C over the past 50 years in the upper 30 m layer of sea water during the south-west (summer) monsoon. The thermal stratification of the water column increased and the oxycline shoaled from 153 m in the 1960s to 80 m in the 2000s. Concentration of dissolved oxygen

The Sultanate of Oman has a long established traditional shark fishery, which has experienced increased demand in recent years due to the shark fin trade. Despite the long history of the fishery in Oman and neighbouring countries, few studies have been undertaken to determine the biological characteristics of the fishery or its ability to withstand this increased exploitation. The present study was undertaken as a first step to remedying this situation. A total of 47 species was confirmed from Oman's coastal waters, of which 44 occurred in commercial landings. However, landings were dominated by eight species—Rhizoprionodon acutus, Iago omanensis, Carcharhinus sorrah, Loxodon macrorhinus, C. macloti, C. limbatus, Sphyrna lewini and C. falciformis. The species composition of landings varied along the coast and also with season. Brillouin Index values indicated that species diversity was greatest in the Muscat area, followed closely by Musandam. The Al-Wusta region displayed the lowest diversity. The occurrence of two uncommon shark species, Chaenogaleus macrostoma and Echinorhinus brucus, was of interest, as was the recording of a juvenile Carcharhinus galapagensis, extending its northern range in the Indian Ocean considerably.

The objective of this study was to identify the key variables affecting export performance at the firm level and draw the policy implications necessary to enhance Oman fish exports. The methodology adopted is inspired from the international marketing literature, which postulates that export performance is determined by both internal factors, under the control of the firm, and external factors. Empirically, the study used an econometric model and a firm survey data to investigate the link between export intensity, defined as the proportion of export sale to total sale and 4 sets of firm-level specific factors: (1) firm size and competencies, (2) management characteristics, (3) management perceptions and attitude, and (4) marketing strategy. Results show that both the age and firm size, measured by the number of years in business and the number of employees, had no significant effect on export performance. Managers' education level, previous work experience, commitment to exporting activities, dive...

Competition in both local and international markets for the food business requires the development of differentiated products in order to meet the demand of more quality-stringent, health-conscious, and attribute-oriented consumers. The objective of this study is to evaluate consumers' preferences for value-added fish products in Oman and identify the most important attributes that are preferred by consumers. Such information is of value to the fish processing companies that are looking for profitable business opportunities in local or international niche markets. The study uses a conjoint analysis method to estimate consumer total utility for value-added fish products on the basis of four attributes: form of the product, package size, method of cooking and price. A sample of 200 consumers is selected in 4 major supermarkets in the Muscat region to conduct the conjoint experiment. Results of the conjoint analysis show that the most important attribute in the purchasing decision of the average con...

We developed microsatellite markers for Scomberomorus commerson, and use these in a population genetic study of this species from the Arabian Peninsula. Samples were taken from six sites within four geographic regions: Iran (Arabian Gulf), two sites in northern Oman (Gulf of Oman), two sites in southern Oman (Arabian Sea) and Yemen (Gulf of Aden). A total of 26 markers were developed. Of these, five produced polymorphic PCR products which amplified all six populations. These five markers were used to assess genetic differentiation from 50 individuals at each site. Genetic differentiation, as measured by the fixation index, Fst or Φst, was determined to estimate stock structure. The results identified two genetic stocks, one restricted to one locality (Dhofar) in the Arabian Sea, the other widespread with sufficient gene flow between all four regions to prevent regional genetic differentiation from occurring. Almost 99% of the genetic variation was within populations (p < 0.001). It is however advisable to consider additional, more conventional stock structure methods to determine management strategies as conventional measures of stock structure operate at ecological rather than evolutionary time scales, unlike genetic methods based on neutral markers and genetic drift.

Female Rhizoprionodon acutus were found to mature between 62 and 74 cm total length (L T ) whereas males matured between 63 and 71 cm L T . The L T at 50% maturity was 64·3 cm for females and 64·7 cm for males. Litter size varied from one to six embryos, and was positively correlated with maternal L T . Female embryos outnumbered males by a ratio of 2·3:1. The size at birth was c. 37 cm L T . Full-term embryos and post-partum females were observed during all seasons although their occurrence was highest in spring. Spermatozoa were rarely recorded in the oviducal gland. indicating that this species does not store sperm. It was not possible to generate maturity curves for lago omanensis but it was evident that females matured by the time they reached 35 cm and males were mature by 31 cm L T . This species displayed a clearly defined reproductive cycle with parturition occurring primarily in spring, after a gestation period of c. 1 year. Maximal embryo size was 19 cm L T while maximal litter size was 24 embryos. The oviducal gland appeared to act as a seminal receptacle and it appeared that females may utilize these stores by not mating every year.

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.

The status of the kingfish resource of Oman has been assessed using a per-recruit model noting that there are differences in growth and mortality between the sexes (amongst other parameters). It is estimated that at the current fishing mortality rate the spawning biomass per-recruit for females is 16% and that of males is 27%, indicating that the fishery is overfished, with a high chance of recruitment failure in the future. A number of management scenarios, based on minimum size limits and closed seasons were evaluated for this fishery in order to determine which of the scenarios would increase spawning biomass per-recruit without compromising yield per-recruit harvest rates to levels which may lead to socio-economic hardship amongst fishers. It has been shown that closed seasons and minimum size limits may be the most effective current means of achieving these objectives and it is proposed that a closed season, coupled with a minimum size of 45 cm (FL) for both sexes, be implemented each year from the 1 March to 30 April. This would increase spawning biomass per recruit to 29% for females and 40% for males, when compared to an unfished state and over the long-term.

Age and growth parameters were determined for the kingfish ( Scomberomorus commerson ) at six locations in the Sultanate of Oman. During 2 years of sampling, 1244 kingfish were collected, from which 962 sagittal otoliths were sectioned and read. The fishery is characterized by a prevalence of 0+, 1+ and 2+ year classes, which made up approximately 90% of the total fish collected. Maximum fork lengths, weights and ages for all sexes combined were 166 cm, 40.4 kg and 20 years, respectively. Sex specific differences were evident in length, weight and growth. Growth parameters show that female S. commerson ( L ∞ = 140.44, K = 0.309, t 0 = −1.501) grew at a slower rate but reached a greater asymptotic length than male fish ( L ∞ = 118.80, K = 0.595, t 0 = −0.730). There were significant differences in growth between regions with Ash-Sharqiyah recording the greatest asymptotic length ( L ∞ = 172.82) and Al-Wusta the lowest ( L ∞ = 122.596). Fish from Al-Wusta also grew at a much greater rate ( K = 0.796) than those from the other five regions. A comparison of VBGF values using length frequency data and age at length data at one region, Muscat, revealed differences in all three growth parameters. Catch curves reveal large differences in total mortality ( Z ) between geographic regions, with the highest recorded at Al-Batinah (1.321 year −1 ) compared with 0.405 year −1 at Muscat. Large discrepancies in age structure, growth parameters and annual mortality between regions suggest overexploitation of this species may have already occurred in places like Al-Batinah and Dhofar. However we recommend that mortality estimates ( Z , M and F ) be used with caution until catch curve data for different fishing gear is made available.

Patterns of reproduction and spawning were determined for the kingfish (Scomberomorus commerson, Lacepede) in two oceanographic regions of the Sultanate of Oman. During 2 years of sampling, 1264 fish were purchased from fishermen at landing sites along the Arabian Sea and the Gulf of Oman. Sizes of males and females were similar in both regions but more females were caught along the Gulf of Oman than along the Arabian Sea coast. Females matured at a significantly smaller length and about 2 months earlier than males in both regions. For both sexes, the fish collected along the Arabian Sea matured approximately 10 cm smaller and 6 months earlier that those of the Gulf of Oman. Analysis of the reproductive stages and gonosomatic index revealed a single yearly reproductive cycle beginning in February and ending with a single spawning period in May–June, just prior to the onset of the summer oceanographic regime. Reproductive stages and growth also indicated that 40% of the landings along the Arabian Sea is composed of fish before their first reproduction (Stage I) whereas along the Gulf of Oman, only 25% of the fish were caught before entering active reproduction. Several indicators suggest that kingfish stocks are under intense pressure and that management of this species should be implemented rapidly if they are to remain sustainable.

In an attempt to initiate seafood biotechnology in the Sultanate of Oman, Middle East, using underutilized fish, fish burgers from two different formulas were developed and the quality and storage stability were evaluated during storage at −20°C for 3 months. Quality and storage stability were evaluated through total aerobic and coliform bacterial count, peroxide value, protein solubility, and color. Total aerobic bacteria were reduced significantly (P

Traditional fish burgers are made mostly with added starch but fail to meet consumer expectations of eating quality characteristics. Improved formulations, however, can offer a new marketing position in the area of processed fish products. Promising functional ingredients that can improve organoleptic properties include milk protein, citrus pectin, and bovine gelatin. The large deformation properties of these burgers were identified using compression testing and specific attributes were related to the overall acceptability of the product on the basis of a hedonic scaling method. The quality of the burgers was further manipulated by introducing additional ingredients to the formulation, e.g., soya protein, κ-carrageenan, frozen vegetables, and dried fruits. Distinctive upper and lower bounds of the values of hardness, firmness, adhesiveness, and the ratio of inflectional to maximum stress were defined in relation to optimum sensory acceptability of the product.

The effect of solar radiation upon netting twines maintained under ambient conditions was investigated. Netting twines examined during the study were polyamide (PA) continuous filaments. These included 40 untreated grey twines (controls), 40 that were coated with a coal tar film to reduce UV radiation penetration of the fibres (treated), and 40 untreated green coloured twines. The last acted as a secondary control group. All twines were exposed to 780 h of direct solar radiation after which each was examined for breaking strength and extensibility. Results indicated that exposure of netting twines to solar radiation decreased breaking strength over time ( P

The paper investigates structural changes to the fish marketing system on Masirah Island, its performance during the period 1996 to 2003, and the implications on pricing efficiency and prospective market development. Data was derived from field interviews of fishers and traders, discussions with processing plants managers, site visits, and attendance at market operations on the Island. Results indicate that the marketing system was influenced by the emergence of two potential institutional changes that had bearings on market structure, namely the European ban on fish imports from Oman and improved access to the Island. The previously dominant oligopsony structure declined as a result of weak operation of the processing companies during the past seven years and the entry of a growing number of small-scale traders. Current data indicate that price discovery through auctions gradually overtook oligopsony single price agreements. The survey shows that the fish marketing system on Masirah Island is pointing to...

The Al-Batinah coast is home to around 35% of the Sultanate of Oman's artisanal fisherfolk, who account for 28% of national landings by traditional means. Over the last 10 years, the region has experienced a general decline in its fishery with a consequence of socio-economic disturbance and increased fishing pressure. The present study was undertaken to gain base line socio-economic information upon the region and to examine the industry's structure and co-management strategies. Fisherfolk (mean age: 44.4±8.77 {SD}) were from large families (avg. 12.4), educationally challenged (1.10±2.58 yr formal education), and had limited opportunity for alternative employment. Mean crew size of fishing vessels was 1.86±0.63 (SD) and two different systems were employed for calculating crew earnings. Average income per person was approx. US$ 5000 per annum although there was significant disparity in income distribution between villages. Traditionally, fisherfolk have employed the Senat Al-Bahar (“code of the sea”), in efforts to distribute and manage coastal fisheries. However, change in fishery management, away from local, to a more centralised style, has undermined the effectiveness of this system. This has resulted in alterations in fisherfolk behaviour, with some employing illegal mesh sizes, poaching and fishing in prohibited areas.

The effect of frozen storage on the physiochemical, chemical and microbial characteristics of two types of fish sausages was studied. Fish sausages developed (DFS) with a spice-sugar formulation and commercial fish sausages (CFS) were stored at −20 °C for 3 months. Fresh DFS contained 12.22% lipids and had a 3.53 cfu/g total bacteria count (TBC) whereas, CFS contained 5.5% lipids and had a 4.81 cfu/g TBC. During storage, TBC decreased significantly (p 0.05) in CFS. A peroxide value (PV) was not detectable until week four and eight of storage in CFS and DFS, respectively. The salt-soluble proteins (SSP) level was stable in DFS but in CFS it declined significantly (p 0.05) in both sausage types. This study showed that the effect of storage at −20 °C on fish sausages characteristics varied between formulations and depended on the ingredients of fish sausages.

A survey of fishing gears used in the traditional kingfish fishery along the Gulf of Oman coast of the Sultanate of Oman revealed significant differences in the type of gear and mesh size of nets used by fishers. In two regions of the coast, Al-Batinah and Muscat, different fishing gears (trolling, hooks and line, drift nets, set nets) were used in almost equal numbers, and the dominant mesh size of the nets ranged between 7 and 12 cm. In two other regions (Musandam and Ash-Sharqiyah), most fishing was with a single gear: either set nets or drift nets of large mesh size (>12 cm). An analysis of the maturity stages of the 778 fish landed indicated that, in these waters, females matured at a fork length (80.4 cm) smaller than males (84.7 cm). Further, significantly more females than males were caught in the two regions in which small-meshed nets and a higher diversity of gear types were used. Analysis of the reproductive cycle revealed a single spawning period, peaking in May/June, corresponding with a drop in gonadosomatic index and the appearance of post-spawning fish in the population. Length distribution and analysis of length at first maturity indicated that up to 90% of the fish captured were immature, adding to the risk of growth-overfishing in the two central regions of the coast studied. Improved fishery regulations are proposed and discussed. INTRODUCTION The kingfish Scomberomorus commerson (Lacepede) is one of the keystone species of the traditional fisheries along the Gulf of Oman. Since the introduction of fisheries statistics in Oman in 1988, landings of the species have fluctuated widely, but in recent years, a progressive tenfold decline in the number and biomass of landed kingfish has necessitated an urgent multidisciplinary study of the species (Al-Oufi et al., 2002). Understanding the spawning cycle of commercially exploited species is often an important consideration in the establishment of management strategies for their sustainable