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Frozen shrimp and finfish are important export products in Sri Lankan economy. Careful evaluation of growth trends and competitiveness of these products is important in further value chain development and sustainable economic profits. The present study examined the growth performance and export competitiveness of frozen shrimp and major finfish exports from Sri Lanka during 2000-2015. Analysis of finfish exports showed that bigeye tuna (Thunnus obesus) and yellowfin tuna (Thunnus albacares) were dominant export products. Compound growth rate analysis (CGR) of frozen shrimp indicated that there was a negative growth rate in terms of both export value (-9.3%) and export quantity (-9.07%) during 2000-2015. Fresh chilled fish, frozen fish and fish fillet and other meat have shown positive growth rates in export value (5.09, 10.24 and 70.10% respectively). However, considerable instability (11.07 and 11.74 in terms of value and quantity) was recorded in fish fillet and other meat. Export competitiveness index (XCl) for fresh/chilled fish, frozen fishand fish fillet showed positive competitiveness (XCl>1) during 2001-2015. Revealed comparative advantage (RCA) for finfish exports have shown strong competitiveness (RCA≥ 4) during 2000-2015. Frozen shrimp exports were weakly competitive (1<RCA≤2) during 2008-2015. Finfish exports have shown significant positive growth (p<0.05) in unit value realisation while frozen shrimp exports have shown non-significant (p>0.05) negative growth in unit value realisation. Expansion of export markets for Sri Lankan seafood products, value addition, compliance with international standards and diversification of shrimp exports are important further steps to sustain the competitive position of Sri Lankan fishery exports.

A 42-day experiment was performed to evaluate the growth performance and feed utilization of Nile tilapia (Oreochromis niloticus) fingerlings fed iso-lipidic diets (5% lipid) contain 17% or 25% of cassava starch extract from fresh root (R starch) or from dry chips (D-starch) at 37% and 30% protein levels. The diets were ie: 37% protein -FM25R17 & FM25D17, 30% Protein- FM15R25 & FM15D25. 144 fish (1.11+0.02g) were distributed in 12 tanks (54 L). Protein level or starch source had no impact on final weight, length, average daily gain, specific growth rate, food conversion ratio, hepato somatic index, viscero somatic index, and Whole-body composition of fish. Protein Efficiency Ratio was not affected by starch source; however, it was significantly higher in diets with low protein content. Apparent Digestibility Coefficient of dry matter was not affected by starch source but was significantly high in low (30%) protein diet. Inclusion of R starch substantially reduced the cost of feed and increased economic profitability. Tilapia fed FM15R25 diet showed similar growth and nutrient utilization to fish fed 37% protein diets and cost of FM15R25 diet was lower than other diets. Therefore, FM15R25 is the best practical diet among the tested diets for Nile tilapia fingerlings.

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Reef fishery plays a very important role in the coastal fishing of Sri Lanka and also there is a belief that some reef fishes provide special health benefits. However, the information available on chemical composition of reef fish is very limited. This study is based on the consumer preference survey conducted through an interview of 60 consumers at three retail markets in Sri Lanka namely Dondra, Matara and Weligama. Proximate composition was also analyzed for three highly consumer preferred reef fish species. A total of 34 fish, representing at least 11 specimens from each of the three fish species were analyzed for moisture, protein, lipid, ash and the total energy content. Gonado-somatic index (GSI), hepato-somatic index (HSI) and condition factor (K) were also calculated from January to April 2012.It was revealed that consumers highly preferred Lethrines olivaceus (Longface emperor) (27%) whereas preference for Epinephelus merra (Honey comb grouper) and Lutjanus rivulatus (Blubber-lip snapper) were 17% and 9% respectively. Two way ANOVA showed no significant difference in the moisture and ash content among three species, but there was a significant difference (p<0.05) in protein and fat content. Highest protein content was in E. merra (89%), while its lipid content was 5-8% (of the dry weight). Three species had condition factors above 1.7, which indicates their relative healthiness, with respect to food and space within the southern coastal waters of Sri Lanka. E. merra had the highest GSI values while L. olivaceus and L. rivulatus had the lowest and intermediate values respectively, which can be related to their gonadal development stage. The HSI was negatively related to total energy of females of E. merra and L. olivaceus, which could be due to energy reservation in liver than in muscles for their reproduction, while in L. rivulatus such a trend was not evident possibly due to prominent lipid storage structures within their body cavity. E. merra had the highest energy content (5.82 kJ g -1 ) and consumers expressed their belief on its suitability for consumption with a view to reduce cholesterol level (80%). D.M.A. Edirisinghe et al./Sri Lanka J. Aquat. Sci. 18 (2013): 27-36