1. Improving the quality of Tiger Prawn (Penaeus monodon) through seaweed (Enteromorpha intestinalis) based diet Kunal Mondal, Subhra Bikash Bhattacharyya*, Rajrupa Ghosh*, Sufia Zaman*, Madhusudan Das**and Abhijit Mitra* Department of Marine Science, University of Calcutta, 35 B. C. Road, Kolkata 700019, India *Attached to Department of Oceanography, Techno India University, EM-4, Sector V, Salt Lake, Kolkata 700091, India **Department of Zoology, University of Calcutta, 35 B. C. Road, Kolkata 700019, India Correspondence: kunalmondal1985@yahoo.com Enteromorpha intestinalis Family: Chlorophyceae Characters: Solitary or gregarious, mostly attached, sometimes remain in free-floating condition. Sub-intestiniform, unbranched, tubular, cylindrical. Cell irregular and chloroplasts with 1-2 pyrenoids. Importance: Rich in astaxanthin and hence used in fish feed preparation. Rich in protein Used as manure due to rich content of trace elements. Bali Island Fig. 2 Map showing the culture location Study Design 1.To screen E. intestinalis from Sundarban mangroves for its carotenoid (astaxanthin) content in relation to shrimp nutrition. 2.To prepare shrimp feed with inclusion of seaweed as an ingredient. 3.To evaluate the effect of E. intestinalis diet on shrimp body pigmentation. 4.Standardization of seaweed cum shrimp culture technology as alternative livelihood for island dwellers of Sundarbans. Methods 1.Collection and processing of plant material: Live and healthy E. intestinalis were collected from seaweed culture pond located at Bali Island (22 o 04'35.17'' N latitude and 88 o 44' 55.70'' E longitude) and the collected materials were washed, dried and processed to make powder. 2. Diet preparation and experimental shrimp farming: Diets were formulated and the culture experiment of P. monodon was conducted during April to December 2012 at Bali Island of Indian Sundarbans (Fig. 2) 3. Analysis of carotenoid content: The carotenoid content was analyzed seasonally according to the spectrophotometric method outlined by Schuep and Schierle, 1995. Its value in % was converted to ppm level for easy interpretation of data. Results Table 1: Seasonal variation in astaxanthin content of Penaeus monodon muscle tissue SeasonsExperimentalControl Pre-monsoon17.62 ± 1.26 a 15.21 ± 1.12 b Monsoon20.71 ± 0.77 a 16.96 ± 0.53 b Post-monsoon23.47 ± 1.34 a 18.22 ± 1.23 b *Figures with different superscripts in the same row are significantly different (p<0.05) Conclusion and outcomes 1.We conclude from the present study that red colour after cooking was markedly darker in the shrimp fed E. intestinalis diet. 2. This may be a significant development in commercial aquaculture of tropical Sundarbans, because it suggest that good results can be achieved by supplementing diets with natural astaxanthin compared to the expensive ones. 3. This can pave the avenue of small scale aquafeed industry in the present geographical locale. Introduction Several macroalgae are widely used in fish diets and there are number of studies into their effects that have been reviewed by Nakagawa and Montgomery 2007. In many instances, the inclusion of algae in feed formulations has resulted in improved pellet quality, higher feed intake, improved feed efficiency, better growth performance and higher animal product quality (in terms of higher pigmentation). On this background, the present study is an attempt to evaluate macroalgae inclusion in Penaeus monodon diet and its effect on body pigmentation. The green filamentous macroalga Enteromorpha intestinalis is rich in carotenoid astaxanthin (112- 186 ppm of dry weight) and is widely available from Sundarban mangrove delta (Fig. 1) Fig. 1 Enteromorpha intestinalis habitat