ISSN: 2278-778X Research Article www.ijbio.com International Journal of Bioassays (IJB) 249 REPLACEMENT OF ARTEMIA NAUPLII WITH DIFFERENT ALTERNATIVE DIETS FOR LARVAL STAGE DEVELOPMENT AND SURVIVAL OF GIANT FRESH WATER PRAWN, MACROBRACHIUM ROSENBERGII (DE MAN) Shailender M, Krishna PV, Suresh Babu CH Acharya Nagarjuna University, Nagarjuna Nagar, Andhra Pradesh, India *Corresponding Author: Dr. M. Shailender, Acharya Nagarjuna University, Andhra Pradesh, India. Received for publication: October 11, 2012; Accepted: November 8, 2012. Abstract: The present study was conducted on Macrobrachium rosenbergii (de Man) larvae to estimate the effectiveness of different diets to replace Artemia nauplii in the feeding system. The study included two experiments performed at pilot scale in 12–l tanks using a recirculating system. Larval stocking density was 100 l–1. After 10 days of feeding by Artemia nauplii, different diets included wet and dry diets (Egg custard, Artemia flakes and Higashi Maru No-3 feed) and de-capsulated Artemia cysts, were tested to replace Artemia nauplii. In a control treatment using only de-capsulated Artemia cysts throughout the complete larval rearing was also included. The results showed that feeding larvae exclusively de- capsulated cysts for the complete rearing cycle was not suitable. When gradually replacing up to 50% of the Artemia nauplii ratio with wet or dry diets, good results in terms of growth, survival and quality of the larvae were obtained, similar to the control treatment receiving only Artemia nauplii. However, immediately replacing 50% of the Artemia nauplii ratio with artificial diets negatively affected larval development. Addition of artificial feed could start from larval stage VI, with about 25% of the Artemia nauplii replaced with artificial diet. Subsequently, the addition ratio could be increased up to 50% from stage VIII to postlarvae stage. Artificial diets should be provided in different particle size ranges based on the acceptance of larvae, larval stage, gradually increasing from 250 to 1000 μm from stage VI to postlarvae stage. The results obtained in the present work may also helpful for the replacement for different diets for economical aspects of the hatchery operations. Keywords: Macrobrachium rosenbergii, Artemia, Larval Rearing, Artificial Diet, Survival INTRODUCTION Freshwater prawn culture has great potential for rural aquaculture, generating considerable employment and income for rural and poor people. Freshwater prawn farming is environmentally sustainable, since it is practiced at low stocking density (New 1995). A majority of seed used for farming of M. rosenbergii comes from hatcheries (Murthy et al. 2004; Phuong et al. 2006). Existing hatcheries in the country are however not producing up to their installed capacity due various constraints. For production of scampi, Artemia nauplii are used as a live food source in the larviculture. Several authors demonstrated that Artemia nauplii are enough to produce M. rosenbergii post larvae (Devresse et al., 1990; Lavens et al., 2000). However, others showed that Artemia nauplii do not completely fulfill the nutritional requirements of scampi larvae during the last larval stages and therefore they recommend the use of supplemental diets like egg custard and pelleted feeds (New, 1995; Valenti and Daniels, 2000). Leger et al. (1987) showed that decapsulated Artemia embryos have 30–50% more energy than newly–hatched nauplii (Instar I). Bengtson, et al., (1991) reported that decapsulated Artemia cysts have a higher energy and nutritional value than live Artemia nauplii. Sorgeloos et al. (1977) also suggested the use of decapsulated cysts as a direct source for fish and crustacean larvae. Subsequent studies demonstrated those decapsulated cysts are a good feed similar to freshly hatched Artemia nauplii for the larvae of marine shrimps Penaeus monodon (Mock, et al., (1980) and freshwater prawn and M.rosenbergii (Bruggeman, et al., 1980). Artemia nauplii have proven to be successful as live food for raising the larvae of many crustacean species, inherent problems, such as the potential introduction of pathogens into the culture system or the high costs of labor and equipment required for preparation. Sorgeloos et al. (1983) noticed that the nutritional quality and physical properties of Artemia nauplii depend on the source and time of harvest of cysts. Most of the hatcheries are dependent on imported Artemia cysts (O.S.I brand: from U.S.A). Murthy et al. (2008) observed that the complete dependence on Artemia as feed not only makes hatchery operations expensive, but also unsustainable. New (1990) noticed that the dependence on Artemia is also a major constraint in the expansion of M. rosenbergii hatcheries and also farming. Hence, there is a need for replacement of Artemia and to look for