ISSN: 2572-3103
Koroi T and Azam K
The change from traditional subsistence to semi-intensive is leading to an increase in the demand for aquaculture feeds. The culture of freshwater prawn, Macrobrachium rosenbergii in Fiji as protein source and source of income for small-scale farmers is important. However, due to the unavailability and high cost of feed ingredients and formulated feeds, the supply and quality of feeds for aquaculture development is restricted. In addition, the lack of information on cost-effective channels to deliver feeds to farmers has contributed to the poor production and profitability. A nutritional study was conducted to evaluate growth performance of M. rosenbergii fed iso-energetic, low cost formulated diets, using locally available ingredients in ponds for 124 days. Two formulated (MBM+MM+CP-diet 1 and FM+Wht-diet 2) and two commercial (Crest tilapia pellet-diet 3 and Pacific prawn pellet - diet 4) diets were fed. The study indicated no significant differences for weight gain and survival rate (P ≥ 0.05). It was observed that diet 2 induced highest growth rate while the lowest FCR (0.97 ± 0.02) value was obtained for the same diet. The survival of prawns ranged between 83.43 mm ± 5.55 and 89.26 mm ± 0.40%. The highest prawn production was obtained with diet 2 at 0.16 kg/m2. The economic analysis of M. rosenbergii production showed that diet 2 was the least expensive (FJ$0.53) to produce 1 kg of prawn as compared to the commercial diets (Pacific Prawn feed -FJ$0.89 and Crest Tilapia feed - FJ$0.69). Therefore, this study suggests that M. rosenbergii growth was slightly improved when using the formulated diet 2 although the highest survival rate (89.26 ± 0.40%) was obtained from the formulated diet 1. Diet 2 may be recommended to the farmers for monoculture of M. rosenbergii in ponds in comparison to both commercial diets in Fiji.