Department of Aquaculture, Faculty of Agriculture and Natural Resources, An Giang University, 18 Ung Van Khiem Street, Dong Xuyen Wards, Long Xuyen, Vietnam
Department of Animal Nutrition and Management, Swedish University of Agricultural Sciences, P. O. Box 7024, 75007, Uppsala, Sweden
Department of Physical Geography, Stockholm University, 106 91, Stockholm, Sweden
The feeding experiment was conducted to evaluate the efficacy of locally available feed resources for Tra catfish (Pangasianodon hypophthalmus) cultured a series of 21 hapa net cages installed in the earthen pond during a 4-month period. The reference diet contained fish meal as the main crude protein (CP) source, whilst in the seven test diets 20–100 % of the fish meal CP was replaced with CP from local feed ingredients: groundnut cake (GNC), cassava leaf meal (CSLM), sweet potato leaf meal (SPLM), soybean meal (SBM), golden apple snail meal (GASM) and shrimp head meal. There were differences (p < 0.05) among diets in final body weight, total weight gain, daily weight gain, specific growth rate, viscera-somatic weight (VSI%), hepato-somatic index (HIS%) and intra-peritoneal fat (IPF%). The respective values for the shrimp head meal diet were numerically highest, followed in descending order by the reference, GASM, GNC, SPLM, CSLM and SBM diet. Food conversion ratio, fish survival rate, total feed intake, feed utilisation, fish fillet and kidney proportions did not differ among the reference and test diets (p > 0.05). However, the viscera-somatic, hepato-somatic, kidney and intra-peritoneal fat indices differed among treatments (p < 0.05). These data show that fish meal protein can be replaced with protein from locally available plant and animal feed ingredient resources in feed cultured in net cages in pond for Tra catfish fingerlings in effectively compromising growth performance, feed utilisation or carcass traits of fish.