EFFECTS OF LIVE FOODS, ARTIFICIAL FEED AND THEIR COMBINATION ON GROWTH AND SURVIVAL OF AFRICAN CLARIID CATFISH (HETEROBRANCHUS-LONGIFILIS VALENCIENNES, 1840) LARVAE

In both laboratory and outdoor culture environments, Heterobranchus lo ngifilis larvae fed a combination (Diet 1) of mixed live zooplankton a nd artificial diet grew significantly longer (p<0.01) than those fed m ixed live zooplankton (Diet 2) or an artificial diet (Diet 3; 0.5 mm p article size) alone. Those fed the zooplankton grew significantly long er (p<0.01) than the larvae fed the artificial diet. Larvae fed Artemi a nauplii (Diet 4) were significantly longer (p<0.01) than larvae fed Diets 1, 2 and 3 on both the 6th and 11th days of culture. The overall best biomass (8.3 g) was obtained by larvae fed Diet 1 followed by Di ets 2 (4.9 g), 3 (2.1 g) and lastly 4 (2.0 g). At day 11, the best ind ividual growth (3.4 cm, standard length; 0.47 g wet weight) was record ed among larvae fed Diet 4, followed by 2.1 cm and 0.13 g for Diet 1, 1.5 cm and 0.06 g for Diet 2 and 1.3 cm and 0.04 g for Diet 3. Specifi c growth rates were 4.8%, 34.8%, 28.3% and 23.1% for larvae fed Diets 4, 1, 2 and 3, respectively. The decrease in survival from day 6 to 11 was 98% to 79%; 76% to 65%; 73% to 61% and 28.25% to 4.25%, for diets 2, 1, 3 and 4, respectively. In the outdoor culture, larvae fed Diet 1 grew significantly longer and had a higher SGR than those fed Diets 2 or 3.