Abstract:
The nutritional requirements of protein, fat, carbohydrate, mineral mix and cellulose for the optimum growth of mud carp (average weight: 5.4±0.2 gm./fish) were studied. The L18(6×36) table of orthogonal design method was employed to formulate eighteen diet combinations. Feeding experiments were conducted in 70×45×40 cm aquaria of 126 L in capacity under the following conditions: 1) water flow maintained at 62 L/hr; 2) water temperature averaged 30.8±1.2℃; 3) dissolved oxygen being 5.11 ±1.25 mg. O2/L and pH, 7.8±1.0. The data of the experiments were analysed with the method of analyses of variance and the multiple method of Tukey's Q procedure.The results of feeding experiment show that the effects of nutients on the specific growth rate, condition factor and body protein gain ratio ranked in the following order: proteincarbohydratemineral mixfat. Thus, protein (P0.005) and carbohydrate (P0.025 except condition factor) were found to be the main nutrients, while the effects of fat and mineral mix were not so pronounced in the present experiment. The nutritional requirements for the optimum growth were protein: 0.70—0.80 gm., fat: 0.10 gm., carbohydrate: 0.50 gm. with an ingredient of 14% minerl mix and 17% cellulose in the diet per 100 gm. fish (wet weight)/day.Although fat composition and moisture content fish boty show correlation with the fat content of the food, the nutritional protein levels do have a stronger effect on the fat and moisture contents of the body (P0.025 and P0.01 respectively.) When the fish was fed with increasing protein levels, body fat increased but body, moisture decreased. There wasa negative correlation between body fat (Y) and moisture (X), the; formula being Y=60.3063—0.7643X. Fat and moisture together amounted to 78.33± 0.25%. in the fish.The maintenance nitrogen for metabolism was found to be 14 mg. N/100 gm. fish (wet wright)/day obtained from the experiments with protein-free diet.