ABSTRACT
Length-weight relationship of fish is very important, because it helps to predict weight from length measurement. Two hundred and forty fish samples of O. niloticus, having body weight value between 10.01-12.11 g and total length size ranging from 8.0 - 9.7 cm were hand-sexed with Methylene blue solution. Fish samples were randomly selected and introduced into twelve (12) 100 liters plastic bowls measuring 76 cm in diameter and fed on formulated diet, twice daily for 90 days with plankton inclusion at 5 % body weight. The experiment which was bi-factorial, was conducted in triplicates (at stocking densities of 10, 20, and 30) using four crude protein rations thus: (20, 25, 30, and 35 % and labeled A-D). Each crude protein ration at different stocking densities had influence on the growth of fish samples, resulting in negative allometric growth as observed from the regression coefficient "b = 0.68" which was less than the value of 3. This type of growth pattern implied that fish grew more in length than in weight, thus making them more slender as they increased in length. Data realized from the interaction between crude protein rations at different stocking densities revealed that a diet of 30 % crude protein at a stocking density of 20 gave rise to the highest body weight value (16.72±6.52a) at a total length of (11.69±2.93a). Alternatively, a protein ration of 20 % at a stocking density of 10 fish samples resulted in the second best result with a body weight of (12.86±1.67a) having a total length of (10.27±1.24a) as recommended. |
