Effects of dietary protein levels on length-weight relationships and condition factor of Clarias gariepinus under floating hapa trial
Feeding trial involving different protein levels on length–weight relationships and condition factor of Clarias gariepinus was conducted in floating hapa system. Fingerlings (average weight, 4.50± 0.01g and average length, 8.0±0.2 cm) were randomly stocked at 20 fish/1m3. Five diets with crude protein: 40.0, 42.5, 45.0, 47.5 and 50.0% were fed to fish at 5% of their body weight for 24 weeks. Each treatment had three replicates. At harvest, fish body weights and total lengths were measured with maximum accuracy and data obtained were analyzed using the formula W = aTLb which was further transformed to linear equation of Log W = Log a + b Log TL. Growth was observed to be positive allometric (b = 3.273) in fish fed 40.0% protein diet while those fed other diets showed negative allometric growth with b values ranging from 1.6473 to 2.6682. The coefficient of correlation(r)was highly correlated (r> 0.9 at p< 0.05) in fish fed 40, 42.5 and 45.0% protein diets. Condition factor ranged from 0.92 to 1.12 with no significant variations (p> 0.05) in all treated groups. Therefore, 40% protein diet was found to produce the best growth in terms of length-weight relation and condition factor.
Keywords: Clarias gariepinus, dietary protein, floating hapa system, length-weight relationships