A fabricated modified single screw fish feed extruder was used to extrude formulated floatable fish feeds from obtainable available feed ingredients. They were fed to 225 Clarias garienpinus (mean weight of 56 4.22 g) for 120 days in order to compare their nutritional values with that of a commercial feed. The fishes were first acclimatized for a period of 48 hours under laboratory condition. The weight of the fishes were taken every two weeks and recorded in comparison with the commercial feed (Durante) which served as the control. At the end of the feeding trials, the fishes were weighed, sacrificed and analysed for whole body composition, haematological status and proximate analysis. At the end of the feeding trial, Treatment 1 had the highest mean values of growth and nutrient utilization indices on Clarias garienpinus at standard deviations of 260.77 g (45.59%), 2.01%, 1.92 and 52.10% for the percentage of weight gained, specific growth rate, feed conversion ratio and feed conversion efficiency of the experimented fishes respectively when compared with the commercial feeds (Control) that had mean values of 416 g (71.36%), 2.18%, 1.20 and 83.33%. Treatment 4 had the lowest weight gained with mean values of 99.67 g (17.77%) 1.67%, 5.02 and 20.00% respectively. The white blood cell of the fishes in Treatment 1 had a high value of 6600 when compared to that of the Control which had a value of 7500. Treatment 1 (T1R1) experimented on Clarias garienpinus, gave the highest values of growth performance and nutrient utilization compared with other treatments in terms of its whole body composition, proximate analysis and haematolgical status. This implies that treatment 1 experimented on Clarias garienpinus, was the best and can be used for feeding fishes since their values are closer to that of the control. There was significant differences in the final weight of fish fed with treatment 1, 3 and 4 (p > 0.05). However, there was no significant difference in treatments 1 and 2.
Nutritional evaluation of protein isolate from rubber seed in the diet of Labeo rohita : Effects on growth performance, nutrient utilization, whole body composition and metabolic enzymes activity
