Performance of Nile tilapia (Oreochromis niloticus, linnaeus, 1758) fry fed on egg yolk and powdered fry meal.
Abstract
Aquaculture production is responsible for 50% of the global fishery production. Fishmeal is the preferred protein ingredient in aquaculture feed and contributes significantly to the variable production cost in the aquaculture industry. However, decreasing fishmeal supply relative to demand and increasing costs threaten the sustainability and growth of the aquaculture industry. The way to sustain the industry is to remove or reduce the use of fishmeal. This study was carried out to determine the effect of replacing powdered fry meal with egg yolk on the growth performance and nutrient utilization parameters of the Nile tilapia fry., Statistically, no significant difference in average body length was observed among fry feed on different diets (F (2, 9) = 0.12, P > 0.05, one way ANOVA), Significant differences existed in weight gain of the fish fed on the different diets (p < 0.05, ANOVA) with fish fed on fry meal having the highest value (0.47 ± 0.34) followed by those feed on the mixture (0.39 ± 0.29) and then Egg yolk (0.32 ± 0.26). There was no significant difference also in the nutrient utilization parameters, apart from the Specific Growth Ratio (SGR) which was significantly different between the two diets (F (2, 6) = 0.065, P < 0.05, One way ANOVA). The results show that egg yolk can be a feasible alternative to fishmeal, although it has very many competing uses and it has a negative effect on the water quality of the culture system.