Growth and anabolism of fish are sustained from the energy
supplied fromthe catabolismof dietary protein or energy sources. This
means that the dietary protein requirement of fish is affected by
dietary energy. Many studies have investigated the relationship
between dietary protein and energy in fish feeds. These studies have
indicated that at inadequate energy level, dietary proteinmay be used
as an energy source, whereas at high protein level, a proportion of this
proteinwill be deaminated and the carbon skeleton used as an energy
source (Garling andWilson,1976; Cho and Kaushik,1985). At adequate
energy level, dietary protein can be spared for anabolic functions
(Garling and Wilson, 1976; El-Sayed, 1987)