Table 11. Dietary nutritional deficiency, essential amino acid (EAA) and fatty acid (EFA)
EAA/EFA	Deficiency signs/syndrome	Measure
Lysine	Slow growth, high feed conversion ratio, fin erosion	Add lysine supplement or use feed ingredient ingredients of fish and animal origin
Methionine	Slow growth, high feed conversion ratio	Add methionine supplement �
Typtophan	Slow growth, high feed conversion ratio	Use fish meal and fishery by-products in feed formulation
Histidine	Slow growth, high feed conversion ratio, Cataracts in smolts	Use blood meal in feed formulation
Essential fatty acid	Slow growth, fatty liver, increased mortality  �	Add 6�8 % marine fish oil to prevent deficiency in practical diet
Source: NRC (1993)