Lipids, are the generic name for fat soluble compounds found in living matter, broadly classified as fats, phospholipids, sphingomyelins, waxes and sterols. Dietary and tissue lipids are important in the nutrition of shrimp. Dietary lipids are a concentrated and highly digestible source of energy, and are a source of essential fatty acids necessary for normal growth and survival of all animals. Dietary lipids serve as a carrier of fat soluble vitamins and provide other compounds, such as sterols and phospholipids, which are essential for the normal metabolic function of shrimp (Akiyama et al., 1992).

Lipids, such as phospholipids and sterols, are important structural components of cell and organelle membranes. Phospholipids help in maintaining the fluid and flexible nature of membranes. Sterols are important in the synthesis of steroid hormones and the hormone-like prostaglandins. Dietary lipids also serve as an "attractant" and can affect the texture of the feed. Recommended lipid levels for commercial feeds range from 6% to 7.5% (Akiyama et al., 1992).

• Fatty acids
  
• Phospholipids
  
• Cholesterol