Fatty acids are important substances that maintain biological functions within the body and provide energy. There are various classification methods for fatty acids. Among them, based on the length of the carbon chain, they can be divided into short-chain fatty acids, medium-chain fatty acids, and long-chain fatty acids. Additionally, according to their saturation level, they are classified as saturated fatty acids, monounsaturated fatty acids, and polyunsaturated fatty acids.

Vitamin C (also known as ascorbic acid) is a water-soluble vitamin that plays a crucial role in the growth, immunity, and stress resistance of aquatic animals. However, similar to humans, many fish and crustaceans lack the ability to synthesize vitamin C on their own because they lack the key enzymes necessary for vitamin C synthesis in their bodies.

In aquaculture, extruded feed and hard pellet feed are two main types of feed. They have distinct characteristics in terms of processing techniques, nutrient utilization, farming outcomes, and economic benefits.

The effect of arginine on animal production performance is mainly manifested in its influence on feed intake. Relevant studies have shown that adding a certain level of arginine to the diet can increase the daily feed intake of broilers. Adding 884 mg/kgL of arginine to the diet can significantly increase the average daily feed intake of laying hens during the laying period.

Isoleucine (Ile) was first discovered by Ehrlich in 1904. Later, it was extracted from the pancreatic trypsin hydrolysates of various proteins and it was found that although its chemical composition is the same as that of leucine, its physical and chemical properties are quite different. After research, its structural formula is a-aminobeta-methylvaleric acid, and it has been confirmed to be an amino acid distinct from leucine.