shrimpmanual_chapter7%5b1%5d

Chapter 7 – Nutrition and Feeding of Litopenaeus vannamei 
 - 125 - 
Chapter 7 
Nutrition and Feeding of Litopenaeus vannamei in 
Intensive Culture Systems 
by 
Peter Van Wyk 
Elements of a good feeding program 
Feeding is one of the most critical aspects of shrimp husbandry. A good feeding program is 
necessary for shrimp to grow at their maximum potential. Feed represents one of the most 
significant operating expenses for most semi-intensive and intensive aquaculture 
operations. Often feed costs represent the single highest operating expense (50%) for an 
aquaculture enterprise. A well-managed feeding program insures that the feed is utilized 
efficiently. 
 
There are many things that a producer must do to guarantee a successful feeding program: 
 
1) Feed a high quality diet that is formulated to meet the nutritional 
requirements of the shrimp and is manufactured from high quality, digestible 
ingredients; 
2) Use only prepared feeds that are attractive, palatable and appropriate in size 
for the shrimp; 
3) Maintain feed quality by utilizing proper feed storage and handling 
procedures; 
4) Present the feed in quantities and frequencies that are appropriate for the 
number and size of the shrimp in the population being fed; 
5) Distribute the feed evenly over the culture area to ensure that all the shrimp 
have equal access to the feed. 
6) Make timely adjustments to the feeding regime based on water quality and 
the shrimp appetite. 
Nutritional Requirements 
The nutrients required by cultured species can be broadly classified as proteins, 
carbohydrates, lipids, vitamins and minerals. The optimum levels of these nutrients vary 
from one species to the next. 
Protein Requirements 
Protein makes up 65 to 70% of the dry weight of a shrimp, and is a major component of 
muscle. Protein in shrimp diet is the source of amino acids, which serve as building blocks 
for the shrimp’s own proteins. There are 20 different amino acids, but only 10 of these are 
considered to be essential in the diet. The rest can be synthesized by the shrimp from the 
 Chapter 7 – Nutrition and Feeding of Litopenaeus vannamei 
 - 126 - 
10 essential amino acids. Strictly speaking, shrimp do not have a minimum protein 
requirement. Rather, they have minimum requirements for each of the ten essential amino 
acids (Table 7-1). 
 
Table 7-1: Recommended amino acid levels in commercial shrimp feeds, on an as-fed 
basis (after Akiyama and Tan, 1991). 
 
Percent of Feed 
Amino Acid 
Percent of 
Protein (%) 36% Protein 38% Protein 40% Protein 45% Protein 
Arginine 5.8 2.09 2.20 2.32 2.61 
Histidine 2.1 0.76 0.80 0.84 0.95 
Isoleucine 3.5 1.26 1.33 1.40 1.58 
Leucine 5.4 1.94 2.05 2.16 2.43 
Lysine 5.3 1.91 2.01 2.12 2.39 
Methionine 2.4 0.86 0.91 0.96 1.08 
Phenylalanine 4.0 1.44 1.52 1.60 1.80 
Threonine 3.6 1.30 1.37 1.44 1.62 
Tryptophan 0.8 0.29 0.30 0.32 0.36 
Valine 4.0 1.44 1.52 1.60 1.80 
 
The amino acid requirements for shrimp have not been well defined because shrimp do not 
efficiently utilize crystalline amino acids from the purified diets used to study amino acid 
requirements. As a general rule, however, the amino acid requirements of a species closely 
mirror the amino acid composition of their muscle tissue (Lim and Persyn, 1989). The 
amino acid composition of shrimp feeds is largely based on the amino acid composition of 
shrimp muscle (Akiyama, et al., 1991). Feed formulators mix and match different sources 
of protein, each with different amino acid profiles, so that the diet meets the minimum 
requirement for all 10 essential amino acids. The formulator must also take into account 
the digestibility of each of the feed ingredients and the availability of the amino acids. 
Fishmeal is generally considered to be the highest quality protein source because the amino 
acid composition of fishmeal closely matches that of shrimp. For commercial growout 
diets, krill and Artemia meal are better than fishmeal, but they are more expensive. 
However, they are used in larval and maturation diets. 
 
Most commercial shrimp feeds formulated for intensive culture systems contain between 35 
and 50% protein. If the level of protein in the feed is too low, growth rates will be 
reduced. Severe protein deficiencies may actually lead to weight loss if the proteins in 
shrimp muscle tissue are used to maintain other vital functions. Excess protein in the diet 
may also inhibit growth (Lim and Persyn, 1989). The excess protein will be metabolized 
by the shrimp as a source of energy, and nitrogen will be excreted as ammonia. Protein 
requirements are fairly high for postlarvae and small juveniles, but decline as the shrimp 
grow larger. Table 7-2 gives the recommended protein levels for different sizes of shrimp 
in high-intensity culture systems. 
 Chapter 7 – Nutrition and Feeding of Litopenaeus vannamei 
 - 127 - 
Table 7-2: Recommended protein levels for different sizes of shrimp in high-intensity 
culture systems. 
 
Shrimp Size (g) Recommended Feed Protein Level 
0.002 – 0.25 50 % 
0.25 – 1.0 45% 
1.0 – 3.0 40% 
>3.0 35% 
 
Lipids 
Lipids, or fats, are a group of organic compounds that include free fatty acids, 
phospholipids, triglycerides, oils, waxes and sterols. Lipids function as an important 
energy source for shrimp. In addition to their value as an energy source, lipids serve as a 
source for essential fatty acids. Fatty acids are chain-like organic molecules with many 
repeating units. Each “link” in the chain contains a carbon atom. Fatty acids differ in chain 
length and in the degree of saturation (number of double bonds and hydrogen atoms). A 
highly unsaturated fatty acid will have many double bonds, and few hydrogen atoms. 
These fatty acids appear to be important in the structure of cellular membranes. Four fatty 
acids are considered essential fatty acids in shrimp, because they are required in the diet 
and cannot be synthesized from other compounds. The essential fatty acids are: linoleic 
acid (18:2n6), linolenic (18:3n3), eicosapentaenoic acid (20:5n3), and decosahexaenoic 
acid (22:6n3) (Kanazawa an Teshima, 1981). Table 7-3 gives the recommended levels 
essential fatty acids in shrimp diets. 
 
Table 7-3: Recommended fatty acid levels in commercial shrimp feeds (after Akiyama, et 
al. 1991) 
 
Fatty Acid Percent of Feed 
Linoleic Acid (18:2n6) 0.4 
Linolenic Acid (18:3n3) 0.3 
Eicosapentaenoic Acid (20:5n3) 0.4 
Decosahexaenoic Acid (22:6n3) 0.4 
 
 
Phospholipids are compounds consisting of glycerol, fatty acids and phosphoric acid. They 
are important components of cell membranes and play an important role in lipid 
metabolism. Sterols are required by crustaceans as a precursor for maturation and molting. 
 
Lipids are often added to fish diets in the form of fish oil, soybean and sometimes squid oil. 
Table 7-4 gives the recommended lipid levels in shrimp diets for high-intensity culture 
 Chapter 7 – Nutrition and Feeding of Litopenaeus vannamei 
 - 128 - 
systems as a function of shrimp size. The recommended total lipid level in the diet 
decreases with increasing shrimp size. 
 
Table 7.4: Recommended lipid levels for shrimp diets used in intensive culture. 
 
Shrimp Size (g) Lipid Level (%) 
0.002 – 0.2 15 % 
0.2 – 1.0 9 % 
1.0 – 3.0 7.5 % 
>3.0 6.5 % 
 
Carbohydrates 
Carbohydrates serve as an inexpensive energy source in shrimp diets. Starches, sugars and 
fiber are the main forms of carbohydrates. Organisms differ in their ability to use 
carbohydrates as an energy source. Carnivores, whose diets contain high levels of protein, 
tend to use protein as an energy source and often are unable to metabolize carbohydrates 
effectively. Omnivorous and herbivorous fish and shrimp utilize carbohydrates effectively. 
While no absolute carbohydrate requirement has been found for shrimp, carbohydrates in 
the diet can have a “protein sparing” effect for species that