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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 thatare able to utilize carbohydrates 
efficiently. That is, if carbohydrates are present in sufficient quantity in the diet, the protein 
requirement is reduced. 
Vitamins 
Vitamins are organic compounds that are required in the diet in relatively small quantities 
for normal growth and development. Vitamins are classified as either water soluble or fat 
soluble. The B-complex vitamins are water soluble and are required in relatively small 
quantities. These vitamins function primarily as coenzymes in various metabolic processes. 
Three water-soluble vitamins are required in larger quantities and have functions other than 
coenzymes. These are Vitamin C, inositol, and choline. Vitamin C and choline are often 
added separately, as these vitamins are required in relatively large quantities. The fat-
soluble vitamins are Vitamins A, D, E and K. Fish and shrimp diets usually are fortified 
with a vitamin premix that contains all of the 16 essential vitamins. 
 
The vitamin requirements for marine shrimp are affected by many different factors, 
including shrimp size, age, growth rates and environmental factors (Akiyama, et al., 1991). 
Young juvenile shrimp may require 50% higher vitamin levels in their diets than adult 
shrimp. Shrimp cultured in intensive culture systems typically require much higher vitamin 
concentrations than are required by shrimp grown at low densities. Vitamin deficiencies 
frequently result in symptoms, such as physical deformities, blindness, erratic swimming 
behavior, lethargy and poor growth. The physical symptoms displayed differ, depending on 
which vitamin is deficient in the diet. Vitamin C deficiency is associated with “Black 
 Chapter 7 – Nutrition and Feeding of Litopenaeus vannamei 
 - 129 - 
Death” disease, characterized by melanized lesions of subcuticular tissues. Typically, feed 
manufacturers overfortify shrimp diets with vitamins. This is done for several reasons. 
Detailed information about shrimp vitamin requirements is lacking. Overfortification is 
cheap insurance against crop losses due vitamin deficiencies. In addition, many vitamins 
are unstable compounds that are easily destroyed during manufacture and feed storage. 
Vitamin C, in particular, has a very short half-life at room temperature. Stable forms of 
Vitamin C, such as Stay-C, have a much longer shelf life than the non-stabilized form of 
Vitamin C. Because shrimp are slow feeders, the feed may sit in the water for several hours 
before it is consumed. Significant quantities of water-soluble vitamins may leach into the 
surrounding water before the feed is eaten. 
Minerals 
Minerals are inorganic elements required for various metabolic processes. Minerals 
required in large quantities are called major minerals. These include calcium, phosphorus, 
magnesium, sodium, potassium, chloride and sulfur. Calcium is required for exoskeleton 
formation, muscle contraction and osmoregulation. Shrimp are able to absorb calcium 
directly from the water, and shrimp living in seawater do not need calcium supplements in 
the diet (Davis, 1991). However, diets for shrimp cultured in near-freshwater systems 
should contain up to 2.5% calcium. Higher levels of calcium should be avoided because in 
high concentrations calcium appears to interfere with the bioavailability of phosphorus 
(Davis, 1990). Phosphorus is required for exoskeleton formation and is an essential 
component of phospholipids, nucleic acids, ATP, and many metabolic intermediates and 
coenzymes. Davis (1990) demonstrated that the phosphorus requirement for Litopenaeus 
vannamei was dependent upon the calcium content of the diet, and that in the absence of 
calcium, 0.34% phosphorus was sufficient for normal growth and development. Shrimp 
diets often contain up to 1% dietary phosphorus. Unlike calcium, phosphorus is not 
absorbed in significant quantities from the water and must be supplied in the feed (Davis, 
1991). Calcium and phosphorus are often added to the diet in the form of dicalcium 
phosphate. 
 
Some minerals are required in minute quantities and are called trace minerals. Trace 
minerals include iron, iodine, manganese, copper, cobalt, zinc, selenium, molybdenum, 
fluorine, aluminum, nickel, vanadium, silicon, tin and chromium. The trace minerals are 
generally added to the diet in a mineral premix. Sometimes vitamins and minerals are 
combined into a single vitamin-mineral premix. 
 
Shrimp Feeds 
Formulated Diets 
There is a saying: “Man cannot live on bread alone.” The same is true of shrimp. A diet 
consisting of a single feed ingredient is not likely to be able to provide all of the nutrients 
required for normal growth and development. This is why aquaculturists usually feed their 
 Chapter 7 – Nutrition and Feeding of Litopenaeus vannamei 
 - 130 - 
animals a formulated diet. Formulated diets are mixtures of different feed ingredients 
mixed in set proportions to provide the desired quantities of nutrients. A wide variety of 
different feed ingredients are used in commercial shrimp feed formulations. Common 
ingredients used in commercial shrimp feeds include soybean meal, fish meal, squid meal, 
shrimp head meal (cooked), wheat flour, wheat middlings, lecithin, cholesterol, starch, 
dicalcium phosphate, vitamin and mineral mixes, and binders. 
 
Formulated diets may be either supplemental or complete. Feeds that are applied to 
supplement natural food sources are called supplemental diets. Shrimp grown in ponds at 
very low densities may be able to survive and grow without any supplemental feed input to 
the pond. Under these conditions, naturally occurring plants and animals serve as the food 
source for the culture species. At higher densities, natural productivity is insufficient to 
support the nutritional requirements of the culture species, so prepared feeds must be 
included to supplement the nutrition obtained from natural food sources. Supplemental 
diets rarely meet the nutritional needs of the culture species, but are adequate when natural 
foods are available. Where natural foods are not available, such as in tank-based culture 
systems and high-density pond culture systems, nutritionally complete diets must be 
provided. Complete diets contain all of the essential nutrients in amounts sufficient for 
normal growth and development of the cultured organism. It is also necessary that these 
nutrients must be available in a form that is digestible. Complete diets typically have 
higher protein, vitamin, and mineral levels than supplemental diets. 
 
The majority of commercial shrimp feeds available today are considered to be supplemental 
feeds. Shrimp nutrition is very complex, and the current state of knowledge about shrimp 
nutritional requirements is incomplete. While some very good shrimp diets are available 
commercially, it is doubtful whether any of these can be considered a true complete feed. 
Growth rates of tank-reared shrimp that rely on prepared diets for 100% of their nutritional 
needs do not match the growth rates that are frequently observed in productive pond 
environments. However, the shrimp maintained on these diets develop normally and are 
generally healthy. 
Feed Processing 
Shrimp are benthic feeders, so 
shrimp feeds must be processed into 
a sinking pellet. Most shrimp feeds 
are manufactured either using a 
steam pelleting process or an 
extrusion process. 
 
Steam pelleting uses a combination 
of moisture, heat and pressure to 
form finely ground feed ingredients 
into a dense, tightly bound pellet 
 Figure 7-1: Pelleted Shrimp Feed 
 Chapter 7 – Nutrition and Feeding of Litopenaeus vannamei 
 - 131 - 
(Figure 7-1). The feed ingredients are finely ground and mixed together in the proper 
proportions. Moisture is added and the ingredients are thoroughly blended into a pasty 
mash. The mash is fed into a pelleting mill that uses an auger to compress the mash. Steam 
isintroduced into the pelleting chamber, which causes the starch in the feed mixture to 
gelatinize and helps bind the ingredients together. Binders are often used to complement 
the binding provided by gelatinized starch. The feed mixture is then forced through holes 
in a die plate located at the end of the chamber. The diameter of the pellet is determined by 
the diameter of the holes in the die plate. 
 
Extruded feeds are formed using a similar process, but much higher temperature and 
pressure is generated within the barrel of the extruder. This results in more complete 
gelatinization of the starches contained in the feed ingredients, so additional binders are not 
required. Extruded feeds often are less dense than steam pelleted feeds because rapid 
release of the steam from the feed pellets after they pass through the die plate causes the 
pellets to expand. The extrusion process is often used to create floating pellets, which are 
popular for feeding fish. The extrusion process is typically carried out at a slightly lower 
temperature using formulations with less starch to obtain a sinking pellet. 
Pellet Stability 
Good water stability is important in the preparation of shrimp feeds, regardless of pelleting 
process,. Shrimp are slow feeders and a pellet may sit in the water up to four or five hours 
before it is eaten. To evaluate the feed stability in water, place several pellets in a beaker of 
water. The pellets should remain largely intact for up to four hours. Periodic gentle 
swirling of the water in the beaker can help simulate the effects of water movement on 
pellet stability. Feeds with poor water stability are not efficiently utilized by the shrimp 
and will foul the water. 
Pellet Diameter 
The required diameter of the feed pellets varies depending on shrimp size. Postlarvae and 
young juveniles are too small to eat a formed pellet. Feeds for these shrimp are made by 
grinding a pelleted feed and passing the ground feed through a series of sieves to obtain 
feed particles of a uniform diameter. Because pellet integrity is not as critical an issue for 
ground diets, postlarval and juvenile feeds are frequently manufactured using a cold 
pelleting process. Cold pelleting is less destructive to the vitamins in the feed. Shrimp 
that weigh less than one gram are typically fed ground feeds. Larger shrimp are able to eat 
pelleted diets. Table 7-5 lists recommended particle or pellet sizes for shrimp of different 
sizes. 
 
 Chapter 7 – Nutrition and Feeding of Litopenaeus vannamei 
 - 132 - 
Table 7-5: Recommended pellet diameters for shrimp of different sizes. 
 
Shrimp Size (g) Pellet Diameter 
0.002 – 0.02 400 – 600 µm 
0.02 – 0.08 600 – 850 µm 
0.08 – 0.25 850 – 1200 µm 
0.25 – 1.0 1200 – 1800 µm 
1.0 – 2.5 3/32” pellet (2.4 mm) 
>2.5 1/8” pellet (3.2 mm) 
 
 
When making the transition from one pellet size to the next, it is a good idea to feed a 
mixture of the two sizes of pellets for 5-7 days to allow the shrimp time to get used to the 
larger pellet size before discontinuing the smaller pellets. 
 
Feed Application 
Feeding Rates 
It is critical that feed be applied in the correct amounts and at the correct times throughout 
the culture period. Feed rates must be constantly adjusted to account for shrimp growth, 
mortality and appetite. If the feeding rate is too low, the shrimp will not grow well, and 
overall production will suffer. Underfeeding may also result in cannibalism, especially at 
high densities. Overfeeding also causes problems. Besides being wasteful, uneaten feed 
can contribute to deterioration of water quality in the culture system. The organic material 
in the feed becomes a substrate for heterotrophic bacteria, which metabolize the protein in 
the feed and give off ammonia. Elevated ammonia levels in the water suppress shrimp 
growth and increase the shrimp’s susceptibility to disease. The oxygen demand of these 
bacteria can lead to low dissolved oxygen levels in the system, inhibiting shrimp growth. 
Some heterotrophic bacteria release substances into the water, which can cause the shrimp 
to be off-flavor. Overfeeding causes overall feed conversion values to increase, since 
some of the leftover feed, and inefficient assimilation of the feed that is consumed. 
 
There are many factors that affect the amount of feed the shrimp will eat. Feed consumption 
varies with feed type, shrimp size, water temperature, stocking density, weather, water 
quality and health. Shrimp culturists must take all of these factors into account in order to 
maximize the efficiency of the feeding program. 
 
Temperature has an especially pronounced effect on feed consumption and growth. For L. 
vannamei, feed consumption is optimal when water temperatures are between 27°C and 
31°C (81°F and 87°F). Feed consumption decreases both above and below these 
 Chapter 7 – Nutrition and Feeding of Litopenaeus vannamei 
 - 133 - 
temperatures. Feed consumption 
may be reduced by 50% when 
the water temperature drops to 
24°C (72°F), and ceases 
altogether when water 
temperature drops below 20°C 
(68°F). 
Feed Tables 
Feed tables have been 
developed that give a 
recommended feed rate, 
expressed as percent of 
bodyweight per day (% 
BW/Day), for animals of 
different sizes. As a general 
rule, small animals are fed at a 
higher percentage of their 
bodyweight per day than are 
large animals. This is because 
small animals will generally 
have a higher metabolic rate 
than large animals. Table 7-6 
shows a typical feed table for L. 
vannamei cultured in high-
density tank systems. 
 
To calculate the daily feed allowance for a population of shrimp, multiply the total biomass 
of the shrimp population by the recommended feed rate from the feed table: 
 
 
Daily Feed Allowance = Total Biomass x 
% BW/Day
100 % (7.1) 
The total biomass of the shrimp population is calculated by multiplying the estimated 
number of shrimp in the population by the average weight of the shrimp: 
 
Total Biomass = Total Number of Shrimp in the Population x Average Weight (7.2) 
 
Accurate information about the average weight and total number of shrimp in the 
population is required to correctly calculate the daily feed allowance. The shrimp 
population should be sampled at least every other week to determine the average shrimp 
Table 7-6: Feed Table for High-Intensity Tank 
 Production of Litopenaeus vannamei. 
 
Average Shrimp Wt. 
(g) 
Feed Rate 
(% BW/day) 
<.1 35 – 25 
0.1 - 0.24 25 – 20 
0.25 – 0.49 20 – 15 
0.5 – 0.9 15 – 11 
1.0 – 1.9 11 - 8 
2.0 – 2.9 8 – 7 
3.0 – 3.9 7 – 6 
4.0 – 4.9 6 – 5.5 
5.0 – 5.9 5.5 – 5.0 
6.0 – 6.9 5.0 – 4.5 
7.0 – 7.9 4.5 – 4.25 
8.0 – 8.9 4.25 – 4.0 
9.0 – 9.9 4.0 – 3.75 
10.0 – 10.9 3.75 – 3.5 
11.0 – 11.9 3.5 – 3.0 
12.0 – 12.9 3.25 – 3.0 
13.0 – 13.9 3.0 – 2.75 
14.0 – 14.9 2.75 – 2.5 
15.0 – 15.9 2.5 – 2.3 
16.0 – 16.9 2.3 – 2.1 
17.0 – 17.9 2.1 – 2. 
18.0 – 18.9 2.0 – 1.9 
19.0 – 19.9 1.9 – 1.8 
20.0 – 20.9 1.8 – 1.7 
 Chapter 7 – Nutrition and Feeding of Litopenaeus vannamei 
 - 134 - 
weight. A minimum sample size of at least 30 shrimp should be used to calculate the 
average weight of the population. If there is large variation in size within the population, 
the sample size should be increased to 60 shrimp per sample. Best results are obtained by 
weighing each shrimp in the sample individually after blotting off excess water with a 
paper towel. 
 
Estimation of the total number of shrimp in the population is more difficult. The number 
of shrimp in the population at any given time is equal to the number of shrimp stocked 
multiplied by the fraction of shrimp still surviving at that time: 
 
No. shrimp at time t =Number of shrimp stocked x Fraction surviving to time t 
(7.3) 
 
Survival rates are very difficult to estimate. In tank culture systems, dead shrimp can often 
beremoved from the tank and counted. Although observed mortality is very helpful in 
estimating survival in a tank, population estimates based on observed mortality rates are 
nearly always overestimates of the true number of shrimp. This is because it is very 
difficult to account for all of the mortality, especially for very small shrimp. Some of the 
shrimp may be consumed by other shrimp, while other mortalities may simply escape 
notice. Standardized survival curves based on historical average survival rates are often 
used to estimate shrimp numbers in a population. Survival curves may be linear (assuming 
a constant mortality rate), or may have varying slopes over different portions of the 
growout cycle. Often curves are constructed to reflect heavier mortality rates during the 
nursery phase than in subsequent phases of the growout. Even if standard survival curves 
are used to estimate the population of a culture tank, adjustments will be necessary in cases 
where survival is unusually high or low. 
 
It is important to note that feeding tables only provide a guide to the amount the shrimp will 
eat under optimal conditions of temperature, density, water quality, etc. Following these 
feed tables religiously will invariably lead to overfeeding when conditions are sub-optimal. 
As an example, following a low dissolved oxygen condition, feeding activity is typically 
depressed. If the feed rates recommended by the feed tables are followed, much of the feed 
will go uneaten. The uneaten feed may even exacerbate the dissolved oxygen problem. 
High ammonia levels will also suppress shrimp appetites, and overfeeding will contribute to 
even higher levels ammonia in the tank. The feed table should serve only as a guideline for 
determining the daily feed allowance. 
 
 Chapter 7 – Nutrition and Feeding of Litopenaeus vannamei 
 - 135 - 
Demand-based Feeding 
Demand-based feeding is an alternative 
to using a feed table. With this method, 
the feed allowance is adjusted up or 
down depending on the feeding activity 
of the shrimp. At each feeding, the 
technician estimates the amount of feed 
that the shrimp can consume during the 
time interval between feedings. If a 
significant amount of feed remains 
from the previous feeding, the amount 
fed at the next feeding should be 
reduced by at least 10 percent. If all of 
the feed has been consumed between 
feedings, the feed amount can be 
increased by 10 percent. This approach 
to feeding ensures that the feed rates 
will be appropriate for the conditions in 
the tank. 
 
In clear water, it is easy to see how much of the feed is being eaten. However, if a dense 
algal bloom develops in a tank, it may be difficult to see uneaten feed on the bottom of the 
tank. One way to determine if the shrimp are eating all of the food is to place feed trays in 
the raceway. The trays can be lifted from the water to see if the feed has been eaten. 
Feeding Frequency 
The number of feedings per day is determined by pellet stability and by the rate at which 
the feed is consumed, digested and metabolized by the shrimp. Dividing the daily feed 
ration into multiple feedings, spaced several hours apart, improves feed conversion ratios 
and growth rates. In addition, feeding only what the shrimp can consume in 3 or 4 hours 
reduces losses of nutrients due to leaching. 
 
It is not clear whether or not there is any benefit derived from feeding the shrimp 
throughout the 24-hour period. While L. vannamei are active at night, they may not be 
actively feeding during this time period. Robertson et al. (1993) reported that L. vannamei 
receiving four feedings a day during daylight hours performed as well as, or better than, 
shrimp fed around the clock. 
 
Small shrimp metabolize their food faster than large shrimp, and generally require more 
feedings per day. Postlarval shrimp require frequent feedings because they have very high 
metabolic rates, but are not able to store much feed in their guts. Ideally, postlarvae should 
be fed every 2-3 hours. Longer intervals between feedings may result in heavy losses due 
 
 Figure 7-2: Weighing out shrimp feed 
 Chapter 7 – Nutrition and Feeding of Litopenaeus vannamei 
 - 136 - 
to cannibalism. Automatic feeders, which dispense small amounts of feed at programmed 
intervals or on a continuous basis, can be used to make sure the shrimp are fed in a timely 
manner. As the shrimp grow the feeding frequency can be decreased. Four feedings 
spaced three hours apart during daylight hours works well for juveniles larger than 1 gram 
in size. 
Feed Distribution 
Feed may be distributed to shrimp either by hand or by automatic feeders (Figure 7-3). 
The feeding method used is a function of the culture system, requirements of the culture 
organism and the preferences of the aquaculturist. 
 
Hand feeding is frequently practiced when feeding animals held in tanks or raceways, 
especially when the animals are small. Hand feeding allows the technician to modify the 
feed distribution in accordance with the feeding response. Hand feeding may be 
impractical when a large number of tanks must be fed because it is very time-consuming. 
 
Automatic feeders dispense a given 
volume of feed on a timed basis. 
Automatic feeders operate by a wide 
variety of mechanisms. Automatic feeders 
for larvae, fry, or small juveniles often 
consist of a plate or belt onto which feed is 
loaded (Figure 7-3). The plate or belt is 
rotated in a manner that causes feed to fall 
off into the water at a steady rate 
throughout the day. Scatter feeders 
distribute feed from a hopper suspended 
over the water at timed intervals. Scatter 
feeders have a plate at the bottom of the 
hopper with vanes extending radially from 
the center of the plate. At timed intervals, 
feed is released from the hopper and the 
plate spins around, casting feed in a 360° 
arc around the feeder. Scatter feeders can 
be modified for raceways to throw the feed 
out in a single 45-degree direction. Large-
scale operations with multiple raceways 
often use a conveyer system to load the 
hoppers. These consist of tubes through 
which feed is moved by a variety of 
means. Some use pneumatic blowers to 
move the feed, while others use augers or a 
similar mechanism. 
 
 
Figure 7-3: Automatic Belt Feeder 
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Feed Conversion Ratios 
An important measure of how well the feed is utilized by the animals in the culture system 
is the Feed Conversion Ratio or FCR. The Feed Conversion Ratio measures the number of 
pounds of feed required to produce a pound of shrimp. The following formula is used to 
calculate feed conversion: 
 
 
Feed Conversion Ratio = 
Total Weight of Feed Applied
TotalWeightGained
 (7.4) 
 
The lower the FCR value, the more efficiently the feed is being utilized. Generally 
speaking, FCR values less than 2.0 are considered good. High FCR values may result from 
nutritionally deficient feeds, overfeeding, poor water quality or crowding. Whenever high 
FCR values are obtained, it is important to take a critical look at the feeding program and 
production process to try to identify the causes. 
Feed Storage 
Feed storage is an important and often neglected aspect of the feed management program. 
Aquaculture feeds are highly perishable. Inadequate storing and handling of feed can lead 
to nutrient losses, rancidity, mold growth and rodent infestations. 
 
Many of the vitamins in the feed are unstable at high temperatures and significant losses 
will occur if the feed is stored at high temperatures or exposed to ultraviolet light. Vitamin 
C (ascorbic acid) is particularly prone to degradation. At room temperatures, ascorbic acid 
has a half-life of less than a month. Two-month old feed will have a small fraction of the 
amount of ascorbic acid that was originally added to the feed. StabilizedVitamin C (Stay 
C) is much more stable, but still is degraded over time. 
 
Feeds that are high in lipids often will become rancid when stored in warm, oxidative 
environments. Rancid feeds are unpalatable to the shrimp and are deficient in Vitamin E. 
Reduced growth rates are commonly seen in shrimp receiving rancid feeds. Rancid feeds 
have a very distinctive odor. The technicians should be sure to smell a handful of feed 
from each feed sack that is opened before using the feed to determine if the feed has gone 
rancid. 
 
Molds will often develop on feeds that are stored in humid or moist environments. Molds 
produce toxins that can be very damaging to the shrimp. Molds of certain species in the 
genus Aspergillus produce aflatoxins, which can cause severe liver damage to the shrimp. 
Given the correct environment, molds grow quickly on the feed. Feed does not have to be 
old to be moldy. Occasionally feed will already have mold growing on it when it arrives 
from the feed mill. This can happen when the feed is placed into the feed bag while it is 
still hot, or if the feed not been dried sufficiently. When hot feed cools, moisture condenses 
on the feed. The dark, humid environment inside the feed sac is a perfect incubator for 
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mold growth. When receiving feed, inspect a few bags to make sure that the no mold is 
present. If mold is detected, the shipment should be rejected. Before using the feed from 
any feed bag, inspect the feed for mold. If even a small amount of feed in a bag appears to 
be moldy, discard the entire bag. Significant quantities of mold toxins will be present 
throughout the bag. 
 
Unless the feed is stored in a sealed room with narrow clearances around the door jam, the 
feed will soon be infested with rodents. Besides eating the feed, rodents will urinate and 
defecate in the feed sacks, ruining the feed. 
 
To avoid the kinds of problems described above, feed should be stored in a dry, cool, 
rodent-resistant storage shed. If possible the feed storage room should be air-conditioned. 
The air conditioner will help maintain a low humidity, as well as a cool storage 
environment. A “first-in, first-out” inventory management strategy should be employed to 
make sure that feed gets used before its expiration date. Ideally, feed should be used within 
one month of purchase. If storage conditions are ideal, feed can be used for up to three 
months, although the quality of the older feed will not match that of feed less than one 
month old. 
Sources of Shrimp Feeds 
The following is a list of U.S. shrimp feed manufacturers: 
 
Bonney, Laramore, and Hopkins, Inc. 
5600 Highway U.S. 1 North 
Ft. Pierce, FL 34946 
Tel: (561) 971-2925 
 
Burris Mill and Feed , Inc. 
1012 Pearl Street 
Franklinton, LA 70438 
Tel. (504) 839-3400 
Fax: (504) 839-3404 
 
Cargill Nutrena Feeds 
801 South Poplar Street 
Florence, AL 35630 
Tel. (205) 764-1331 
 
Ralston Purina International 
Checkerboard Square –11T 
St. Louis, MO 63164 
Tel. (314) 982-2402 
Fax. (314) 982-1613 
Rangen Feeds 
115 13th Ave. S. 
Buhl, ID 83316 
Tel. (800) 657-6446 
Fax (208) 543-4698 
 
Rangen Feeds 
Angleton, TX 
Tel. (979) 849-6757 
 
Star Milling Company 
PO Box 728 
Perris, CA 92370 
Tel. (909) 657-3143 
Fax (909) 943-2400 
 
Zeigler Brothers, Inc. 
PO Box 95 
Gardners, PA 17324-0095 
Tel. (800) 424-2033 
Fax (717) 677-6826 
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Literature Cited 
 
Akiyama, D. M., W.G. Dominy, and A.L. Lawrence. 1991. Penaeid shrimp nutrition for the 
commercial feed industry: Revised. Pages 80-98 in D.M. Akiyama and R.K.H. Tan, 
editors. Proceedings of the Aquaculture and Feed Processing and Nutrition 
Workshop. Singapore, Republic of Singapore. 
 
Davis, D.A. 1990. Dietary mineral requirements of Penaeus vannamei: evaluation of the 
essentiality for thirteen minerals and the requirements for calcium, phosphorus, 
copper, iron, zinc, and selenium. Ph.D. Dissertation, Texas A&M University, 
College Station, TX, USA. 
 
Davis, D.A. and D.M. Gatlin III. 1991. Dietary mineral requirements of fish and shrimp. 
Pages 49-67 in D.M. Akiyama and R.K.H. Tan, editors. Proceedings of the 
Aquaculture and Feed Processing and Nutrition Workshop. Singapore, Republic of 
Singapore. 
 
Kanazawa, A., and S. Teshima. 1981. Essential amino acids of the prawn. Bul. Jap. Soc. 
Sci. Fish. 43(9): 1111-1114. 
 
Lim, C. and A. Persyn. 1989. Practical Feeding – Penaeid Shrimps. In, Editor, Tom 
Lovell. Nutrition and Feeding of Fish. Van Nostrand Reinhold. New York. pp. 205-
222. 
 
Robertson, L., A.L. Lawrence, and F.L. Castille. 1993. Effect of feeding frequency and 
feeding time on growth of Penaeus vannamei (Boone). Aquaculture and Fisheries 
Management 24: 1-6. 
 
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