Feed formulation is the major part of aquaculture.The main objective of feed formulation is to utilize the knowledge of nutrient requirements, locally available feed ingredients and digestive capacity of fish for the development of a nutritionally balanced mixture of feed stuff…
2. INTRODUCTION
• Demands for domestic fish for food and recreational value
increased…
• AQUACULTURE practices are intensive or semi intensive..
• So external feeds are required..
• Such feeds are one of the major recurring coast of fish farming..
• Proper nutrition is one of the most important factors influencing
the ability of cultured organism in sexual maturity, growth and
longitivity..
• The nutrients requirement varies with species, within species also
varies with different life stages…
• The main objective of feed formulation is to utilize the knowledge
of nutrient requirements, locally available feed ingredients and
digestive capacity of fish for the development of a nutritionally
balanced mixture of feed stuff…
3. FORMES OF DIETS
• Diets supplied to aquatic organisms could vary in form
• Possible feeds include
• Live foods ; generally required for the culture of most aquatic
organisms in their larval stage..
• Forage materials; like grasses, or macrophytes, which may be
introduced into the culture system or made to grow in the culture
system.
• Prepared foods; including a wide array of feeds, ranging from
simple , on farm based mixtures of a few ingredients to
microencapsulated diets..
• Most widely used are the third type…
4. FEED INGREDIENTS
• Animal and fish feed ingredients are for the most part by products from the
human food processing industry ..
• Feed ingredients are produced following the extraction of high value food
from raw materials which are considered unsuitable for human consumption.
• A wide variety of ingredients are available for use in fish and crustacean
feeds, they are
1. Grasses
2. Legumes
3. Miscellaneous fodder pants
4. Fruits and vegetables
5. Root crops
6. Cereals
7. Oil-bearing seed and oil cakes
8. Animal products
9. Miscellaneous feed stuffs
10. additives
5. 1. Grasses
Grasses are normally utilized either fresh or in the form of hay or silage.
Grasses are added very limited in fish foods. Dried grass used in shrimp
feeds as a source of carotenoids. Grasses are of limited value in fish
feeds except for herbivorous fish.
2. Legumes
The leaves and stems of legumes are not much use in aquaculture, except
the plants like alfalfa, ipil-ipil etc...
Legumes are rich in protein (20-50%) and minerals. Leguminous seeds
are rich in lysine but poor in methionine..
Eg: acacia, clover, lucerne, ground nut(peanut) gram, lentil, locust beans,
chickpea, guar, ipil-ipil, beans, field peas, mug peas, soya beans etc...
3. Miscellaneous fodder plants
The leaves and other areal part of many plants, other than those
specifically grown for fodder are classified as miscellaneous fodder.
These parts are washed and dried and used as leaf meal. These feeds
have an advantage that it can not deteriorate the water quality.
6. 4. Root crops
Root crops , with some exceptions , are very deficient in protein,
calcium, phosphorous and vitamins. Waste from root crops can be
utilised in small quantities in compound feeds, but generally many
required heat treatment to destroy the toxins they contain. Some root
crops have an extra important in aquaculture that is , they give stability
to feed in water. So they use as binders...
Eg: potato, cassava, yams, carrots
3. Cereals
cereals and cereal by products , despite their high carbohydrate content
form an important component in fish feeds .they act as a good binder.
Cereals also rich in protein and lipid content of diet . Though deficient in
some amino acid (eg: lysine) . They can be used to balance high animal
and vegetable protein content .
4. Oil bearing seed by-products
Many plants are farmed specifically for oil extraction, and a vast
quantity of by products are coming from the vegetable oil industry.
These are used widely in animal feed production like aquaculture.
7. They are high in protein and low in protein , so potential content for
aquaculture feed formulation.
Eg: soya bean, groundnut, mustard, sunflower, palm, coconut,
sesame, poppy, cotton etc...
7. Animal by products
Animal by products are either terrestrial, avian or marine animal
origin. They constitute the most important and most expensive
ingredients of aquaculture feeds . These feed stuffs are necessary
to balance the amino acids and vitamin deficiency in cereals and
other plant part products in complete diet.
Fish meal is the major animal by- product used in aquaculture, also
blood meal, feather meal, poultry meal, meat, raw fish, fish oils,
fish silage, shrimp meal, and meat by products
By far the most suitable animal products for incorporation with fish
diet are fish meal. It is mainly marine fishes such as by catches or
a product of specific fishery such as Peruvian anchovy fisheries.
8. Traditionally in Asian countries like India and China animal by
products such as silkworm pupae have been –and are being used
as a feed for fishes.
8. Miscellaneous feed stuffs
Many ingredients have potential use in aquaculture feeds, however
their value has not yet been fully assessed. Some of these
ingredients are conventional or non conventional. The
conventional . These are include the sugarcane molasses, leaf
protein concentrate, minerals , sea weeds etc...
9. Additives
An increasing diversity of additives is being used in animal feed
stuffs, including synthetic amino acids, vitamins, binders, anti
oxidants, preservatives, prophylactic medicines, hormones, and
growth promoters etc... Most of these have very specific uses and
may be non-nutritive.
9. DIET FORMULATION
• Diet formulation is a process in which the appropriate feed ingredients
are selected and blended to produce a diet with the required quantities of
essential nutrients .
• No single ingredient can be expected to meet all the nutrient
requirement of a cultured organism.
• Various ingredients which is nutritionally balanced , pellatable,
palatable and easy to store are used to formulating feeds.
• The basic information required for feed formulation are:
1. Nutrient requirement of the species cultivated
2. The feeding habit of the species
3. Local availability, cost and nutrient composition of ingredients.
4. Ability of the cultured organism to utilise nutrients from various
ingredients as well as the prepared diet.
5. Expected feed consumption
6. Feed additives needed
7. Type of feed processing desired
10. • Man factors to be considered when formulating feeds for use in
aquaculture .
• Feed cost is considered to be the highest operational cost in both
intensive and semi intensive aquaculture systems.
• Supplying adequate nutrition for various aquaculture species involves
the formulation of diets containing about 40 essential nutrients and
proper management of multitude of factors relating to diet quality and
intake.
• So it is ensure that feed formulae developed are nutritionally and
economically sound.
• An economic diet is expected to produce a kilogram of healthy fish at
the least cost under normal growing conditions.
• To formulating economically sound and nutritionally balanced diets we
can use two mathematical calculations.
• The are Pearson squares and linear programming.
• On the basis these formulae man computer programmes are developed
for feed formulation.
11. Pearson squares
• Formulation of diets with a few ingredients ,and in which amino
and fatty acid balances are not taken into consideration.
• It is one of the best and simply achieved method
• The complicated least cost formulae used in Pearson squares are
based on series of simultaneous equations.
• It can be balanced only one nutrient (make your choice for crude
protein or crude fat)
Sample Calculation
1. Please calculate to prepare a fish feed that includes 45% crude
protein, using fish meal and corn gluten meal…
2. Always keep in mind the nutrient value of
the ingredients…
3. Fish meal includes 65% crude protein,
4. Corn gluten meal includes 40% crude protein…
12. 5. What will be the solution to reach 45% crude protein using fish
meal and corn gluten meal?
6. The solution is to create a mixture rip…
Fish meal, 65% 5
45%
Corn gluten meal, 40% 20
⁺------
25
% of Fish meal is calculated as: (5 x 100) / 25 = 20
% of Corn gluten meal is calculated as: (20 x 100) /25 = 80
7. The contribution from fish meal is: 20% x 65 = 13
The contribution from corn gluten meal is: 80% x 40 = 32
The total is: 13 + 32 = 45
If we have more than two ingredients take them as groups and
calculate the average value of each group.
13. Linear programming
• Another mathematical technique available to nutritionists for selecting the
best combination of feed ingredients to formulate diets at the least possible
cost is linear programming.
• The information necessary for using the technique includes
1. Protein and fat content in the diet
2. Nutrient content and DE(digested energy) or ME (metabolisable energy)
of ingredients
3. Unit price of feedstuffs including vitamin and mineral mixture.
4. Any other additives to be considered to be used in the feed
5. Minimum and maximum restriction on the amount of each ingredient in the
feed.
Least cost linear programming software's for feed formulation are readily
available, the price varies with sophistication required.
A commonly used spreadsheet such as Lotus 1-2-3 can also be used for feed
formulation.
It is a high coast methode so not useful for local farmers.
14. Factors to be considered in feed formulation
As mentioned previously , many factors need to be considered in
order to formulate a feed which will provide optimal growth
performance of the cultural organism,
These factors are
1. Nutrient requirement
It is of vital importance that a formulated feed meet the nutritional
requirement of cultural organism. It mainly depends the intensity
of the culture. The feed may be expected to provide all of the
nutritional required or only some of it.
In order to do this , it has been suggested that the species, strain,
stage of development and health, as well as temperature and
environmental conditions of the culture systems be taken into
account. All these factors have been shown to affect the nutritional
requirements of the fish.
15. 2. Composition of ingredients
A knowledge of the nutrient composition and available energy of
dietary ingredients is essential for their selection for used in diet
formulation.
The compositions of feed stuffs are known to vary regionally,
seasonally, and also with soil fertility and type of processing and
storage .There for, it is desirable that each batch of feed
ingredients is analyzed for actual contents.
3. Digestibility and nutrient availability
If feed formulation is performed correctly, a knowledge of
digestibility of the individual nutrients of all the ingredients is
essential. The process of estimating these is tedious and time
consuming. However general digestibility values for most of the
major ingredients for the widely culture species are presently
available and are often used in feed formulation.
16. 4. Other dietary components
Certain ingredients are added to the diets for physiological or
economic reasons, and include binders, antioxidants etc…
These are added in small quantities and often have no direct
nutritional value and do not act as energy sources.
However , when formulating feeds , allowances need to be made for
their inclusion.
5. Flavour quality
The influence of environmental factors on the organoleptic
properties of marine fish has been known for sometime. These
factors include not only dissolved substances, the composition of
the food chain, but also physical factors such as temperature,
photoperiod and water cycle. At lower temperature, fish tend to
accumulate more unsaturated fatty acids in their tissues. As the
fatty acid composition is related to flavour and texture of fish
meat. so uniform environmental maintenance also an important
factor in feed formulation.
17. CONCLUSION
• Feeding is the major factor which determines the economic gain
from aquaculture. It is also the major cost in aquaculture
practices. So the feed formulation is a significant one.
• The feed we given to fish must contain energy sources, minerals,
vitamins, other major and minor elements etc..
• The correct proportion of the metabolites with lesser cost is the
basic of feed formulation
• The ingredients used for feed preparation are grasses, legumes,
cereals, fruits and miscellaneous parts of plants, animal products
etc..
• There are two mathematical methods are used for this, the are;
Pearson square method and linear programming method.
• Also along with nutritional components in feeds , the
environmental factors, digestibility, feeding habit , expected feed
consumption etc… are also important