this talks about the nutritional factors that are associated with the spawning, maturation growth and reproduction of fishes. and the recently advanced feeds

1. Prepared By- Joynal Abedin
Dept. of Aquaculture
A PRESENTATION ON:
Nutritional Factor Related to Maturation,
Spawning, and Rearing

2. Essential Fatty Acids
 Membrane constituents and energy reserves in embryos
 Dietary requirement of linolenic and linoleic acid is of 1% each
and EPA & DHA is 0.5%

3. PROTEIN

4. CONT..
 Reduction of dietary protein incorporation from 51% to 34% together
with an increase in dietary carbohydrate levels from 10% to 32%
reportedly reduced egg viability in seabass (Cerda, et al., 1994).
 Such alteration in diets have been shown to influence GnRH release
during spawning (Kah et al., 1994).
 Ultimately alters plasma gonadotropin GtH II levels, that latter
known to play an important role in oocyte maturation and ovulation
(Navas et al., 1996).
 Balanced dietary protein promotes ‘Vg’ synthesis, which lead to high
fecundity and egg quality.

5. Carbohydrate
 For example,
omnivorous/herbivorous
freshwater fish can metabolize
high quantities of CHO in diets
whereas carnivorous species
use it less efficiently.
 Overall, fish do not appear to
have a specific dietary
requirement for carbohydrates.
Some
carbohydrate
is deposited
in the form of
glycogen in
tissues such
as liver and
muscle
Some dietary
carbohydrate
is converted
to lipid and
deposited in
the body for
energy.

6. Vitamins
 Fishes (carps) lacks the enzyme gulono lactone oxidase needed for
conversion of glucose into Vitamin C (mukhopadyay et.al, 1996)
 It involves in the biosynthesis process of gonadal steroid hormones.
Participates in collagen biosynthesis particularly in connective tissues.

7.  Fishes can absorb minerals directly form water itself.
 Phosphorus is a major constituent of hard tissues such as bone
and scales and is also present in various biochemical processes.
Impaired growth and feed efficiency, as well as reduced tissue
mineralization and impaired skeletal formation in juvenile fish,
are common symptoms when fish have diets deficient in
phosphorus.
Minerals
Micro
• Required in smaller amounts in the diet
• Eg. Sodium, chloride, potassium and phosphorous
Macro
• Required in large amounts as components in enzyme and
hormone systems
• Copper,iron, chromium, iodine, zinc and selenium
Fig. Mineral deficiency
in juvenile fishes

8. Probiotics
 Probiotics are live microorganisms that when ingested in adequate
amounts, exert a health benefit on the host.
 These effects might be mediated by changes in expression of genes
such those encoding GnRH, leptin and vitellogenin (vg).
Zebra
Fish
Gonad
Fecundity
Bone
Maturation
Viability
Hatching

9. Brood Nutrition
 Feeds based on soybean meal, rice bran or wheat bran and oilcakes in equal
proportions at 3-5% of body weight per day benefit their gonadal development.
in the ratios of 4:4:1 :1. Mustard oilcake, if used, should be presoaked (for
softening) in water overnight.
 Production of zooplankton at 30-50 ml per 1,000 liters of water are very
important, for Catla
Soyabean
Meal
Rice
Bran
Oil Cake

10. It advances gonad growth and maturation, facilitates
early spawning and significantly increases spawning
efficiency
It is most suitable for off-season gonad
recrudescence which ultimately ensures
multiple/repeated breeding in carp.
The rate of feeding is suggested to be in the range of 3-
5% of total body weight during vitellogenic phase of
ovarian development
CONT.

11. Microencapsulated diet
Disease Control
Agents
Quality
Enhancer
Heigh Quality
Nutrition
Encapsulant
Surfactant
Tailored size, shape,
Surface texture
and, buoyancy
Source: D.F. Willer and D.C. Aldridge

12. • It can be seen that it consists of aggregates
of tiny spherical droplets of fat encased in
heat coagulated protein capsules.
• This thin coating is insufficient to protect the
lipid from oxidation by the atmosphere thus
leading to rapid onset of rancidity and mould
formation on the exposed product.
• This emulsion consists of countless
microscopic-sized fat droplets (yolk)
dispersed in the same immiscible watery
medium
• Coagulation of the dispersing medium
will permanently coat the tiny lipid spheres
to produce a microencapsulated whole egg
product.
Unhomogenized
Whole eggs
Homogenized
Whole eggs
Micro-encapsulated whole egg

13. Flake
• Flakes can be reduced to smaller
particle sizes without reducing the
basic stability characteristics.
• Vegetable binders can be used to
achieve the water stability needed to
optimize residence time of the flake
in the aqueous system.
•.
•Destroys harmful organisms such as
salmonella, and deactivate enzymes
responsible for rancidity
•Starch is gelatinized and oil cells are
ruptured
•Neutralizes growth inhibitors.
•Improves palatability
Extrude

14. THANK YOU !
“For Your Patience Listening”