Tilapia: Taxonomy, Biology and Reproduction, Feeding

behavior and Environmental requirements

Jitendra KumarDFK 1303

Dept of FRM

TAXONOMIC CLASSIFICATION

Phylum: ChordataSubphylum:

VertebrataClass:

OsteichthyesOrder: PerciformesFamily: Cichlidae

“Tilapia” is the generic name of a group of cichlids endemic to Africa.

Introduction

Tilapia is one of the most widely cultured fish in the world.

Currently, farmed tilapia represents more than 75% of world tilapia production (FAO, 2009),

Several factors have contributed to the rapid global growth of tilapia.

Tilapia are easily cultured and highly adaptable to a wide range of environmental conditions.

Genus Tilapia: Includes those species which are substrate spawners and do not keep the eggs in the mouth for incubation

Genus Sarotherodon: Includes those species which are mostly paternal mouth brooders and sometimes eggs and hatched larvae.

Genus Oreochromis: Includes those species which are exclusively maternal mouth brooders. In this group the males construct and defend a mating territory in an arena with other males in adjacent terrirories, and females come to find spawning partners, e.g. O. niloticus, O. aureus, O. mossambicus.

A total of about 70 species of tilapia have been so far listed as native to Africa.

Only a few species are suitable and popular for farming in ponds and other culture systems, which include-:

Nile tilapia(Oreochromis niloticus)Mozambique tilapia (O. mossambicus)Blue tilapia (O. aureus)three spotted tilapia (O. andersonii) etc..

There are also some genetically improved strains such as Genetically Improved Farmed Tilapia (GIFT), red tilapia strains and hybrids.

Mozambique tilapia, Oreochromis mossambicus

Oreochromis mossambicus is native to Malawi, Mozambique, Swaziland, Zambia, Zimbabwe and South Africa.

Oreochromis mossambicus is a popular fish among fish farmers since it is hardy and easy to grow.

The fish is a popular food fish with white, mild flesh. It is however far from the most common tilapia species in aquacultures;

roughly 4 percent of the total global tilapia aquaculture production is made up by Oreochromis mossambicus.

Mozambique Tilapia in Aquacultures

Mozambique tilapia can be kept in aquariums but only if you have a big aquarium since it can exceed 40 cm (16 inches) in length as an adult.

It grows really fast, so you will need that large aquarium fairly soon even if you purchase small juvenile specimens.

The Mozambique tilapia is a hardy species,

Mozambique Tilapia in Aquariums

Conservation Status for Oreochromis Mossambicus

The Mozambique tilapia, Oreochromis mossambicus, is listed as Near Threatened (NT) on the IUCN Red List of Threatened Species.

This is a problem, since this two species readily mates with each other which leads to hybridization.

According to IUCN, the Mozambique tilapia is likely to become locally extinct in those systems.

Hybridization is not the only problem; competition can also pose a threat to the Mozambique tilapia.

Nile tilapia, Oreochromis niloticus

Morphology

Caudal fin with regular dark vertical stripesDorsal fin with dark marginRed coloration on head and lower part of

the body in breeding malesVariable coloration in females dependent

on subspecies- some may show coloration similar to males during breeding season

BehaviourDuring the day fish may form large

schools that break up during the night and reform at dawn

DietJuveniles

Diurnal feeding patternOmnivorous as fry consuming primarily copepods, and insectsBy 6 cm TL, diet becomes primarily phytoplankton

AdultsDiurnal feeding patternPrimarily utilize phytoplankton (blue-green algae and diatoms) but may also consume macrophyteswhen phytoplankton densities are low

Life CycleMaximum size of 64 mm TLTypically obtain a total length of 25

cm by second year

Maturityfirst sexual maturity 9 to 15 cm TL

Age at maturity occurs in first year between 5 and 10 months of age

Habitat CharacteristicsPrefers temperatures between 28 –

30 deg C depending on acclimation temperature

Can tolerate low dissolved oxygen (0.1ppm)

Genetically Improved Farmed Tilapia (GIFT) strain.

In Bangladesh, comparative growth and production potential of GIFT and existing Nile tilapia strains (O. niloticus) was evaluated both under on-station and on-farm conditions.

Total yield of the GIFT was significantly higher (57% more; P<0.05) than that of the existing strain.

GIFT strain for aquaculture

High yieldingExcellent breederEfficient converter of organic and

agricultural wastes in to high quality proteinResistant to diseaseVery hardyTolerant to over crowding conditionsAble to grow in either fresh or brackish

water

Nile tilapia is an important food fish that has been introduced to many different parts of the world by man.

It can today be found on all continents except Antarctica.

In several countries, Nile tilapia has become a problematic invasive species after its introduction.

Tolerance to ecological conditionsWater temperatures 12 to 35oCpH 6.5 – 8.0Dissolve oxygen 2.0 – 8.0 mg/lSalinity 3 - 25 ppt

Growth

Nile tilapia can grow to 150 – 250 g in 4 to 6 months, 500 to 800 g in 10 to 12 months and 2 – 3 kg in 2 years.

Food

O. niloticus is capable of using a wide range of food materials from tiny plankton (phytoplanton and zooplankton) to macrophytes.

It grows well on artificial feeds.

Fecundity

Colour of ripe and fertilized eggs is pale yellow orange

size ranges between 1.0-2.0 mm x 1.5-3.0 mm in diameter,

and 2.3 – 2.8 mm in length

The fecundity fluctuates widely from a few hundred to several thousand eggs, depending on the size and age of the female.

O. niloticus embryonic development there are five easily observed developmental stages (Hussain 1992)

• Morula stage: 6-8 hrs. after fertilization (a.f.)

• Pigmentation stage: 45-50 hrs. a.f.

• Hatching stage: 70-90 hrs. a.f.

• Yolk sac resorption stage: 6-10 days a.f.

• First feeding stage: 12 – 14 days a.f.

Production and Economics for Culture of Tilapia in

Semi-intensive System

(Area of Pond :1 Ha Duration : 7-8 months)

Sr. No.

particulars Rate of Appli.(/ha)

Unit price(Rs.

)

Quantity (1ha)

Amount (Rs)

1 Dewatering of pond (Diesel) 40 lit. 50/- 40 lit. 2000/-2 Drying of pond - - - -3 Ploughing of pond (Tractor) - 300/-per

hr.8 hr. 2400/-

4 Lime application 300 kg 5/- 300 1500/-5 Fertilizer(Organic) 5000kg o.5/- 4 ton 2000/-6 Fertilizer( Urea) 25 kg 5/- 25 kg 125/-7 Fertilizer (SSP) 75 kg 5/- 75 kg 375/-8 Fertilizer (GOC) 200 kg 20/- 200 kg 4000/-9 Seed (Fingerling) 2/m2 0.5 20,000 10,000/-10 Feed (GOC + RB) /A.F.(25-32%

protein)2-3% 18/-/Kg 7000kg 1,26,ooo/

-11 Miscellaneous Expenditure - - - 5,000/-12 FCR - - 2.0 -13 Average Growth - - 220 (g) -14 Survival - - 80% -15 Production - - 3500 Kg -16 Sale Price (Rs./kg) - - - Rs 80/kg17 Total Income (Rs) - - - 2,81,600

/-18 Total Expenditure - - - 1,53,400/

-19 Net Income (Rs) (17 – 18) - - - 1,28,200

/-

Production and Economics for Culture of Tilapia in Semi-intensive System

Conclusions

Tilapia are a good fish for warm water aquaculture.

They are easily spawned, use a wide variety of natural foods as well as artificial feeds, tolerate poor water quality, and grow rapidly at warm temperatures.

These attributes, along with relatively low input costs, have made tilapia the most widely cultured freshwater fish in tropical and subtropical countries.

Consumers like tilapia’s firm flesh and mild flavor, so markets have expanded rapidly in U.S. during the last 10 years, mostly based on foreign imports.

Thank You