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CHAPTER I

GENERAL INTRODUCTION

1.1 Background

Cyprinus carpio Linnaeus (1758) is one of the commercially important and oldest

domesticated freshwater fish in the world. Cyprinus carpio is more popularly known as

the common carp, German carp, or European carp. It belongs to the order Cypriniformes

and the family Cyprinidae. The family Cyprinidae (cyprinids) is one of the largest

families of freshwater teleost fish having seven subfamilies, 220 genera and

approximately 20,000 described species (Howes, 1991). The native range of common

carp extends from Japan (Mabuchi et al., 2005) to the River Danube in Eastern Europe

(Balon, 1995a). Human activities associated with the cultivation and domestication of

carp for food and for ornamental characteristics, however, have introduced common

carp into many new waterways throughout Asia, Africa, the Americas, Oceania,

Australia and New Zealand (Koehn et al., 2004). Now the species comprises different

genetic variants in different parts of the world (Chistiakov and Voronova, 2009).

In India the C. carpio communis (Chinese stock) popularly called scale carp that

was introduced in 1957 is found in all over country (Reddy, 2005). In has been

hypothesized that certain micro-mutations may or have created changes in their genetic

constitution. The molecular markers have immense help in finding out the differences in

the species and to determine genetic distance between individuals or populations. In the

current study an attempt has been made to evaluate the genetic variability of common

carp in India and differences of proximate compositions among the genetic variants if

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any. This will help in the understanding of the genetic variability and proximate

biochemical compositions of exotic fish species Cyprinus carpio in India and Northeast

India in particular.

1.2 Taxonomy of Cyprinus carpio

Linnaeus first described Cyprinus carpio in 1758. Cyprinus carpio is

taxonomically a confusing species. According to the review by Barus et al., (2002) it

remains without a holotype and was described ‘using specimens from pond culture,

designating Europe as the terra typica. Presuming that all domestic European forms

originated as wild carps from the Danube, specimens from the Danube River can be

considered as typical’. Most of the confusion comes from giving quasi taxonomic

names to feral specimens or populations. For example, Zhou & Chu (1986) list 12

species from Yunan Province, China, and Barus et al., (2002) cite more than 30

synonyms and over 10 sub-species, varieties and morphs from across its range. This

compares with those given by Kottelat (1997) of 15 sub-species and eight varieties and

morphs. Using the best data available, Barus et al., (2002) concluded that only three

sub-species of Cyprinus carpio can be recognized which are the European and central

Asian common wild carp, Cyprinus carpio carpio L., the East Asian common wild carp,

Cyprinus carpio haematopterus Temminck & Schlegel, 1846 and the south-east Asian

wild carp, C. carpio viridiviolaceus Lacepe de. None of the data are convincing, nor is

the claimed occurrence of Cyprinus carpio haematopterus throughout East Asia from

the Amur River across China, Korea and Japan. More than 200 years earlier, the first

colonies of the Portuguese and the Dutch were established at Nagasaki. Common carp

culture was by then widespread in the European homelands of these colonists and it is,

therefore, possible that the common carp was introduced by them to Japan (Balon,

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1995b, 2004). Tableware decorated with common carp images once belonging to these

early Dutch colonists can be seen on display in a Nagasaki Museum (Balon, 1995b).

While Cyprinus carpio haematopterus became the nominal sub-species for China, it is

possible that these were feral descendants of domesticated European fish that escaped or

were introduced in Japan and possibly China. This taxonomic confusion may be

resolved by molecular markers but it would be more prudent to consider the wild

ancestor of the common carp as a single species, Cyprinus carpio, widely distributed

from the Danube to the Amur river, as feral forms elsewhere and as naturalized

wherever suitable conditions prevail (Lever, 1996). Common carp are closely related to

goldfish. The two are often confused, and the two species are mainly distinguished by

the presence of two pairs of barbels on either side of the common carp’s mouth (Curtin,

2001).

Figure 1.1. Morphology of Common carp (adapted from Haynes, 2009)

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Figure 1.2. Wild common carp (a) and its feral form (b) from Danube delta in 1990

(from Antipa, 1909; Balon, 2004)

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Figure 1.3. Photographs of Cyprinus carpio communis found in India

Systematic Position of Cyprinus carpio

Domain: Eukaryota - Whittaker & Margulis,1978 - eukaryotes

Kingdom: Animalia - Linnaeus, 1758 - animals

Subkingdom: Bilateria - (Hatschek, 1888) Cavalier-Smith, 1983

Branch: Deuterostomia - Grobben, 1908

Infrakingdom: Chordonia - (Haeckel, 1874) Cavalier-Smith, 1998

Phylum: Chordata - Bateson, 1885 - Chordates

Subphylum: Vertebrata - Cuvier, 1812 - Vertebrates

Infraphylum: Gnathostomata - Auct. - Jawed Vertebrates

Superclass: Osteichthyes - Huxley, 1880 - Bony Fishes

Class: Osteichthyes - Huxley, 1880 - Bony Fishes

Subclass: Actinopterygii - Ray-Finned Fishes

Infraclass: Actinopteri

Cohort: Clupeocephala

Order: Cypriniformes

Family: Cyprinidae - Minnows and Carps

Subfamily: Cyprininae

Genus: Cyprinus - Linnaeus, 1758

Specific name: C. carpio - Linnaeus, 1758

Scientific name: Cyprinus carpio Linnaeus, 1758

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1.3 Habitat and biology of Cyprinus carpio

The Cyprinus carpio is an adaptable freshwater species. The species is typically

full-scaled and coloured silvery-black or grey, olive-green or yellow-brownish on their

backs, softening to pale yellow or cream on their bellies (Figure 1.1) (Kirpitchnikov,

1967; Balon 1995a; Lintermans, 2007), although many colour and scale variants occur

in both wild and cultivated populations. They are globally distributed and has firmly

established populations on every continent except Antarctica (Lever, 1996). Common

carps are tolerant to low oxygen levels, high levels of turbidity, moderate salinity

(14%), a wide range of temperatures (2 - 40.6 °C) and high levels of toxicants (Koehn

2004). Wild common carp live in the middle and lower streams of rivers, in inundated

areas, and in shallow confined waters, such as lakes, oxbow lakes, and water reservoirs.

Common carp are mainly bottom dwellers but search for food in the middle and upper

layers of the water body. They sucked sediments into their mouths and expelling

indigestible particles through their gill openings (Billard, 1999; Koehn et al., 2000).

Best growth is obtained when water temperature ranges between 23 °C and 30 °C.

Common carps can reach 0.6 to 1.0 kg body weight within one season in the

polycultural fish ponds of subtropical/tropical areas. Growth is much slower in the

temperate zone: here the fish reach the 1 to 2 kg body weight after 2 to 4 rearing

seasons. The maturity period of Asian carp strains is slightly shorter. The spawning of

European carp starts when the water temperature is 17-18 °C. Asian strains start to

spawn when the ion concentration of the water decreases abruptly at the beginning of

the rainy season (Crivelli, 1981). In tropical and subtropical regions carp usually mature

during their first year and may spawn several times within a given year (Sivakumaran et

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al., 2003). Female gonad development is continuous when temperatures are above 16°C

(Crivelli, 1981). Wild common carps are partial spawners (Tekelioglu, 2000).

Domesticated common carps release all their matured eggs within a few hours.

Common carp is capable of laying eggs in the closed fish rearing ponds (Bauer and

Schlott, 2004).

1.4 Food and Feeding of Cyprinus carpio

Common carp are bottom feeders, feed by filtering small particles from the water

or by sieving food items from the bottom sediments, sucking sediments into their

mouths and expelling indigestible particles through their gill openings (Koehn et al.,

2000). During feeding, food is sucked into the mouth along with water and sediments.

At the entrance to the pharynx or throat, gill rakers form a meshed structure that can

sieve out larger items from the ingested water and sediments, which are expelled

through the opercular openings behind the gills. This behaviour can stir up fine

sediments and increase turbidity (Koehn, 2004). Their diet varies, depending on what

foods are available, but they are known to eat micro crustaceans, aquatic insect larvae,

molluscs, swimming and terrestrial insects and seeds and other plant matter (Koehn et

al., 2000). According to Eder and Carlson (1977), they are omnivorous, feeding mostly

on benthic organisms (e.g., chironomid larvae and pupae), detritus, and algae. Juvenile

carp feed mainly on small planktonic animals, smaller crustaceans and insect larvae. As

common carp grow they gradually eat larger crustaceans and aquatic insects, along with

some plant material. Common carp have a high tendency towards the consumption of

animal food, such as water insects, larvae of insects, worms, molluscs, and zooplankton.

Zooplankton consumption is dominant in fish ponds where the stocking density is high.

Additionally, the common carp consumes the stalks, leaves and seeds of aquatic and

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terrestrial plants, decayed aquatic plants, etc (Flajshans and Hulata, 2006). They are

voracious feeders. With the extendible mouth they suck in all the decaying materials

and the micro organisms along with the clay from the bottom of the pond and take in the

feed and expel the clay and other non edible portions. They also eat up all kinds of

micro organisms, worms and small aquatic creatures found at the bottom of the pond.

They have the habit of making holes on the sides and at the bottom of the pond and

thereby affect the stability of the pond or the trees that may be growing on the bank of

the pond (Zambrano and Hinojosa, 1999). Their diet may alter depending on prey

densities (Scheffer, 1998). For example, high density, cyprinid populations like Green

Lake common carp may switch to feeding on zooplankton when abundant rather than

benthos. High predation pressure on algae-grazing zooplankton ultimately leads to high

algal biomass (Scheffer, 1998).

1.5 Subspecies and strains of Cyprinus carpio

Wild common carp are typically torpedo-shaped, full-scaled, and coloured

silvery-black or grey, olivegreen or yellow-brownish on the dorsal surface, softening to

pale yellow or cream on the ventral surface and flanks (Kirpitchnikov, 1981; Balon,

1995; Lintermans, 2007). Variations in scale morphology, colour and body shape,

however, are common in both wild populations and domestic strains. Domestic common

carp are typically rounder and plumper-bodied than wild carp. Feral population of

domestic common carp, however, revert to a wild-type body shape soon after

establishment (Balon, 1995). Traits such as dwarfism, the absence of ventral fins, the

presence of an additional fin, elongated fins and a dolphin-like head have also been

reported in both wild and domestic populations (Kirpitchnikov, 1981; Wang and Li,

2003). Owing to a large geographic range, a long history of culture and artificial

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selection by humans for aquaculture and ornamental

varieties of C. carpio (USGS, 2005) which

Kirpitchnikov (1967) recognized four subspecies of

carpio (Europe), C. c. aralensis

c. viridiviolaceus (South East Asia). But, Balon (2006) suggested that

subspecies could be clearly recognized:

(East Asia). Kirpitchnikov (1999) then questioned t

Most recently, Kottelat (2001) considered the common cultured carp in S

to be a distinct species, C. rubrofuscus

populations in Eurasia is shown in figure 1.5.

Figure 1.4. Ranges of wild common carp populations in Eurasia

1999; Chistiakov and Voronova, 2009).

There are about 30-35 strains of domesticated common carps in Europe.

strains are maintained in China.

have a broken pattern of unusually large scales or

and leather carp respectively. If the common carp h

Cyprinus carpio

Cyprinus carpio

Cyprinus carpio

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selection by humans for aquaculture and ornamental purpose there are a number of

(USGS, 2005) which exhibit much morphological variation

Kirpitchnikov (1967) recognized four subspecies of common carp viz.

C. c. aralensis (Central Asia), C. c. haematopterus (East Asia) and

(South East Asia). But, Balon (2006) suggested that

subspecies could be clearly recognized: C. c. carpio (Europe) and C. c. haematopterus

(East Asia). Kirpitchnikov (1999) then questioned the validity of C. c. viridiviolaceus.

lat (2001) considered the common cultured carp in South East Asia

C. rubrofuscus. The geographical range of wild common carp

shown in figure 1.5.

. Ranges of wild common carp populations in Eurasia (from

1999; Chistiakov and Voronova, 2009).

35 strains of domesticated common carps in Europe.

in China. Sometimes genetic variants are found in the wild th

have a broken pattern of unusually large scales or no scales at all, known as mirror carp

and leather carp respectively. If the common carp has only a single row of scales it is

Cyprinus carpio carpio

Cyprinus carpio haematopterus

Cyprinus carpio viridiviolaceus�

purpose there are a number of

logical variation.

common carp viz. Cyprinus carpio

(East Asia) and C.

(South East Asia). But, Balon (2006) suggested that only two

C. c. haematopterus

C. c. viridiviolaceus.

lat (2001) considered the common cultured carp in South East Asia

range of wild common carp

. Ranges of wild common carp populations in Eurasia (from Kirpitchnikov,

35 strains of domesticated common carps in Europe. Many

Sometimes genetic variants are found in the wild that

no scales at all, known as mirror carp

as only a single row of scales it is

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called a line carp (USGS, 2005). The nishikigoi, or koi as it is commonly known as in

the United States, is also a type of C. carpio, as are the Oujiang color carp and the long-

fin carp. ‘Mirror’ scales are a common feature of domestic common carp strains. These

scales are larger and shinier than ordinary scales, and usually do not covers the entire

body (Kirpitchnikov, 1981). The absence of normal scales has been favoured by

artificial selected in domestic fish to make them easier to de-scale for cooking

(Michaels, 1998).

The colour variations of common carp include golden, red, blue, orange, steel,

green, albino, yellow, lemon-yellow, green, violet and brown which are seen in both

wild and domestic populations (Kirpitchnikov, 1981; Wang and Li, 2003). Red, golden

and orange individuals are found amongst domestic and wild populations in both

Europe and Asia (Kirpitchnikov, 1981; Balon, 1995a). Moreover, the selective breeding

has led to the production of fancy carp, or koi, in Japan which are now available in a

wide range of colours, scale morphologies and body shapes.

In physical shape, common carp are characterized by two types: one with big

stomach and other with slender body. The body is elongated and somewhat compressed

and flat on both sides. The mouth can be extended forward as it opens up. The lips are

thick and smooth. Two pairs of fleshy whiskers (barbels) are present on either side of

the mouth, with the posterior pair being longer than the anterior pair (Koehn et al.,

2000). Dorsal fin base long with 17-22 branched rays and a strong, toothed spine in

front; dorsal fin outline concave anteriorly. Anal fin having 6-7 soft rays and anal fin

spines with sharp spinules. The scales are large and cycloid with 33–40 scales along the

lateral line and scales are absent on the head. The colour of common carp is genetically

determined, but some environmental effects, such as colloid content of water and the

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age of fish influence the shading of inherited colouring. The colour is variable, wild

carp are brownish-green on the back and upper sides, shading to golden yellow

ventrally. The fins are dusky, ventrally with a reddish tinge. Golden carp are bred for

ornamental purposes. Other traits are forked tail (caudal fin); no teeth in the mouth;

three rows of pharyngeal teeth on the lower element of the last gill arch, the outer two

rows of these pharyngeal teeth each having one tooth and the inner row having three

teeth (1,1,3:3,1,1 arrangement, which separates common carp from many other Cyprinid

species). Pharyngeal teeth are a distinguishing characteristic in the Cyprinid family,

both by structure and number, but within the strains of common carp there are no

remarkable differences (Bakos and Gorda, 2001).

Morphological description of strains includes the qualitative characters

determining the external features and also taxonomic classification (FAO, 2005). The

scaliness of common carp as a determining factor consists of four different basic forms:

scaly, mirror (scattered), linear and leather (naked) varieties. These types of scaliness

are determined genetically by four alleles at two loci, designated Ss and Nn, which

display Mendelian inheritance. The scaly carp results from the SS, nn and Ss, nn

combinations. The ancient, primitive populations and the oldest cultured forms are

covered with a regular pattern of scales. The mirror carp results from the homozygote

recessive ss, nn genotype exclusively. The typical mirror pattern is a single unbroken

row of scales on the top of the back, some scales near the tail and at the base of fins.

Preferably there are no scales along the lateral line or scattered across the surface of the

body in the mirror carp. The linear carp is basically similar to the mirror, but the lateral

line is completely covered by a wide line of scales. This is determined by the SS, Nn

and Ss,Nn genotypes. The leather carps result from the ss, Nn genotype and are

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absolutely scaleless. Irregularly, a few scales can be found at the base of fins.

Transitional forms of scaliness similar to linear or leather varieties can sometimes be

observed in mirror carp (ss, nn genotype), but these are called strongly- or slightly-

scaled irregular mirror or scattered carps (Bakos and Gorda, 2001).

1.6 Distribution of Cyprinus carpio

The common carp is perhaps the highly distributed fish all over the world. The

original natural distribution of common carp was restricted to a narrow belt in central

Asia within latitude 35˚-50˚N and longitude 30-135˚E and altitude 300m above sea

level (Jhingran and Pullin, 1998). It is now distributed in Western Europe throughout

Eurasia to China and Southeast Asia and from Siberia to Mediterranean and India. In

the past two centuries, common carp was introduced into Africa and America, which

make it one of the most important aquaculture species worldwide with an annual global

production of 3.4 million metric tons (FAO, 2007). As per FAO (Food and Agriculture

Organisation) database, common carp has been introduced in 110 countries while it is

native to 24 countries. Common carp can tolerate a variety of conditions but are

generally found in lakes and slower flowing rivers with soft bottom sediments (MD

DNR, 2008). They can live in fresh to brackish water and thrive from 20 to 60 degrees

North and South. C. carpio is one of the first fish species to be introduced into other

countries with human aid and now enjoys global distribution (MD DNR, 2008).

Fishbase.org (Froese and Pauly, 2008) has a comprehensive list of the status of common

carp in every country. The status of common carp is shown in three categories: native,

introduced, and not-established (Figure 1.5). Basically "native" means that carp live in

an area independent of human interference and have free-living and self-maintaining

populations, "introduced" refers to wild populations of carp are established but only

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because at one time people brought them there, and

conditions where carp are found in a country but ar

self-maintaining populations.

With the help of radiotracking Koehn and Nicol (199

is a mobile species. Large movements occurred both

individuals moving up to 230 kilometres between Yar

Murray River in Australia in

the year apparently independent of water temperatur

Figure 1.5. Global distribution of common carp (source:

and map designed by Joshua Ro

1.7 Culture of Cyprinus carpio

The Cyprinus carpio

food. They have been reared in ponds in China as ea

(B.C) (Horvath et al., 2002). Buddhist monks were probably responsible fo

distribution of carp from China and Vietnam through

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because at one time people brought them there, and "not established" refers to

conditions where carp are found in a country but are not widespread in free

ations.

With the help of radiotracking Koehn and Nicol (1998) showed that common carp

is a mobile species. Large movements occurred both upstream and downstream, with

individuals moving up to 230 kilometres between Yarrawonga and Barmah on the

Australia in only a few months. These movements occur throughout

the year apparently independent of water temperatures as low as 8°C.

. Global distribution of common carp (source: Rearranged from Fishbase.org

Joshua Robert Leisen).

Cyprinus carpio

Cyprinus carpio has been one of the oldest domesticated species of

food. They have been reared in ponds in China as early as the 5th century

2002). Buddhist monks were probably responsible fo

distribution of carp from China and Vietnam throughout south–east Asia. In Europe, the

"not established" refers to

e not widespread in free-living and

8) showed that common carp

upstream and downstream, with

rawonga and Barmah on the

only a few months. These movements occur throughout

Rearranged from Fishbase.org

has been one of the oldest domesticated species of fish for

rly as the 5th century Before Christ

2002). Buddhist monks were probably responsible for the

east Asia. In Europe, the

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domestication of carp was started by monasteries in the 12th century. Balon (1995a)

argues for an even older domestication of common carp in Europe, suggesting that

common carp were first domesticated by the Romans in the 1st and 2nd centuries

Christian Era (C.E). This argument is based on evidence that the Romans maintained

ponds for freshwater fish, and that common carp were an important food source in

Roman settlements along the River Danube. There is, however, no direct evidence to

support this theory. The common carp was a luxury food in the middle and late Roman

period, and it was consumed during fasting in the middle Ages. The fish were kept in

storage ponds by the Romans, and later in fish ponds constructed by Christian

monasteries. In this European practice the common carp were kept in monoculture.

Balon (1995a) also disputes early domestication of common carp in China, arguing that

the fish stocked in early Chinese ponds could have been other carp species, such as

grass carp, silver carp or the Indian major carps, rather than Cyprinus carpio. While it is

difficult to verify exactly which species were reared in ancient China, there is currently

a wealth of aquaculture carp strains in China that have been derived from indigenous

wild populations and have a long history of cultivation (Kohlmann et al., 2003; Zhou et

al., 2004a; Zhou et al., 2004b). Xingguo red carp, for example, have been cultivated for

approximately 1,300 years (Zhou et al., 2004a). Even if common carp domestication in

China does not date back to the B.C.E. period, it has been in practice in this region for

over 1,000 years. Today common carp are a globally important species. The common

carp was introduced in several countries of East, Middle and West, as this fish was

found to be the easiest to culture intensively. Although in America and Canada its

culture did not flourish, its cultivation became very popular and widespread in Europe,

Asia and Israel. Now, India is also a leading producer of common carp. Being fecund

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and robust, they are ideal for aquaculture and as such, are farmed extensively

throughout Eurasia, and to a lesser extent in North and South America (Zambrano et al.,

2001) and Africa (Costa-Pierce et al., 1993). In Asia they are typically grown in

polyculture ponds with 3-5 other fish species, each exploiting a different ecological

niche in the pond (Koehn et al., 2000). The harvesting of common carp for food, both

from the wild and from aquaculture, has been growing steadily since the late 1970s

Common carp are subsequently an important source of protein and provide income for

many people. When culturing began, wild forms of common carp from ancient

populations dominated. Some of them exist up to the present day as elongated scaly

forms of wild carps enriching the local fish fauna, but most cultured common carp now

look different from their ancestors.

The culture practices of common carp is vary from place to place and country to

country; these may be classified as pond culture, cage culture, culture in paddy fields,

culture in sewage-fed water, culture in streams, culture in closed recirculating water

system and culture combined with duck raising. Cultivation of common carp is

practised as monoculture as well as poly-culture. The common carp is preferred in the

culture system because of some attributes such as i) it is a very hardy fish; it can tolerate

wide pH range, salinity range and temperature range; and high turbidity, ii) fish is

omnivorous; iii) fish can be easily flattened on cereals and leguminous seeds, iv) fish

feeds well on a variety of artificial foods, v) fish is easily induced to spawn in captivity,

vi) fish does well as a constituent of poly-culture vii) fish responds well to selective

breeding and hybridization, making improvements feasible in the race viii)fish is found

to be more economical to raise. Another impetus to the culture of common carp is the

suitability in poly-culture practices. The common carp is an omnivorous feeder and

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successfully used in mixed rearing. The yield of such polyculture is often very high as

compared to that of monoculture in a pond. In polyculture, common carp is reared with

tench (Tinca tinca) in Yugoslavia; roach (Rutilus rutilus) in France, mullet and tilapia in

Israel, gold fish and bream (Abramis brama) in Russia (Srivastava, 1995).

1.8 Breeding of Cyprinus carpio

Common carp breeds once annually in temperate waters but several times in a

year in tropical waters. This disadvantage of temperate waters can be made over with

application of the induced breeding technique. In tropical waters, the availability of

spawn is assured throughout the year. It takes only three months for both sexes to be

ready for the next spawning after the last one (Vilizzi and Walker, 1999). In India, as

many as five spawning in a year have been recorded in the case of common carp.

Widespread adoption of common carp culture in tropical and semi-tropical waters is

attributed to this single advantage; common carp not only competes well with

indigenous species native of the place on this point but even commands preference over

the latter. In the tropics, common carp attains sexual maturity in the first year. Sexes are

distinguished with great difficulty. Whereas older sexes are relatively easily identified

due to the presence of tubercles on the side of the head and on the paired fins of males,

young sexes can be recognized only after stripping of gonadal products. Fecundity

varies according to size. A typical adult common carp can lay 300,000 eggs in a single

spawning. The number of eggs varies from 36,000 to 2,000,000 in a single spawning

season by each female. Although carp typically spawn in the spring, in response to

rising water temperatures and rain fall, carp can spawn multiple times in a season. In

natural conditions spawning are stimulated in two ways: i) use of water slightly warmer

than water of pond where breeders were stocked, and ii) real plants (Hydrilla, Naja or

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similar weeds) or artificial plants and other egg collecting devices (Kakaban of

Indonesia) (Srivastava, 1995). In commercial operations, spawning is often stimulated

using a process called hypophysation. In such condition, common carp generally breeds

within 6 to 10 hrs after being released in the breeding pool and by morning, the egg

collectors could be seen with millions of eggs. Eggs are adhesive and deposited onto

plant material such as submerged plants, tree roots, roots of undercut banks, leaf litter,

and/or logs in a mass or singularly (Wang, 1986) in spring to early summer. Eggs are

generally round to oval and either clear or tinted yellow. Eggs are abandoned by the

female and hatch in 3 to 5 days after being laid. In artificial breeding the eggs are then

transferred to the hatching hapa. Hatching is best achieved in a cloth hapa. Fertilized

eggs look a dirty yellow in colour and may be easily distinguished from the dead or

unfertilized eggs which are opaque and white. Hatching occurs in 46 to 48 hours at 28

to 310C. If the water temperature is less than this, the incubation period prolonged in

temperate climate at 200C hatching takes a much longer period extending even up to

144 hours. The just hatched larvae attach to walls or plants by means of their cement

glands. When the yolk sac is absorbed they become free swimming and begin to feed.

Paucity of food supply may lead to heavy mortality. Transfer to nursery ponds may be

done within the first three weeks of spawning. Females may spawn several times in one

season. Juvenile carp live in shallow floodplain habitats and are more abundant where

the density of adult carp is low (Srivastava, 1995). Growth rates of common carp vary

greatly between different regions, depending on temperature, food availability and

population density. Common carp grow rapidly and reach 10 to 13 centimeters in length

within the first year of life (Steiner, 2000). Common carp have been reported to live up

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to 20 years and reach a maximum weight of 60 pounds (27.216Kg), though most fall

between 1(0.4536Kg) and 10 pounds (4.536Kg) (Wang, 1986).

The embryonic development of common carp takes about 3 days at 20-23 °C.

Under natural conditions, hatched fry stick to the substrata. About three days after

hatching the posterior part of the swim bladder develops, the larvae swim horizontally,

and start to consume external food with a maximum size of 150-180 µm (mainly

rotifers). Gonad weight in mature females is between 15 and 30 % of total body mass.

Males have relatively large testes (5-10% of BW). Egg size averages 1000 eggs /gram

(Balon, 1995a). Common carps reproduce in spring time, and spawn only once in

temperate climates. Under laboratory conditions, (see earlier) carp females can be

stripped every 8 weeks. Males can be stripped every 10 days. Ovulation is induced with

carp pituitary, either as crude preparation, or as extract, in two injections. Stripped eggs

have limited storage time (2-4 hours at room temperature). Milt can be diluted in

extenders, and stored at 0-4ºC for several days. Eggs are degummed prior to fertilization

and incubated in conical upflow jars. Hatching is temperature dependent and takes place

after 3-5 days of incubation (range for 18 - 25ºC). Common carp may spawn throughout

the year in tropical areas of India, with peaks in January-March and July-August

(Linhart et al., 1995). Breeding is carried out in hapas, cement tanks or small ponds.

Submerged aquatic plants are used as substrata for egg laying. When the fry are 4 to 5

days old, they are stocked into nursery ponds. Common carp are stocked with Chinese

carps, and/or Indian major carps, tilapia, mullet, etc., in polycultural systems. This

constitutes a natural food and supplementary feed-based production method, in which

fish that have different feeding habits and occupy different trophic niches are stocked

into the same ponds. The frequent application of manure or fertilizers and the proper

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species ratio, make the maintenance of productive p

organisms, and the maximal utilization of the produ

(Jhingran and Pullin, 1985;

1.9 Global production of

Globally, common carp is a major culture species, a

cyprinid production. In 2007, world production of c

million ton from approximately 80 countries and re

global freshwater aquaculture increased by an avera

between 1980 and 2007 (Jeney and Jian, 2009). The g

Cyprinus carpio from 1950 to 2010

Figure 1.6. Graph showing increased global aquaculture produc

from 1950 to 2010. (Source: FAO Fishery Statistic)

India is the sixth largest producer of fish in the

second in world aquaculture produc

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species ratio, make the maintenance of productive populations of natural food

organisms, and the maximal utilization of the productivity of pond ecosystem possible

; Kestemont, 1995; Parihar, 1999).

Global production of Cyprinus carpio

Globally, common carp is a major culture species, accounting for 15.2% of all

cyprinid production. In 2007, world production of cultured common carp reached 2.9

million ton from approximately 80 countries and regions, which was 9.9% of total

global freshwater aquaculture increased by an average global rate of 7.9% per year

between 1980 and 2007 (Jeney and Jian, 2009). The global aquaculture production of

from 1950 to 2010 is shown in Figure 1.4.

. Graph showing increased global aquaculture production of Cyprinus carpio

from 1950 to 2010. (Source: FAO Fishery Statistic)

India is the sixth largest producer of fish in the world (6.41 million tonnes) and

second in world aquaculture production (2.22 million tonnes) (Basavaraja,

opulations of natural food

ctivity of pond ecosystem possible

ccounting for 15.2% of all

ultured common carp reached 2.9

gions, which was 9.9% of total

ge global rate of 7.9% per year

lobal aquaculture production of

Cyprinus carpio

world (6.41 million tonnes) and

Basavaraja, 2007). Carps

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are the most widely cultured freshwater fish in India. Mixed species culture is most

common where the three species of Indian major carps (IMC), i.e. catla (Catla catla),

rohu (Labeo rohita) and mrigal (Cirrhinus mrigala) are cultured with three exotic carp

species, namely, silver carp (Hypophthalmichthys molitrix), grass carp

(Ctenopharyngodon idella) and common carp (Cyprinus carpio). However, the number

of species and their combination vary depending on seed availability, consumer

acceptance and ability to grow well in different environments. The common carp is

perhaps the world’s most extensively cultured species. The Bangkok Strain of common

carp is one of the most widely farmed fish globally. In India, it is one of the four fish

species commonly farmed either singly or in combination with the IMCs and also with

the Chinese carps, grass carp and silver carp. Cyprinus carpio is an omnivorous fish,

capable of withstanding fluctuation in the water levels and other adverse environmental

factors. It grows almost at par with the fastest growing IMC, the catla. However,

sometimes, due to its prolific breeding habit, it offsets the stocking density of the

culture pond, resulting in a production of undersized fish of very low market value

(Basavaraja, 2007). Detailed studies on the cultivable aspects of common carp have

been carried out at the Pond Culture Division of Central Inland Fisheries Research

Institute (CIFRI), Barrackpore, India. The common carp breeds naturally in confined

waters. Spawning occurs in shallow marginal weed-infested areas. It spawns throughout

the year in a tropical country like India, with two peak breeding seasons, one lasting

from mid-January to March and the other during July and August. However, diverse

breeding techniques of this species have been described (Hora and Pillay, 1962;

Alikunhi, 1957; Alikunhi, 1966).

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1.10 Genetic variability of Cyprinus carpio

Common carp has been cultured for several centuries, initially in temperate European

and Asian countries, and has been significantly altered by deliberate and accidental

genetic changes over this long period of culture (Basavaraju et al., 2004). In some

tropical regions, the common carp adapt to local conditions through unconscious

selection, genetic drift and inbreeding, commonly resulting in a deterioration of culture

performance. In China, variants of C. carpio have been artificially selected for

ornamental purposes. Release of exotic fish into the wild water bodies of a country can

have genetic impacts at three levels: on the individuals released, on specific native

individuals or on closely related indigenous species and the effects can be either direct

or indirect. Direct impacts include those that operate on a species by initiating changes

in gene flow, through hybridization and introgression. Indirect effects are primarily

those caused by inadequate number of spawners, either through release of a small

number of individuals, or in the indigenous species through ecological processes such as

competition, predation, new diseases or parasites. Such genetic effects may lead to a

loss of indigenous fish populations and their genetic diversity. Fishes have a greater

potential for successful hybridization without sterility than either mammals or birds, and

this may lead to complex introgression when domesticated fishes meet the wild stocks.

Exotics may thus interbreed with either native congeners or with other aliens. Examples

of genetic deterioration due to alien fish species introductions and transfers within

aquaculture activities are very numerous (Arthington, 1991). The environmental impact

of such deterioration is evident as aquaculture facilities are, except in very rare

situations, connected with the hydrographic system (rivers, lakes) and both accidental

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stocking and interactions with wild populations may occur quite often. The most

frequent cases concern introgressive hybridization and loss of genetic variability.

Hybridisation can also lead to changes in chromosome number (ploidy), creating

lineages that have one or two complete sets of chromosomes from two separate species

(allopolyploid lineages). These lineages can be capable of, or limited to, asexual

reproduction (parthenogenesis). They can subsequently have greatly elevated levels of

reproductive output, as all individuals are capable of producing offspring (Billington

and Hebert, 1991). In Africa and Latin America, there has been a widespread breeding

of different genetic strains, particularly of the tilapiine cichlids, which has already

resulted in a considerable mixing of the gene pool. Indirect effects arise from the impact

of reductions in population size on genetic diversity, either through release of too few

individuals (founder effect), high mortality due to adaptation to new environments

(population bottleneck) or ecological effects on native fish through such forces as

competition, predation or transfer of diseases or parasites from introduced fish. The

common carp genetic studies had been performed in the last few years, which focused

on development of genetic markers (Zhou et al., 2004a; Wang et al., 2007; Zhang et al.,

2008; Kongchum et al., 2010) for breeding and genetic evaluation, construction of

genetic maps (Sun and Liang, 2004; Cheng et al., 2010) and physical map (Xu et al.,

2011a), collection of a large set of ESTs (Christoffels et al., 2006) and microRNA (Yan

et al., 2009), construction of bacterial artificial chromosome (BAC) library (Li et al.,

2011) and collection BAC-end sequences (BES) (Xu et al., 2011b), transcriptome study

with cDNA microarrays (Moens et al., 2007), characterization of functional genes (Wan

et al., 2011) and quantitative trait loci (QTL) analysis (Zhang et al., 2011).

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1.11 Phylogeography

Phylogeography is concerned with the principles and processes governing the

geographical distributions of genealogical lineages, especially those at the intraspecific

level (Avise, 1998, 2000). Phylogeographic study is undergoing a major expansion as

the range of convenient genetic markers available to study geographic variation

increases. Ultimately, the aim of phylogeography might be defined as a means to

understand microevolution and speciation in its geographic or spatiotemporal context.

Understanding the geographical context of the observed pattern is essential in the

development of evolutionary models of real organisms (Kidd and Michael, 2006).

Detecting coincidence or concordance of geographic variation in genotypes, or their

genealogies, and the environment is therefore at the heart of phylogeographic inference.

Geographical concordance between genealogies may be across sequence characters

within a gene, between significant genealogical partitions across multiple genes within a

species, or in the geography of gene-tree partitions across multiple co-distributed

species. The latter has been called comparative phylogeography and may provide a

‘bridge’ between the historically separate disciplines of phylogeography and historical

biogeography (Bermingham & Moritz, 1998). A wider definition of phylogeography

includes genetically controlled traits, such as morphology or behaviour, for which

comparable concordance patterns can be studied (Avise, 1998). Phylogeographers must

manipulate a wide range of data and information types including ‘raw’ character

matrices and DNA sequences, derived trees and network graphic representations,

coalescent hypotheses as well as external contextual data describing environmental

variation and landscape structure. Phylogeography therefore utilizes a heterogeneous set

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of quantitative and qualitative data obtained from a wide variety of sources with

differing data structures, e.g. trees, networks, spatial grids or vector points, lines or

polygons. Phylogeography integrate both phylogeny and geography within a

quantitative analytical framework that encompasses the diverse aspects of

phylogeographic concordance. Without such a framework, phylogeography will remain

essentially a narrative biogeographic approach (Humphries, 2000). In the phylogenetic

or population genetic approach, graphical phylogenetic trees, networks or clades are

calculated from the observed variation data. These graphical representations of

evolutionary relationships are subsequently compared to external information that could

be another trait of the same organism, a trait or distribution of a different organism, or

an environmental variable, to identify congruent spatial and phylogenetic pattern

facilitating the inference of, usually qualitative, historical scenarios (Taberlet et al.,

1998; Hewitt, 1999). Population genetics in relation to biogeography have been studied

by several authors in different ichthyo-faunas. For example, phylogeographic studies of

the fishes of the south-eastern United States was done by Bermingham and Avise

(1986), Nearctic North America by Bernatchez and Wilson (1998), Central America by

Bermingham and Martin (1998), and Australia by Hurwood and Hughes (1998).

1.12 Biochemical composition

Fish is one of the important food sources as it includes essential fatty acids, amino

acids and some of the principal vitamins and minerals in sufficient amounts for healthy

living (Borgstrom, 1961). It has been widely accepted as a good source of protein

(Andrew, 2001) and it is rich in essential amino acids (lysine, methionine, cystine,

threonine, and tryptophan). Amino acids are the building blocks of proteins and help to

maintain health and vitality. There are 20 amino acids that can be found in the human

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body, 18 of which are important in human nutrition. Eight amino acids cannot be

synthesised de novo by humans and other mammals and hence must be supplied in the

diet; therefore they are called essential amino acids. The nutritive quality of any food

protein is determined by the i) the content of essential and nonessential amino acids; ii)

the mutual proportions of specific essential amino acids, which preferably should be

similar to that found in the proteins of the body; iii) the energy supplied, which is

essential for protein synthesis in the body; iv) the digestibility of the protein (Boisen et

al., 2000). Fish meat contains significantly low lipids and higher water than beef or

chicken and is favored over other white or red meats (Neil, 1996). In human nutrition,

fatty acids such as linoleic and linolenic acids are important for preventing skin diseases

and are considered essential as they cannot be synthesized by the organism. However,

fish oils contain other "essential" polyunsaturated fatty acids which act in the same way

as linoleic and arachidonic acids (Elvevoll and James, 2002). Fish lipids are well known

to be rich in long-chain n-3 polyunsaturated fatty acids (n-3 PUFA), especially

eicosapentaenoic acid and docosahexaenoic acid. Long chain, n-3 PUFA cannot be

synthesized by humans and must be obtained from the diet (Alasalvar et al., 2002).

Minerals are essential nutrients, they are components of many enzymes and metabolism,

and contribute also to the growth of the body (Glover and Hogstrand, 2002). These are

obtained by human from different food sources. Fishes are important source of

minerals. Minerals are chemical constituents used by the body in many ways. Although

they yield no energy, they have important roles to play in many activities in the body

(Malhotra, 1998). Every form of living matter requires these inorganic elements or

minerals for their normal life processes (Hays and Swenson, 1985). The importance of

mineral elements in human, animal and plant nutrition has been well recognized.

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Deficiencies or disturbances in the nutrition of an animal cause a variety of diseases and

can arise in several ways (Soetan et al., 2010). Minerals play a critical role in various

body functions and are necessary to sustain life and maintain optimal health for humans

and animals. Calcium and phosphorus as macro-nutrient are the most important

elements in exoskeleton, bone, scales, and teeth formation and responsible for

maintaining the acid-base equilibrium (Watanabe et al., 1997). In addition calcium is

required for blood clotting process while phosphorous is a component of

deoxyribonucleic acid (DNA), ribonucleic acids (RNA), nucleotide and act as a co-

factor for different enzymes (Davis and Gatlin, 1996). For example, manganese is

considered to be an activator for different enzymes such as leucine-aminopeptidase and

zinc activates the alkaline phosphatase enzyme. Some trace elements serve as

metalloproteins (e.g. iron in haemoglobin, copper in haemocyanin) or metalloenzymes

(e.g. zinc serves as a metalloenzyme for carbonic anhydrase, carboxypeptidases,

glutamic dehydrogenase and a variety of other enzymes (Clark et al., 1987).

Biochemical composition of flesh is a good indicator for the fish quality, the

physiological condition of fish and habitat of fish (Shamsan and Ansari, 2010;

Ravichandran et al., 2011). Fish of various species do not provide the same nutrient

profile (Takama et al., 1999) and the nutritive value of a fish varies with season

(Varljen et al., 2003).

1.13 Impact of Exotic Fish

Non-indigenous species may affect indigenous species by competing for

resources, preying on native fauna, transferring pathogens, or significantly altering

habitat (Pimentel et al., 2000). In India, tilapia (Oreochromis mossambicus) was

introduced in 1952 in certain as ponds and reservoirs, but the species spread all across

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the country within a few years due to its prolific breeding and adaptability to wide range

of environmental condition. A number of other exotic fish species such as Aristichthys

nobilis, Clarias gariepinus, Pangasianodon hypophthalamus, Oreochromis niloticus,

Pygocentrus natterei, Piaractus brachypomus etc have been introduced illegally in

India (Goswami, 2000). Tilapia is an omnivorous grazer that feeds on phytoplankton,

periphyton, aquatic plants, small invertebrates, benthic fauna which causes loss of

biodiversity in aquatic ecosystem. Overpopulation of the species affected the fisheries

of several reservoirs in Tamil Nadu, Kerala, Karnataka, Rajasthan and West Bengal and

also posed threat to species like mahseers (Tor tor and T. putitora), which are on the

verge of extinction (Thakur, 1996). Exotic fish Grass carp, Ctenopharyngodon idella

has been found to consume plant material, and uprooting macrophytes which cause

erosion of bank. During flood this fish cause huge loss to the paddy field. In pond they

mostly consume tender species and tougher aquatic plants remain untouched. This

causes modification of aquatic plant communities which could significantly affect

trophic structure of aquatic ecosystem (Choudhury et al., 2012). Due to sharing of food

and aggressive behaviour, the exotic fishes can alter trophic relationships in aquatic

communities in different ways such as increase the amount of prey available to native

predators and can reduce the amount of forage available to native species (Moyle,

1986). Diseases caused by bacteria, viruses, and parasites are often conveyed along with

exotic species and may pose threat to a native community by transfer of parasites from

exotic to native fishes. Rainbow trout, Oncorhynchus mykiss from western North

America have carried furunculosis to Europe. North American fathead minnow

Pimephales promelas has been proved to introduce Yersinia ruckeri, which is the

causative agent of red mouth disease to parts of northern Europe. The cause of outbreak

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of the parasitic fluke in Norway was due to introductions from farmed salmonids to

wild population (Langdon, 1989; Whittingham and Chong, 2007).

Fishes have great potential for successful hybridization without sterility, and may

produce long-lasting hybrids in the wild. Indigenous species may interbreed with

introduced exotics. Hybridization between exotic and native fishes results loss or

reduced genetic integrity (Hickley and Chare, 2004; Gunnell, 2008). The impacts can be

significant and include loss of pure forms, reduced mating efficiency, less fit stocks

through the loss of adapted gene complexes, disruption of migration (spawning and

feeding) patterns, altered behaviour, changes in life-cycle timing, lower reproductive

output and other effects. Welcomme (1988) found that the translocation of hatchery

reared brown trout Salmo trutta is genetically inferior to wild-bred stock.

Another important report on the impact of introduction of exotic fish is the

elimination of local species. The larvivorous fish Gambusia has been called the “fish

destroyer”, and is said to replace native species aggressively (Singh and Lakra, 2011).

High fecundity power of some exotic fishes causes disappearance of some local species

(Goswami, 2006). In Loktak Lake of Manipur, Cyprinus carpio has now replacing the

endemic fish species particularly Osteobrama belangeri (Singh et al., 2010a). Koehn

(2004) reported that the invasion of Cyprinus carpio in Australia has already causing

serious implications to the native fish communities. Some exotic fishes cause

degradation of aquatic habitat. The introductions of the goldfish and common carp have

affected the ecosystem, by greatly increasing turbidity (Crivelli, 1995; Choudhury et al.,

2012). Habitat degradation and consumption of large amount of macro invertebrates by

common carp affects natural balance of aquatic system (Wilcox and Hornbach, 1991).

The increase in turbidity due to the presence of common carp reduces the light

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availability for aquatic plants, which subsequently reduces survival rate of macrophytes

and create an unfavourable ecological condition in pond (Meijer et al., 1990).

1.14 Invasiveness of common carp

An invasive species can be defined as any species that has been translocated from

its indigenous environment to a new environment and successfully established a self-

sustaining population. Common carp is regarded as invasive species as it is

opportunistic omnivores and adjusted with varying dietary preferences according to

availability of the food (Parks, 2006). It is currently considered to be one of the world’s

most ecologically harmful invasive species (Lowe et al., 2004). Its impacts arise mainly

from the ability to alter aquatic habitats through high levels of excretion and by

disturbing the bottom sediments of water bodies; often resulting in increased turbidity,

degraded water quality and reduced macrophyte and benthic invertebrate densities

(Zambrano and Hinojosa, 1999; Parkos et al., 2003; Matsuzaki et al., 2007). In another

study it was found that introduction of exotic fish could affect the species diversity of

native fish species and could disrupt the food web function of the ecosystem (Jackson,

2002; Vander Zanden et al., 1999). The habitat changes caused by common carp (e.g.,

increased turbidity and loss of macrophytes) may influence small native fish and other

benthic fauna (Llewellyn, 1974). Common carp are currently considered as the worst

freshwater pest fish in both Australia and New Zealand (Chadderton et al. 2003, Koehn,

2004). In several countries it is considered as a problem because of their impacts on

water quality, soft-leaved aquatic plants and native fish populations. But yet the global

aquaculture production of Cyprinus carpio has been increasing in last few decades

(Figure 1.4).

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Table 1.1. Attributes of common cap as invasive species (derived from Koehn, 2004)

Attributes Details

Invasion history, widespread

distribution and abundance

Introduced and established throughout

Europe, Asia, Africa, North, south and central

America, Australia, New Zealand, Papua

New Guinea and some islands of Oceania.

Wide environmental tolerances Temperature tolerance ranges from 2 to

40.60C, salinity tolerances up to 14%, pH

from 5.0 to 10.5, and dissolved oxygen levels

as low as 0.4mg/L.

Early sexual maturity Males at 1 year, females at 2 years

Short generation time 2-4 years

Rapid growth Hatching of eggs is rapid (2 days at 250C)

and newly hatched carp grow very rapidly

High reproductive capacity High fecund broadcast spawners with egg

counts as high as 2 million per female

Broad diet Omnivore/detritivore

Gregariousness A schooling species

Possessing natural mechanism of

dispersal

A mobile species with fish moving between

schools. Dispersal can also occur with

downstream drift of larvae.

Commensal with human activity Bred as an ornamental (koi) and aquaculture

species, used as bait and some anglers.

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1.15 Introduction of Cyprinus carpio in India

Immediately after independence, the Govt. of India had decided to introduce

some exotic species of fish for various purposes such as to meet the demands of the

fish, combating malaria and other vector borne diseases and for ornamental purposes

etc. For this several exotic species have been introduced into India with proper

government approval and for specific intentions. However several other species of

exotic fishes were introduced without any approval or any studies which may be termed

as unintentional. The State is vulnerable to exotic invasion from neibouring country

Bangladesh and several exotic fish species have already invaded from it (Goswami,

2000). In India the common carp was introduced for composite fish farming in India to

increase fish production in ponds, tanks, lakes and reservoir (Srivastava, 1995).

In India, there are three varieties of common carps: viz i) common carps with

small scales regularly covered all over the body called scale carp Cyprinus carpio

communis, (ii) those with shining big scales irregularly covered all over the body called

mirror carp Cyprinus carpio specularis and (iii) those with only few scales on the body

called leather carp Cyprinus carpio. nudus. However, the scale and mirror carps have

become popular in India due to its ability to survive in hot climate. The colour varies

from gray to orange. In India, the mirror carp was introduced for the first time 1939

from Ceylon into Nilgiris. Later on they were introduced to Bangalore and in 1947.

(Yadev, 2006). The Scale carp was brought from Bangkok in 1957 and transplanted to

Cuttack. This Bangkok strain of common carp has been introduced in most of the

reservoirs and lakes of plains where it has been established (Shetty et al., 1989). The

Prussian strain of the common carp was introduced in Nilgiris (Tamil Nadu) in 1939

(Chacko, 1945) and this stock now comprises a mixture of scale carp (C. carpio

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communis), mirror carp (C. carpio specularis) and leather carp (C. carpio nudus). All

these varieties are mostly confined to the cold upland waters and do not generally breed

in the plains (Alikunhi, 1957). The Chinese stock of common carp which breeds freely

in the plains was introduced in 1957 in Cuttack, wherefrom its seed has been distributed

throughout India and its culture popularized (Alikunhi, 1966). Now, Common carp is

widely distributed throughout India have become the most abundant large freshwater

fish in India. Common carp become naturalised in India and has been increasing their

presence in the wild water bodies in India (Singh et al., 2010a).

Increased occurrence of common carp in the Ganga River was recorded and found

that common carp has established in the Ganga River as a pest through naturally

breeding populations which is now becoming the source for invaded to other places

(Singh et al., 2010b). Impacts of exotic fish in the Ganga River have been found to be

mild at present but it may cause habitat alteration, trophic structure alteration, and

hybridization in due course of time (De Silva et al., 2006; Lakra et al., 2008). In

Manipur, Cyprinus carpio has escaped into the Loktak Lake and is now replacing the

important local and endemic fish species particularly Osteobrama belangeri. The

catches of common carp fish production of Gobind Sagar reservoir in the state of

Himachal Pradesh have increased by 30% in the reservoir for the last eight years.

Progressive increase in the catch of common carp was recorded from two tonnes during

1992-93; the catches have increase to 24 tonnes during the year 2009-10

(http://hpfisheries.nic.in). Due to introduction of common carp in the lakes of Kumaon,

the catches of schizothoracids was found to drastically decline (Singh and Lakra, 2006)

and the production of common carp increased since 1985 (Shyam Sunder, 1998).

Besides common carp, a few other alien fish species have established their populations

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in the natural environment of India through natural reproduction. Out of over 30 exotic

food fish species, only carps, tilapia, hybrid catfish and white shrimp have been

commercially used for aquaculture. Grass carps and silver carps introduced into the

lakes and reservoirs for their characteristic feature of controlling excessive vegetation

and plankton bloom respectively (Welcomme and Vidthayanon, 2000). The exotic

fishes were meant mainly for aquaculture, which in due course moved into open waters

inadvertently or because of unawareness which may cause serious ecological problems

(King and Hunt, 1967).

1.16 Occurrences of Cyprinus carpio in Assam

In Assam, several exotic fish species viz. Cyprinus carpio, Ctenopharyngodon

idella, Hypophthalmichthys molitrix, Aristichthys nobilis etc are now available in all

rivers, tributaries and wetlands. However the common carp is found more abundantly

all over Assam. The fish catch reports shows that their numbers have been increasing in

all rivers and wetlands. The above mentioned four exotic species have now shared about

30 to 50% in few markets of Lower Assam. In North East India, the Brahmaputra,

Barak, Teesta, Chindwin and Kola dyne systems with large number of their tributaries,

connected wetlands, numerous hill streams and other streams and rivulets furnish a wide

variety of fish species inhabiting different ecological niches (Nath and Dey, 2000). The

common carp is being farmed in Assam along with Indian Major Carp (Choudhury and

Goswami, 2012). The C. carpio communis is the widely available strain of common

carp in India including Assam. The exotic fish species Cyprinus carpio communis is

now available in all rivers, tributaries and wetlands in Assam. The fish catch reports

shows that their numbers have been increasing in all rivers and wetlands. Various

studies indicate that common carp have great potential to further expand their range in

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India. Considering this, the present study was encompasses a preliminary survey of the

occurrences of exotic Cyprinus carpio communis in two major wetlands (beel) of

Assam.

Assam is blessed with abundant productive and diversified fresh water resources

to harbour various fish species and water birds. The Brahmaputra Valley of Assam

endowed with large number of fresh water bodies, locally called beels. The role of beel

or wetlands in conserving fish diversity has been widely acknowledged as these

ecosystems are used by fishes as a refuge for breeding, feeding and nesting purposes at

one or the other stage of their life cycle (Wetzel, 2001). According to the Directory of

Asian Wetlands (Scott, 1989), India has totally 27,403 wetlands, of which 23,444 are

inland wetlands and 3,959 are coastal wetlands. Wetlands occupy 18.4% of the

country’s area of which 70% are under paddy cultivation. The Wildlife Institute of

India’s survey reveals that they are disappearing at a rate of 2% to 3% every year

(NWCP, 2009). In Assam, beels cover an area of 101232 ha (Jhingran and Pathak,

1987). Beels are considered as one of the most renowned reservoirs of different kind of

fish species and contain a wide variety of peculiar animals and plants of their own.

Wetlands are a land-water linkage of great importance. In a natural system, water

reaches a wetland through rainfall, surface flows or groundwater discharge and leaves

by way of recharge to a groundwater aquifer, discharge to a watercourse, or

evapotranspiration. Wetlands vary in size and depth seasonally, annually, or over longer

time periods with changes in climate. Besides these, wetlands provide quality

environment to the region and accelerating the rural economy. In last two decades, the

indigenous fish populations in the wetlands of Assam have been affected by several

exotic fish species through niche overlapping and habitat degradation (Choudhury et al.,

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2012). The rapid growth of such exotic fish species may affect the indigenous fish

population through competition for food, shelter and breeding sites. The exotic fishes

have high fecundity power and easily adaptable to the environment of Assam. The

decreasing catch rate of several indigenous fish species in natural water bodies may be

due to rapid multiplication of exotic species (Choudhury et al., 2013). There has been

an increasing demand for exotic fish species in India due to high return. The exotic were

brought into the country with the objectives of broadening the aquaculture and

increasing the yield through better utilisation of trophic niches. Now these exotic fishes

have established in the natural water bodies of India including rivers and beels of

Assam through accidental escaping from captivity, flood or during transportation

(Choudhury et al., 2013).

1.17 Invasion of Cyprinus carpio in wetlands of Assam

Considering the approach of the present study, an attempt has been made to have

some information of invasion of Cyprinus carpio and other exotic fish, a preliminary

study was conducted to know the extent of invasion of exotic fish in two wetlands viz.,

Kapla beel and Urpod beel, two open types of wetlands connected with the Brahmaputra

river system. This was examined in two methods. Firstly, the total commercially caught

fishes in Kg was recorded and percentage of each group including exotic fish was

calculated thereof. The percentage of catch of common carp was recorded separately

along with the total catch. Secondly, calculation of Abundance Index of four exotic

fishes (Density of fish populations at each study site) in Urpod beel and common carp in

Kapla beel was done from total catch. In order to collect data on fish catch, field

investigation was conducted from January to December during 2011 at Urpod beel. The

fish production data of Kapla beel was studied from 2008-09 to 2011-12. All data was

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collected on weekly basis and then compiled as monthly basis. Data collections were

done from all important landing centres and market areas of the beel during 6:00AM to

5:00 PM. Fish species in study site were identified by using the keys given by Jhingran

(1975) and Fisher and Bianchi (1984). The abundance index of exotic fish was

calculated by using the following formula (Singh et al., 2010a):

AI (%) = n (k) x100/N

Where, AI = abundance index, n (k) = number of exotic fish caught at each study site,

N = number of all the fish species caught at that site.

1.17.i Invasion of Cyprinus carpio in Kapla beel

The Kapla beels/ wetland is the located at Sarukshetri mouza of Barpeta district of

Assam. It extends between latitude of 26018'12" to 26

025'7" N and between longitudes

of 91008'42" to 91

014'50" E. (Figure 1.7 and 1.9 A, B, C, D). The total area of the Kapla

Beel is about 642 Bigha (91 hectors). The whole area comprises three beels namely

Saru-Kapla, Salmara and Borkona which together constitute a greater Kapla Complex.

The Kapla beel is a beautiful perennial beel of Assam which harbours varieties of

piscean and avian fauna. The water level of the beel changes variably according to

season. It reaches an average height of 13-14 ft during mid rain seasons usually (July to

September), while water level falls to 7-9 ft during the dry season (October –June). This

beel holds a key position in the socio-economic life of surrounding human communities.

The beel act as the perspective spawning ground a variety of fish group including

Indian Major Carps. Kapla Beel harbours about 70 different species of fishes belonging

to 6 major orders like – Cypriniformes, Siluriformes, Channiformes, Perciformes,

Clupeiformes, Mastacembeliformes. Among these, the Indian Major Carps and exotic

carps Cyprinus carpio and Hypopthalmichthys molitrix are the dominant species.

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Figure 1.7. Location map of Kapla beel (www.google

Figure 1.8. Location map of Urpod beel of Assam

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Figure 1.7. Location map of Kapla beel (www.google map.com)

. Location map of Urpod beel of Assam (www.google map.com

Figure 1.7. Location map of Kapla beel (www.google map.com)

www.google map.com)

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Figure 1.9 . Photographs showing parts

beel (E, F) of Assam. The

and Cyprinus carpio communis

abundance has been increasing in the beels in recen

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showing parts of Kapla beel/wetland (A, B, C, D) and Urpod

e beels are the home many indigenous fish species

communis is a commonly available exotic fish species and the

abundance has been increasing in the beels in recent years.

/wetland (A, B, C, D) and Urpod

home many indigenous fish species in Assam

is a commonly available exotic fish species and their

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1.17.ii Fish catch data of Kapla beel

The Kapla beel is a natural habitat and breeding ground for many fish species

including Indian major carps. The beel harbour a large number of other fish groups such

as air breathing fish, minor carps, cat fishes and ornamental fishes. In the present studies

the various fish species found in Kapla beel have been recorded by dividing them into

seven groups namely, Indian Major Carps, Murrels, Catfish, Feather back, Common

carp, Other Exotic fish and Misc. The fish catch data that were collected from the beel

are presented in the Table 1.2. The total fish catch in the Kapla beel was 12,610 Kg,

9,620 Kg, 7,890 Kg and 5,480 Kg in the year 2008-09, 2009-10, 2010-11 and 2011-12

respectively. The total exotic fish catch percentage in the beel was 13.00% in the year

2008-09 and it reaches to 22.35% in 2011-12 (Table 1.2). From the studies it has been

observed that out of several exotic fish species, Cyprinus carpio is found abundantly in

the beel. In 2008-09 the catch percentage of Cyprinus carpio in the beel was 2.85% of

total fish which is become 4.10% in 2011-12. The fish catch statistics during the study

period indicated that the fishes belonging to the Indian Major Carps has been gradually

decreasing from 23.79% in the year 2008-09 to 18.61% recorded in the year 2011-12

(Figure 1.11 to 1.13). All the indigenous fish group populations are decreasing in the

four years. Once Feather back fishes especially Notopterus chitala was abundant in the

beel and in recent years their production has also been decreasing. Abundance index

(AI) of Common carp in Kapla beel during 2008-12 is shown in Figure 1.14 which has

been increasing year by year. Similarly other indigenous fish species like Aorichthys

aor, Wallago attu, Channa marulius, Channa striatus have also been decreasing

tremendously. The statistical data have clearly indicated that the overall production of

fish in the beel decreasing very rapidly and its last year’s production is less than half of

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the production of four years back. The decreasing is more prominent of fishes belonging

to the major and intermediate groups in the beel and on the other hand, the exotic fishes

especially Cyprinus carpio, Ctenopharyngodon idella, Hypothalmichthys molitrix and

Aristichthys nobilis have been increasing in the beel rapidly.

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Table 1.2. Production of various Fish group and their percentage in the Kapla beel of

Barpeta district of Assam during 2008-2012

Fish/fish

groups

2008-09 2009-10 2010-11 2011-12

Fish

catch

in Kg

% of

fish

catch

Fish

catch

in Kg

% of

fish

catch

Fish

catch

in Kg

% of

fish

catch

Fish

catch

in Kg

% of

fish

catch

Indian Major

Carps

3000 23.79 2060 21.41 1670 21.17 1020 18.61

Murrels 2080 16.49 1650 17.15 1200 15.21 780 14.23

Catfish 1900 15.07 1120 11.64 1150 14.57 930 16.97

Feather ack 1140 9.04 875 9.09 710 9.00 505 9.21

Common carp 360 2.85 280 2.91 250 3.17 225 4.10

Other Exotic

fish

1280 10.15 1230 12.78 1160 14.70 1000 18.25

Misc. 2850 22.60 2405 25.00 1750 22.18 1020 18.61

Total

Indigenous

fish

10970 87 8110 84.3 6480 82.19 4255 77.65

Total exotic

fish

1640 13 1510 15.37 1410 17.87 1225 22.35

Total fish

production

12,610 9,620 7,890 5,480

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Figure 1.10. Production of different fish group in Kapla beel

Figure 1.11. Total fish catch of Kapla beel duing 2008

0

5

10

15

20

25

30

2008-09

Indian Major Carps

Feather back

Misc.

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. Production of different fish group in Kapla beel during 2008

. Total fish catch of Kapla beel duing 2008-12

2009-10 2010-11 2011

Indian Major Carps Murrels Catfish

Common carp Other Exotic fish

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. Production of different fish group in Kapla beel during 2008-12

12

2011-12

Other Exotic fish

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Figure 1.12. Common carp catch in Kapla beel during 2008-12

Figure 1.13. Abundance index (AI) of Common carp in Kapla beel during 2008-12

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le 1

.3. A

bundan

ce i

ndex

(A

I) o

f ex

oti

c fi

sh C

om

mon c

arp

in K

apla

b

eel

duri

ng 2

008

-12

Yea

r Ja

n

Feb

M

arch

Ap

ril

May

Ju

ne

July

A

ug

Sep

t O

ct

Nov

Dec

M

ean A

I

2008-0

9

5.5

8

5.2

1

3.2

3

2.1

8

2.0

3

5.0

0

5.3

2

6.5

6

7.1

4

7.7

3

7.2

2

7.6

7

5.4

0

2009-1

0

6.5

5

5.1

8

3.4

6

2.1

7

2.6

2

6.7

5

8.0

9

10.4

5

10.6

6

9.3

8

9.1

1

8.3

2

6.8

9

2010-1

1

6.1

1

7.8

7

4.2

1

3.2

0

2.3

4

7.0

7

7.6

4

8.9

5

10.2

4

10.1

3

11.1

5

9.2

9

7.3

5

2011-1

2

7.1

2

9.6

8

5.1

0

2.2

8

2.0

6

7.5

5

8.7

2

10.1

5

11.2

4

10.0

8

10.5

7

9.4

8

7.8

4

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Invasion of Cyprinus carpio in Urpod Beel

The abundance or invasion of Cyprinus carpio was also surveyed at Urpod beel of

Goalpara district of Assam. The Urpod beel covers an area of about 649.38 ha and is

located between latitudes 26005'05" to 26

006'45" N and longitude 90

034'08" to

90037'45"E. Total wetland area of Goalpara district is 33221 ha that includes 151 small

wetlands (<2.25 ha). River or stream occupies 84.77% of wetlands. The other major

wetland of the district is Waterlogged (7.1%) and Lake/pond (7.0%). The average

annual rainfall in the district is 1614 mm (National Wetland Atlas, Assam). The wetland

is surrounded by the NH-37 in the south, west and north with patches of agricultural

land of villages like Agia, Shyamnagar, Gendera, Garukutia etc (Figure 1.8 and 1.9 E,

F). The eastern side of the wetland is surrounded by villages like Maijunga, Garaimari,

Khurabhasa etc. The beel is connected with another wetland called Patakata beel by a

small drain in eastern side. The Jinari river is passes by the side of the Urpod beel

before meeting the Brahmaputra river. The Jinjiram river originates from the Urpod

Beel, flows parallel to the Brahmaputra and ultimately joins near South Salmara of

Dhubri district. The beel has been included in the list of National Wetland Conservation

Programme under Govt. of India.

Fish catch data of Urpod beel

The Urpod beel is one of the potential wetland within northeastern regions of

India. In the present investigation, it has been observed that the beel contain a rich fish

diversity. The beel covers a huge area, so it is difficult to estimate the total catch of the

beel per year. The fish catch data were collected from the fisher man in different landing

site and data are compiled as percentage in Kg of different fish group from the total

catch (Table 1.4). The fish-catching intensity is higher during winter. The

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commercially important indigenous fish species of the beel are Labeo rohita, Labeo

calbasu, Labeo gonius, Catla catla, Cirrihinus mrigala, Labeo gonius, Notopterus

chitala, Aorichthys aor, Wallago attu, Channa marulius, C. punctatus, Heteropneustes

fossilis, Clarias batrachus, Notopterus notopterus etc. The exotic fish species available

in the beel are Cyprinus carpio, Ctenopharyngodon idella, and Hypothalmichthys

molitrix, Aristichthys nobilis and Clarias gariepinus. The exotic species are available

throughout the year and there has been a considerable increase of catch percent of exotic

fish in the beel. Among the exotic species common carp recorded 6.43% of total catch

in the month February (Table 1.3, Figure 1.15). The common carp has established

breeding populations in the beel. The fish catch record showed that common carp and

grass carp are more abundant other exotic fish. The mean Abundance index of four

exotic fish namely common carp, grass carp, silver carp and bighead carp in Urpod beel

are 14.85, 10.01, 8.53, and 5.74 respectively (Figure 1.16). Thus the common carp is

more abundant exotic fish in the beel.

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Table 1.4 Month wise fish catch (in percentage ) in Urpod beel during 2011

Month Common

carp

catch

Other

exotic

fish

catch

Indian

Major

Carps

Murrels

catch

Cat

fishes

catch

Feather

back

catch

Misc.

Fish

catch

January 4.59 12.11 16.56 14.2 15.18 10.05 27.31

February 6.08 7.56 16.38 19.66 13.56 6.82 30.29

March 6.14 7 15.27 19.12 12.5 2.64 37.29

April 4.11 6.25 12.36 16.32 12.07 1.03 48.1

May 3.40 6.95 15.33 14.29 13.17 3.15 44.04

June 3.35 15.88 17.56 16.39 10.36 3.22 35.04

July 2.15 16.02 22.83 13.16 14.33 4.32 27.14

August 2.68 14.91 21.34 13.11 15.2 4.11 28.91

September 3.3 12.38 24.61 11.08 16 4.23 29.54

October 4.1 13.31 22.39 13.45 14.28 5.44 27.71

November 6.08 11.3 24.62 14.26 14.37 6.2 24.2

December 7.07 9.16 25.4 16.37 16.33 7.89 18.22

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Figure 1.14. Percentage of month wise catch record of four exotic fish and other fishes

in Urpod beel during 2011.

Figure 1.15. Abundance index calculated from catch record of four exotic fish in Urpod

beel during 2011.

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Tab

le 1

.5 A

bundan

ce i

nd

ex (

AI)

of

four

exoti

c fi

sh (

Com

mon c

arp

, G

rass

car

p, S

ilver

Car

p,

Big

hea

d c

arp)

in U

rpod b

eel

duri

ng 2

011

Ex

oti

c fi

sh

Jan

Feb

M

arch

Ap

ril

May

Ju

ne

July

A

ug

Sep

t O

ct

Nov

Dec

M

ean A

I

Com

mon c

arp

12.1

2

10.2

6

10.0

0

8.6

2

12.1

5

15.2

0

16.6

5

18.1

7

20.5

2

16.7

8

12.3

4

15.4

5

14.8

5

Gra

ss c

arp

12.1

0

8.1

6

8.2

6

5.2

0

6.4

4

10.0

0

12.6

7

12.2

5

10.8

1

11.7

2

12.1

5

10.3

8

10.0

1

Sil

ver

Car

p

8.2

0

4.6

8

5.1

0

4.2

1

5.0

5

12.3

5

12.6

2

10.1

5

12.8

4

9.5

8

8.8

6

9.1

8

8.5

3

Big

hea

d c

arp

4.4

8

2.5

6

2.0

7

3.3

7

4.1

3

8.7

9

10.1

7

9.8

5

8.0

0

6.3

3

5.7

3

3.1

8

5.7

4

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Kapla beel of Barpeta district and Urpod Beels of Goalpara district of are two

impotant freshwater lakes/wetlands in Assam which have rich fish diversity and they

harbour almost all freshwater species available in the north eastern region. But this

native fish groups have been decreasing day by day. Immergence of exotic fish may be

a factor for decreasing the native fish species. Few years back the Indian Major Carps

were the most abundant fish group in the Kapla beel and Urpod beel of Assam. But now

a decreasing of total fish production has been observed in Kapla beel from the last four

years’ data. The probable cause of decreasing rate of IMC may be sharing of food and

trophic niche and high fecundity rate of exotic fish. The common carp an exotic

omnivorous fish can reproduce in confined water and this is supposed to be the main

cause of increased production rate of this fish. The species has already established

breeding populations and contributes a large percent of the exploited stock in the rivers

and beel of Assam. The introduction of a non-indigenous species may work

synergistically with other factors, such as water diversions or pollution, to alter the

population and distribution of indigenous species (Nyman, 1991). The breeding

population of common carp can negatively impact native species both directly and

indirectly by competing for food (Arthington, 1991) and habitat. Percentage of high

Abundance Index (AI) has revealed that exotic fish are now abundantly found in the

Kapla beel and Urpod beel of Assam. The exotic fish may cause changes in the

existing aquatic community through competition with native species or predation on

them, as well as through overcrowding or aggressive behaviour. Despite possessing

some attractive culture characteristics, exotic fish species generally becoming invasive

and reduce the availability of local species in natural water bodies and consequently

adversely affecting fish biodiversity and aquatic ecosystems (Lakra et al., 2008). The

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common carp has found to deteriorate the water quality of culture pond and grass carp

has found to destroy paddy field during monsoon (Choudhury et al., 2012). Invasion of

exotic species is the second most important threat to biodiversity after habitat loss.

Species invasions in freshwater lakes have been shown to cause major changes in the

distribution and abundance of endemic organisms, thereby changing the flow of energy

and nutrients (Lodge, 1993; Mills et al., 1994; Ricciardi and MacIsaac, 2000). Alien

species after established in new habitat threatens native biodiversity in that habitat by

causing changes in ecosystem. The native fish species has been decline in alarming

rates due to invasiveness of exotic fish species. A number of exotic fishes are now

available in all major rivers, reservoir and wetland of India (Kumar, 2000). The Yamuna

River and Ganges River system harboured several exotic fish species including common

carp and Nile tilapia (Singh et al., 2010a). The exotics compete with the indigenous

species for food, habitat and even prey upon them, introduce new parasites and diseases,

result in the production of hybirds and cause genetic ‘erosion’ of indigenous species

(Welcomme, 1992). There are many examples of displace of endemic fishes by exotic

fishes in lakes, and can cause changes in food web structure (Mills et al., 1994;

Ricciardi and MacIsaac, 2000). In Chiang Ek Lake of Cambodia the population of

Notopterus notopterus and other fish also have been reported to be declining due to

exotic species tilapia which constitutes up to 80% of the catch (De Iongh and Van Zon,

1993). Once such exotic species are established in a system, eradication is extremely

expensive and in many cases impossible. Hence, before releasing alien species in a

system, it is necessary to estimate the potential success and counterbalance the

ecological aftermath (Zambrano et al., 2006). In India, several exotic species viz.,

Clarias gariepinus, Ctenopharyngodon idella, C. carpio, H. nobilis, H. molitrix, O.

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mossambicus and O. niloticus niloticus were recorded from river Ganga in Uttar

Pradesh with dominancy of C. carpio (NBFGR Annual Report, 2009-2010). There are

numerous examples of the extinction of native species due to introduction of exotic

species (Lodge et al., 2000). Fleming et al. (2000) found that invasions of farm Atlantic

salmon Salmo salar in Norway have the potential for impacting on native population

productivity, disrupting local adaptations and reducing the genetic diversity of wild

salmon populations. Courtenay & Moyle (1992) called fish introductions “crimes

against biodiversity”. According to Minns and Cooley (2000), Introductions of non-

indigenous fishes can reduce diversity and modify local community dynamics in

freshwater systems. Introduced species can cause major changes in community structure

and ecosystem function (Lodge, 1993).

The present survey showed that exotic fish occurrences have been increasing

while the production other fishes are decreasing. Various anthropogenic activities are

responsible for alarming decline of fish populations in the rivers and wetlands. Over

fishing, using of chemicals and poisons, dynamiting, small mesh size fishing gears,

destruction of natural spawning and breeding grounds are main causes of decline of the

freshwater fishes. The exotic fish invasion is thought to be an important cause of

reduction of indigenous fish population. Freshwater fishes are the most imperilled

vertebrate group with a high projected extinction rate. According to Ricciardi and

MacIsaac (2000), freshwater lakes (beels) are among the ecosystems most vulnerable to

species invasion. There is a strong need for public education and awareness about the

impacts of alien species on native fauna and flora. Unless the public is aware of these

impacts, alien species will continue to be spread throughout the world. Proper

monitoring of infestation of exotic fish could save the threatened or endangered fish

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populations in wild water bodies. Detail dietary and behavioural analysis of exotic is

important before and after introduction in new environment or places. The different

exotic fish has apparently increased in recent years and the production figure of

freshwater fish fauna has changed in Assam (India). Introductions were primarily made

for aquaculture but in Assam particularly the intensity of seasonal flood in higher and

every year a large number of cultured fisheries are immerged during flood and thereby

the cultured exotic fish species invaded to natural water bodies such as beels and rivers.

The escape of the exotic fish from aquaculture to wild water may be harmful to the

indigenous aquatic fauna including fish and environment as a whole. To protect the rich

fish diversity in beels of Assam and for conservation of aquatic freshwater ecosystems,

adequate attention should be paid to check the further proliferation of invasive exotic

fish species. The present preliminary investigation has shown that in the Kapla beel of

Barpeta district of Assam the total fish production has been found decrease in the last

four years. But still the catch records detect the increased production of common carp

and other exotic fishes. The catch record and abundance index showed acceleration of

common carp infestation in the beel.

In the above account it has been observed that the Cyprinus carpio population has

been proliferating in India including Assam and the population has established in

different aquatic bodies in India. So, study of phylogeography of Cyprinus carpio

communis was aimed through study of mitochondrial gene. In addition, certain

biochemical parameters were also investigated from distinct genetic haplotypes of the

species.

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AIMS AND OBJECTIVES

In the present investigations Cyprinus carpio communis was selected and samples

were collected from different parts of the country (India) in order to identify the genetic

variations along with variations of some biochemical parameters such as proximate

compositions, amino acid profile and fatty acid profile of the varied strains of the

species. The objectives of the present study are-

1. To study the genetic divergence of Cyprinus carpio communis from different aquatic

bodies through partial sequencing of Cytochrome b gene

2. To analyse the proximate compositions along with amino acid profile and fatty acid

profile of the different haplotypes or variants identified in genetic study from different

regions of the country.