Download B Sc Zoology Complementary Practical Semester IV Catla catla

B Sc Zoology Complementary Practical
Semester IV
Catla catla
 Catla catla also known as Indian carp is the only member of the genus Catla, of the carp
family Cyprinidae.
 Body short and deep, somewhat laterally compressed, its depth more than head length.
 Head very large, its depth exceeding half the head length.
 Body with conspicuously large cycloid scales, head devoid of scales; snout bluntly
rounded.
 Eyes large and visible from underside of the head
 It is a fish with a large protruding lower jaw.
 Upper lip absent, lower lip very thick; no barbells
 Dorsal fin inserted slightly in advance of pelvic fins, with 14 to 16 branched rays, anal fin
short; pectoral fins long extending to pelvic fins; caudal fin forked; lateral line with 40 to
43 scales.
 It reaches a maximum length of 1.83 m (6.0 ft) and a weight of about 110 kg (240 lb).
 Catla has large, greyish scale on dorsal side and whitish on belly.
 Its higher growth rate and compatibility with other major carps, specific surface feeding
habit, and consumer preference have increased its popularity in carp polyculture systems
among the fish farmers.
 At present, Catla forms an integral component species, both in three-species polyculture
with Rohu (Labeo rohita) and Mrigal (Cirrhinus mrigala), and six-species composite
carp culture, which adds common carp (Cyprinus carpio), grass carp (Ctenopharyngodon
idellus) and silver carp (Hypophthalmichthys molitrix) to the species mix.
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Labeo rohita
 Rohu (Labeo rohita) is the most important among the three Indian major carp species
used in carp polyculture systems.
 Body bilaterally symmetrical, moderately elongate, its dorsal profile more arched than
the ventral profile.
 Body with cycloid scales, head without scale
 Snout fairly depressed, projecting beyond mouth, without lateral lobe.
 Eyes dorso-lateral in position, not visible from outside of head
 Mouth small and inferior; lips thick and fringed with a distinct inner fold to each lip,
lobate or entire; a pair of small maxillary barbels concealed in lateral groove
 No teeth on jaws; upper jaw not extending to front edge of eye
 Dorsal fin inserted midway between snout tip and base of caudal fin
 Pectoral and pelvic fins laterally inserted
 Caudal fin deeply forked
 Lateral line scales 40 to 44
 Colour bluish on back, silvery on flanks and belly.
 The compatibility of rohu with other carps like catla (Catla catla) and mrigal (Cirrhinus
mrigala) made it an ideal candidate for carp polyculture systems.
 It is a fast growing species and attains about 35-45 cm total length and 700-800 g in one
year under normal culture conditions.
 Generally, in polyculture, its growth rate is higher than that of mrigal but lower than
catla.
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Cirrhinus mrigala
 Mrigal (Cirrhinus mrigala), a carp endemic to Indo-Gangetic riverine systems.
 It is one of the three Indian major carp species cultivated widely in Southeast Asian
countries.
 This species has long been important in polyculture with other native species.
 Body bilaterally symmetrical and streamlined, its depth about equal to length of head.
 Body with cycloid scales, head without scales.
 Snout blunt, often with pores; mouth broad, transverse; upper lip entire and not
continuous with lower lip, lower lip most indistinct.
 Single pair of short rostral barbells
 Dorsal fin as high as body with 12 or 13 branched rays; last unbranched ray of dorsal fin
non-osseous and non-serrated;
 Pectoral fins shorter than head; Caudal fin deeply forked; anal fin not extending to caudal
fin
 Lateral line with 40-45 scales: Dorsal fin greyish; pectoral, pelvic and anal fins orangetipped.
 Mrigal is eurythermal, appearing to tolerate a minimum temperature of 14 ºC.
 In culture, the species normally attains 600-700 g in the first year, depending on stocking
density and management practices.
 Maturity is attained in two years in captivity. Mrigal is a highly fecund fish.
 Mrigal is normally cultured along with the other two Indian major carps - catla (Catla
catla) and rohu (Labeo rohita). It is also cultured in composite carp culture systems that
include the three Indian major carps as well as two Chinese carps - silver carp
(Hypophthalmichthys molitrix) and grass carp (Ctenopharyngodon idella) - and common
carp (Cyprinus carpio).
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Ctenopharyngodon idellus
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Body elongated and cylindrical, round abdomen, compressed at the rear
Length of caudal peduncle is larger than the width
Head medium; terminal mouth and arch-shaped
Upper jaw extends slightly over lower jaw, its rear can reach below eye
Scales large and cycloid; extreme 39-46 scales in lateral line, lateral line extends to
caudal peduncle.
Body color: greenish yellow laterally, dorsal portion dark brown; greyish white in
abdomen.
It is a basically herbivorous fish that naturally feeds on certain aquatic weeds. However,
the fry/larvae feed on zooplankton.
Under culture conditions, grass carp can well accept artificial feed such as the byproducts from grain processing, vegetable oil extraction meals, and pelleted feeds, in
addition to aquatic weeds and terrestrial grasses.
Grass carp normally dwell in mid-lower layer of the water column. Comparatively, it
prefers clear water and can move swiftly.
Normally, grass carp reach 0.5-1.5 kg in 8-10 months.
In India, grass carp are cultured as an important species in pond-based composite systems
consisting mainly of Indian major carps and Chinese carps.
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Cyprinus carpio
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Body elongated and somewhat compressed.
Lips thick.
Two pairs of barbels at angle of mouth, shorter ones on the upper lip.
Lateral line with 32 to 38 scales.
Colour 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.
Carp are mainly bottom dwellers but search for food in the middle and upper layers of the
water body.
Best growth is obtained when water temperature ranges between 23 °C and 30 °C.
The fish can survive cold winter periods. Salinity up to about 5‰ is tolerated.
The optimal pH range is 6.5-9.0.
The species can survive low oxygen concentration (0.3-0.5 mg/litre) as well as
supersaturation.
Carp are omnivorous, with a high tendency towards the consumption of animal food,
such as water insects, larvae of insects, worms, molluscs, and zooplankton.
The daily growth of carp can be 2 to 4 percent of body weigh.
Carps can reach 0.6 to 1.0 kg body weight within one season in the polycultural fish
ponds of subtropical/tropical areas.
Common carp can be produced in extensive, natural food and supplementary feed-based
monocultural production systems, in stagnant water ponds. Artificial feed-based intensive
monocultural production can be carried out in cages, irrigation reservoirs, and running
water ponds and tanks, or in recirculation systems.
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Etroplus suratensis
 Etroplus suratensis is distributed in the coastal regions of peninsular India and Sri Lanka.
 It is also known as the pearlspot or karimeen in Malayalam.
 In India, the wild populations have been recorded from the states of Kerala and Tamil
Nadu.
 There are also populations in Goa, Andhra Pradesh, Orissa and West Bengal.
 It can be a perfect fish for Pisciculture.
 The species has now been introduced to dam reservoirs in the mountains and lakes and
culture ponds.
 Etroplus suratensis is a euryhaline species that inhabits mainly brackish water and river
mouths.
 It is an oval-shaped cichlid with a short snout, small mouth not extending past the front
margin of the eye with a greyish-green colouration on the flanks, with 6 to 8 dark bars
and a dark spot at base of the pectoral fin.
 Most scales on the sides are with a pearly spot.
 Macrophytic fragments form the most important component of its diet along
with molluscs, although detritus, diatoms, and animal matter are also ingested.
 Adults engage in altruistic multiple parental care where several adults care for a single
brood that presumably were spawned by only two of the adults
 It commonly reaches 20 centimetres (7.9 in) in length, and the maximum length is twice
that.
 In 2010 Kerala declared Karimeen as the official fish of Kerala state.
 The Year 2010-'11 was observed as 'The Year of the Karimeen"
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Tilapia mossambicus
 Body compressed
 Caudal peduncle depth equal to length; Scales cycloid.
 Breeding males with enlarged jaw and blue upper lip, body blue or black with lower
section of head white, red margins on dorsal and caudal fins
 Females and non-breeding males silvery with two to five black mid-lateral blotches and
three to four more dorsal blotches
 Lateral line interrupted.
 Dorsal fin with 16 - 17 spines and 11 to 15 soft rays. Anal fin with 3 spines and 10-11
rays. Caudal fin truncated.
 It is an omnivorous grazer that feeds on phytoplankton, periphyton, aquatic plants, small
invertebrates, benthic fauna, detritus and bacterial films associated with detritus.
 Sexual maturity in ponds is reached at an age of 5-6 months.
 Spawning begins when the water temperature reaches 24 °C.
 The breeding process starts when the male establishes a territory, digs a craterlike
spawning nest and guards his territory. The ripe female spawns in the nest, and
immediately after fertilization by the male, collects the eggs into her mouth and moves
off.
 The female incubates the eggs in her mouth and broods the fry after hatching until the
yolk sac is absorbed.
 Incubating and brooding is accomplished in 1 to 2 weeks, depending on temperature.
After fry are released, they may swim back into her mouth if danger threatens.
 The male remains in his territory, guarding the nest, and is able to fertilize eggs from a
succession of females.
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