Breeding of Climbing perch (Anabas testudineus)
Climbing perch
(Anabas testudineus), which is a highly demanded food fish. It
is an important air breathing fish, which can be considered for culture in
the areas with low dissolved oxygen. It is also popular for their lean meat,
which contain easily digestible protein and fat of very low melting point and
many essential amino acids making them ideal food. In India there are two
species of anabas available i.e. A. testudineus and A. oligolepis. The
fish having less deep body, lower pectoral and shorter snout is A.
oligolepis with 46 chromosomes numbers and the fish with more deep body,
shorter pectorals and longer snout is A. testudineus with 48 chromosomes
numbers. Now anabas is a threatened species due to over exploitation and
conservation measure is very much needed. Induce mass breeding and culture of
this species may be ensuring to sum the fish in nature. This fish has a
tendency to walk away from the pond during rains. It can be cultured singly or
in combination with magur (Clarius batrachus) and singhi (H. fossilis).
It can also be grown in combination with carp fingerlings of over 10 cm sizes.
This practice can be employed in order to utilize the insect fauna as well as
in respect of the role of fish as a biological check on small insects in water.
The adults of A. testudineus are solitary and
aggressive. It can gain weight up to 52gm in one year. Maturity occurs at the
age of one when the fishes reach a size of 10-12cm in total length. The sexual
dimorphism in A. testudineus is more apparent during breeding season. The
mature male acquires a reddish hue on the body, particularly on the pectoral
and ventral fins. The female shows only a faint reddish colour. Further in the
male a distinct diamond shaped black spot appears in the caudal peduncle. In
the female this black spot is oblong and somewhat diffused. Moreover, the
female is contrast to the male, has a prominently bulging abdomen. The ventral
distance between the bases of the two pectoral fins in the female is
significantly greater than the male. In the breeding season, the female
exhibits a prominent bulge at the vent, resembling the genital papillae while
in the male this structure is absent. Mature male oozed out white milt and
mature female oozed out ova even at a gentle pressure at the abdomen during
breeding season.
In nature the eggs are scattered in open water
at the onset of the rains without any nest. The male wraps itself in the female
body, fertilizing the eggs as they are laid. Each time 200 colorless eggs are
released until about 5000 numbers are laid. The fecundity varies from
5000-35000 numbers. The eggs rise to the surface and float. The eggs hatch in
24 hrs and the fry are about 2-3 mm long. They are free swimming within two
days of hatching.In case of artificial breeding with pituitary or synthetic
hormone, a single dose of injection for both the male and female spawning
actively and courtship behavior starts after 6 hrs of injection. The water
temperature to be maintained at 280 C + 10C. Fertilized
eggs float in the surface of water. It takes 18-19 hrs for hatching after
spawning and newly hatches larvae measures 1.9-2.0 mm in length without any
movement. Yolk sac completely absorbs on third day after hatching and settles
at the bottom. Egg custard, plankton and Artemia are supplied as artificial feed
for those fries up to 20-25 days. The survivability varies from 70-75%
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