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Ultrasonic sound effect in fish breeding:
A case
study : Dr. S.N.Biswas* ; Sri
D.Basu** ; Sri A.Roy** and Sri S. Ghosh***
Abstracts
The success of induced breeding
using pituitary gland / synthetic hormone and captive breeding
of fishes has revolutionized aquaculture all over the world.
Multiple spawning of crap fishes in also very common now a
day’s especially in West Bengal. But the quality of
seed produced in the first spawning {early season} significantly
differs with the seed produced in the mid or late season.
This has been the practical observation of the farmers in
the state of West Bengal. Seed produced in the first spawning
always do better performance in survivality, growth rate and
disease resistance. Beside this quantity of eggs spawned and
percentage of fertilized eggs observed to be less in the mid
and late spawning.
In this study, effect of ultrasonic sound on the complex process
of egg maturation, their release and rate of fertilization
were studied. It has been observed that brooders subject to
continuous emission of ultrasonic and sonic sound induces
to a significant level in the spawning behaviors which resulted complete spawning in case of natural breeding and
easy and smooth spawning without causing little stress to
the brooders during stripping. In both the cases, brooders
responded perfectly even at very lower dose, resulting enhanced
quantity of eggs and spawn.
This justifies that ultrasonic sound have a positive effect
on successful spawning and breeding of fishes.
Key words: Induced
breeding, ultrasonic sound effect, fish spawning
Introduction :
Aquaculture
in the state of West Bengal as well as in India in party with
the international scenario in the aspect has become an important
economic activity and also a potential sector for diversification
and value addition in farming. With the blend of traditional
know-how to new sciences, efficiencies have been enhanced
and the blue revolution is becoming a reality.
All this have been possible because of success of captive
breeding of fishes especially carps in the hatchery using
induced breeding technology. There are still some limitations
in the response of brooders in spawning behaviors. This in
many occasion causes death to brooders especially females
in stripping methods and in normal cases always total spawning
is not achieved, even in many cases female does not respond
at all or very less quantity of eggs and spawn are produced
and thereby hatchery / seed production center suffers.
Efforts have been made in this study to overcome this problem
in the hatchery management.
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Materials and Methods :
Two different hatcheries were selected for
this purpose.
- Carp hatchery at Freshwater Fisheries Research Station,
Kulia, Kalyani , Nadia ,West Bengal
- Magur { Clarias Batrachus}, air breathing fish seed hatchery
at Harinavi, Sonarpur, West Bengal.
In the present study 10 kg female Carp fishes (Catla, Rohu,
Mrigal, Bata and Kalbasu) and equal quantity of similar
male fishes were selected for the four sets of experiments.
The fishes were injected with pituitary gland @ 6-8 mg/kg
in case of female and 3-5 mg/kg in case of male for the
first set of experiment. In case of second and third set
of experiment, the fishes were injected @ half and one third
of the dose respectively as was applied in first set.
Similar application was also made for magur fish (Clarias
batrachus). Here, instead of pituitary gland fishes were
injected with Ovaprim@ 2ml/kg in case of female and 0.5
ml/kg in case of male for the first set of experiment. In
the third series, males were not injected with any inducing
agent. For each experimental design one control was made.
All the fishes of experimental sets (Except control) were
subjected to continuous exposure to ultrasonic sound since
they were selected from the pond and kept in the cistern,
and subsequently placed in the hatchery for breeding till
the spawning is over. One pair of Vardhman Electronics Fish Grower ?an
electronic device, cylindrical in look with one end conical—16/17
inches (L), 1.7/2 inches (D); device embedded inside the
cylinder and operated by 2 x 1.5 volts D-cell batteries?
was placed in all cases in such a manner that the fishes
were always subjected to constant emission of ultrasonic
sound.
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Results:
In case of natural breeding response to spawning was found
to be total for all the brooders and rate of fertilized eggs
were also much higher than the control.
In case of stripping readiness for spawning
for both male and female were found to be so high
that even in slight touch at vent position causes release
of eggs and milt. Without causing stress to the brooders,
complete spawning was observed .
In both the cases quantity of egg
released and percentage of fertilized eggs are much higher.
Each cases brooder positively responded to breeding irrespective
of the dose of inducing agent used.(Table-1)
In one experiment in the extreme climatic condition when the
temperature was 42° C And the male showing no sign of
maturity observe to show high maturity after those are subjected
to ultrasonic sound effect for four hours without injected
with pituitary extract.
In case of Magur, natural breeding is not
happened till date. Females are stripped to get eggs and males
are sacrificed to get milt by squeezing the whole testes as
the milt quantity is very less and for this because of heavy
stress during stripping sometimes blood come out and female
get died, which is a great loss to the hatchery.
In case of male exposed to ultrasonic sound, the testes
on opening the belly was found to be fully ripe and bigger
in shape in comparison to control and the quantity of milt
squeezed out was also found to be significantly higher than
the control. In case of female it responded easily with slight
pressure over the belly and eggs come out without causing
any injury to the ovary. No blood observed to be come out
even at the end. The spawning fertilization and spawn production
efficiency in comparison to control are shown in Table-2.
Discussion
:
Wildhaber et.al.2005 and Whiteman et.al. 2005 studied spawning
aggregations and gender identification applying ultrasonic
imaging. The present author in another experiment (Biswas
et. al. 2004) have studied positive effect on the growth of
fish spawn (towards fingerlings) using ultrasonic sound and
observed 35% higher growth rate in the spawn to fingerlings.
Prince, E. D. & Maughan, O. E. 1978 and Yeager, D.M.1982
studied the typical movement of fishes due to ultrasonic effect.
However, very scanty work on the effect of ultrasonic sound
on the fish breeding have been done.
The present study revealed
that the breeding efficiency of carp fishes increased to a
significant level using ultrasonic sound. The spawn production
level raised from 60% (in case of control) to 76.67% as studied
in Experiment 1. In all experiments the quantity of egg released
and percentage of fertilized eggs are much higher in comparison
to control irrespective of doses of pituitary gland applied.
In case of Experiment-3, 74% hatching success achieved using
very low dose of pituitary extract. Therefore, it is established
that the ultrasonic sound induces physiological process in
a much better manner as is caused by artificial injection
of pituitary gland/ synthetic hormone and it has a synergistic
effect with inducing agent on fish breeding and maturation.
In case of magur, here also the quantity of eggs spawned and
percentage of fertilization is much higher than the control.
Present experiment confirms that 78% hatching success can
be achieved using ultrasonic effect. The male fish showing
high degree of maturation while exposed to ultrasonic treatment.
The testes of the male fish of experiment –3 were observed
to be highly developed, matured with large in structure and
full of milt. The milt was thick when injected with inducing
agent but watery (normal) when not injected with any inducing
agent but were subjected to ultrasonic exposure. This shows
that ultrasonic exposure induces male magur fishes quite significantly
for normal spawning.
With the wild introduction of Clarias garipineus and
its wide spread effects on the bio diversity total ban of
breeding and culture of this fish species is urgently necessity.
Government of India as well as State Government has been putting
all endevours to stop this breeding and culture practices
and success of this experimentation hopefully shows a way
(path) towards this in encouraging Clarias garipineus (African canal cat fish) hatchery owners in adopting
breeding and seed production of Clarias batrachus.
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Table : 1 - Performance of Vardhman Electronics Fish Grower hatchery model 105/2
on CARP (IMC)
EXPERI
- MENT
|
Species
Composition
|
Qnty..of
brooders
injected
(kg)
|
Dose
of PG
(mg / kg)
|
Qnty.
of Egg
Released
(in 100 thousands)
|
%
of eggs
fertilized |
Qnty. of
Spawn
Produced
(in 100 thousands)
|
Remarks
|
Female |
Male |
Control
Expt-1
Expt-2
Expt-3
|
CARPS
(IMC)
Catla,
Rohu,
Meigal,
Bata,
Kalbasu
|
10 kg female
& 10 kg male
fishes for each
set of experiment
|
6-8
6-8
4-5
2-3 |
3-4
3-4
1-2
0.5- 1 |
12.5
18.0
17.5
16.2 |
76.00
89.00
88.50
85.00 |
7.5
13.8
13.2
12.0
|
Ex-1, Ex-2
and
Ex-3 were
Subjected to
Vardhman Electronics
F ish chaser hatchery model : 105/2 |
Table: 2 - Performance
of Vardhman Electronics Fish Grower hatchery model 105/2 on Clarias Batrachus
(Desi Magur)
EXPERI
- MENT
|
Species
Composition
|
Qnty..of
brooders
injected
(kg)
|
Dose
of PG
(mg / kg)
|
Qnty.
of Egg
Released
(in 100 thousands)
|
%
of eggs
fertilized |
Qnty. of
Spawn
Produced
(in 100 thousands)
|
Remarks
|
Female |
Male |
Control
Expt-1
Expt-2
Expt-3
|
Clarias Batrachus
(Desi Magur)
150-200g
Size each
|
1 kg
female &
1.5 kg
male for
each
experiment
|
2.0
2.0
1.0
0.6
|
0.5
0.5
0.25
Nil
|
15,000
16,500
16,000
15,500
|
78.60
89.00
85.60
84.00
|
8,500
12,000
11,500
10,000
|
Ex-1
Ex-2 and
Ex-3 were
Subjected
To
Vardhman Electronics
Fish Grower hatchery model: 105/2 |
Comment: The result shows that the Fish Grower definitely
have a positive impact on the breeding behavior of both carp
and air breathing fishes; it enhances breeding efficiency
to a significant level and proper application of the may solve
the problem of getting desired quantity of spawn without much
hazard and less injury/pain to the costly brooder. And likely
this may revolutionize fish seed hatchery once again and may
also create a boom in the ornamental fish sector.
This study shows the way to work further on this line.
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References:
1. Wildhaber M. L. et.al. 2005. Gender identification of shovelnose
sturgeon using ultrasonic and endoscope imagery and the application
of the method to the pallid sturgeon Journal of Fish Biology,
vol-67, issue-1;p-114.
2. Whiteman,E.A. Jennings, C.A., Nemeth, R.S.2005, Sex structure
and potential female fecundity in a Epinephelus guttatus spawning
aggregation: applying ultrasonic imaging Journal of Fish Biology,
vol-66; issue 4; p-983.
3. Prince, E.D.& Maughan, O.E. 1978. Ultrasonic telemetry
technique for monitoring bluegill movement. Progressive Fish-Culturist
40:90-93.
4. Yeager, D.M 1982. Ultrasonic telemetry of striped bass
x white bass hybrids in the Escambia River, Floride.Proceedings
of the annual Conference of the S.E. Association of game &
Fish wildlife Agencies, 36:62-73.
5. Biswas S.N. 2004. Study on the effect of emission of ultrasonic
sound in fish pond on the growth of fish (unpublished). |
