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Transcript of 1 EFFECTS OF DIFFERENT FEEDING REGIME, WEANING PERIOD AND STOCKING DENSITY ON THE SURVIVAL AND...
![Page 1: 1 EFFECTS OF DIFFERENT FEEDING REGIME, WEANING PERIOD AND STOCKING DENSITY ON THE SURVIVAL AND GROWTH OF STINGING CATFISH FRY (Heteropneustes fossilis,](https://reader036.fdocuments.us/reader036/viewer/2022062301/56649ee45503460f94bf3a3f/html5/thumbnails/1.jpg)
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EFFECTS OF DIFFERENT FEEDING REGI EFFECTS OF DIFFERENT FEEDING REGIMMEE,,
WEANING PERIOD AND STOCKING DENS WEANING PERIOD AND STOCKING DENSITITYY
ON ON THE THE SURVIVAL AND GROWTH SURVIVAL AND GROWTH OF OF STINGINGSTINGING CATFISH FRY CATFISH FRY
(( Heteropneustes fos Heteropneustes fossisilislis , Bloch) , Bloch)
THEERAWAT SAMPHAWAMANAst 105453
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CHAPTER 1INTRODUCTION
Distribute in South-Asia and South-east Asia.
Good taste
High price
High nutritive Heteropneustes fossilis, (Bloch)
Yadav, 1999
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Problem statement
Major constraints of H. fossilis larvae rearing is
the high rate of mortality.
How to improve the survival?
1. Feeding regime
2. Weaning period
3. Stocking density
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Reported studies Feeding regime
Live-feeds are essential for carnivorous fish at the first stage (Dabrowski and Culver, 1991).
Weaning periodCo-feeding live-feed and artificial diets provided higher growth and survival than feeding either live-feeds or micro-diets alone (Giri et al., 2002).
Stocking densityOver-stocking has consequently slow growth and low survival (Shepherd and Bromage, 1992)
.
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Experimental
design
Determine the proper stocking density
Rearing weaned fry with different stocking densities
Select the best weaning procedure
Weaning fish fry onto artificial diets with different acclimation schedules
Select the best live-feed
Experiment 1
Nursing fry with different live-feeds
Recommend the suitable nursing protocols
Experiment 2
Experiment 3
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Experiment 1
To evaluate the effect of different live feeds on the growth and survival of H. fossilis fry at the first stage.
Null hypothesis: There is no effect of different live feeds on the survival and growth of H. fossilis fry.
Experiment period: 21 days
4 treatments and 4 replications.
Two days-old fry were reared with 3 different types of live feeds.
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Design of Experiment 1
Trt Feed SD REP
1A Rotifer 8 fry/L 4
2A Artemia 8 fry/L 4
3A Moina
1st week: small-size Moina
After 1st week: ungraded Moina
8 fry/L 4
4A 1st week: Rotifer
2nd week: Artemia
3rd week: Moina
8 fry/L 4
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Artemia : 0.5+ 0.06 mm
Small-size Moina : 0.36+ 0.04 mmRotifer: 0.15+ 0.03 mm
Ungraded Moina : 0.84+ 0.15 mm
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Live-feeds
Rotifer
Ungraded MoinaArtemia
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Treatment3:Moina were graded by sieving through 400 micron seine net during the first week.
400 micron
69 micron
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Fish sample (2 day-old)
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Maintenance of experiment tanks
12
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Length and weight measurement
13
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Fish mouth measurement
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Results of experiment 1
Parameters1A
Fed Rotifer
2A
Fed Artemia
3A
Fed Moina
4A
Combination
Mean final weight
FMW (mg)
27.47c
± 7
51.27b
± 14
81.78a
± 29
63.54b
± 21
Daily weight gain
DWG (mg/day)
1.27c
± 1.3
2.6b
± 2.6
3.61a
± 3.6
2.93ab
± 3.0
Specific growth rate
SGR (%)
26.95c
± 0.4
30.0b
± 1.0
31.63a
± 1.0
30.65ab
± 0.5
Mean final length
FML (%)
13.41c
± 0.12
18.09b
± 0.23
20.03a
± 0.3
19.3ab
± 7
Survival (%)63.25b
± 3.3
84.06a
± 3.1
86.87a
± 1.8
83.81a
± 3.0
Fry fed Moina showed the best growth
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Supporting literature
species Protein % Fibre % Fat % Ash %
Moina 71.6 7.4 20.6 11.8
Artemia 61.6 2.7 19.4 10.1
Rotifer 66.7 2.7 24.1 4.3
Source of data: Watanabe (1994)
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This might have resulted from the higher nutritive value.
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Size of fish mouth and live-feeds
Type of live-feeds
Rotifer ArtemiaSmall-size
Moina
Ungraded-Moina
Size (mm) 0.16+ 0.03
0.5+ 0.06 0.36+ 0.04
0.84+ 0.15
Age of fry 2 days 7 days 14 days 21 days
Size (mm) 0.66+ 0.02 1.13+ 0.09 1.44+ 0.2 1.72+ 0.03
This might have resulted from the appropriate size.
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Comparison between size of fry mouth and live-feeds (micron)
0200400600800
100012001400160018002000
2 days 7 days 14 days 21 days
fish mouth
rotifer
artemia
small-size moina
ungraded-moina
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Appropriate size of live-feeds for larval feeding should be approximately 50% of fish mouth size (Shirota, 1970)
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Comparison between size of fry mouth and live-feeds (micron)
0100200300400500600700800900
2 days
fish mouth
rotifer
artemia
small-size moina
ungraded-moina
19
Fry should be fed with small-size Moina in the first week due to the appropriate size.
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Comparison between size of fry mouth and live-feeds (micron)
20
0
200
400
600
800
1000
1200
7 days
fish mouth
rotifer
artemia
small-size moina
ungraded-moina
Fry should be fed with small-size Moina in the first week due to the appropriate size.
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Comparison between size of fry mouth and live-feeds (micron)
21
0200400600800
1000120014001600
14 days
fish mouth
rotifer
artemia
small-size moina
ungraded-moina
![Page 22: 1 EFFECTS OF DIFFERENT FEEDING REGIME, WEANING PERIOD AND STOCKING DENSITY ON THE SURVIVAL AND GROWTH OF STINGING CATFISH FRY (Heteropneustes fossilis,](https://reader036.fdocuments.us/reader036/viewer/2022062301/56649ee45503460f94bf3a3f/html5/thumbnails/22.jpg)
Comparison between size of fry mouth and live-feeds (micron)
22
0200400600800
100012001400160018002000
21 days
fish mouth
rotifer
artemia
small-size moina
ungraded-moina
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Experimental
design
Determine the proper stocking density
Rearing weaned fry with different stocking densities
Select the best weaning procedure
Weaning fish fry onto artificial diets with different acclimation schedules
Select the best live-feed
Experiment 1
Nursing fry with different live-feeds
Recommend the suitable nursing protocols
Experiment 2
Experiment 3
Moina
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Experiment 2
To investigate the effect of weaning periods in terms of different acclimation schedules weaning onto artificial diets.
Null hypothesis: There is no effect of different weaning periods on the survival and growth of H. fossilis fry.
6 treatments and 4 replications
Experiment period: 30 days
Weaning periods: 0, 5, 10, 15, and 20 days were investigated.
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Design of experiment 2
Live feed
(time/day)
Dry feed
(time/day)
Livecontrol
Drycontrol
change every 1 day
change every 2 day
change every 3 day
change every 4 day
5 0 - - 1 2 3 4
4 1 - - 1 2 3 4
3 2 - - 1 2 3 4
2 3 - - 1 2 3 4
1 4 - - 1 2 3 4
0 5 - - 25 20 15 10
Total acclimatization weaning period (day)
0 0 5 10 15 20
Total experiment duration (day)
30 30 30 30 30 30
- : continuous feeding of live feed or dry feed
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Artificial diets
Two types of artificial feeds were used
Feed No.1 No.2
Type
Particle size
Moisture (%)
Crude protein (%)
Crude Lipid (%)
Crude Fibre (%)
Ash (%)
Powder feed
0.3-0.8 mm
7.39
38.81
5.35
2.72
14.26
Sinking pellet feed
1.0–1.7 mm
8.09
38.78
5.49
2.56
14.38
composition of dry-feeds used in experiments
Thailuxe company
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Artificial diets
27
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Maintenance and measurement
28
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Results of experiment 2
parametersLive
control
Dry
control
change
every
1 day
change
every
2 day
change
every
3 day
change
every
4 day
Mean final weight (mg)
162.5a
± 15
62.5d
± 5
92.5c
± 5
127.5b
± 17
150a
± 16
155a
± 19
Daily weight gain (mg/day)
5.36a
± 0.4
2.02d
± 0.2
3.02c
± 0.2
4.19b
± 0.5
4.94a
± 0.5
5.11a
± 0.6
Specific growth rate(%)
16.9a
± 0.3
13.7d
± 0.3
15.1c
± 0.15
16.1b
± 0.4
16.7a
± 0.3
16.8a
± 0.4
Mean final length (mm)
28.6a
± 0.9
21.8d
± 0.2
24.2c
± 0.3
26.2b
± 0.9
28a
± 1.1
28.9a
± 1.7
Survival
(%)
84.56a
± 3.2
1.16d
± 0.3
10.5c
± 2.2
65.25b
± 4.0
81.37a
± 2.1
82.87a
± 2.3
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Discussion
H. fossilis fry could not be activated to artificial feed by directly feeding them with dry feed.
H. fossilis fry can be weaned from live-feed to artificial feed by introducing dry feed every 3 days intervals (15 days weaning intervals).
The selection of 3 days intervals would be economically advantageous as it assist to reduce live-feed requirement.
30
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Experimental
design
Determine the proper stocking density
Rearing weaned fry with different stocking densities
Select the best weaning procedure
Weaning fish fry onto artificial diets with different acclimation schedules
MoinaExperiment 1
Nursing fry with different live-feeds
Recommend the suitable nursing protocols
Experiment 2
Experiment 3
15 days weaning schedules(change every 3 day)
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Experiment 3
To determine the optimum rearing density.
Null hypothesis: There is no effect of different stocking densities on the survival and growth of H. fossilis fry.
Fry were fed with sinking pellet feed No.2
Set up with 5 treatments, 3 replications
Experiment period: 60 days
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Design of experiment 3
Treatment Stocking density
(fry/L)Feed replication
1C
2C
3C
4C
5C
4
6
8
10
12
No.2
No.2
No.2
No.2
No.2
3
3
3
3
3
Dry feed:Thailuxe company
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Experiment 3
34
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Length and weight measurement
35
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Results of experiment 3
parameters 4 fry/L 6 fry/L 8 fry/L 10 fry/L 12 fry/L
Mean final weight(mg)
1,238a
± 31
1,130a
± 26
1,106a
± 34
1,088b
± 42
970b
± 33
Daily weight gain(mg/day)
18.04a
± 0.3
16.33b
± 0.3
15.93c
± 0.3
15.64c
± 0.4
13.66c
± 0.3
Specific growth rate(%)
11.8a
± 0.05
11.7a
± 0.11
11.7a
± 0.22
11.6a
± 0.29
11.5b
± 0.22
MFL
(cm)
6.08a
± 0.52
5.87a
± 0.46
5.8a
± 0.63
5.73b
± 0.78
5.37c
± 0.63
Survival
(%)
39.6a
± 1.8
40.9a
± 4.3
38.5a
± 3.2
33.3b
± 1.4
30.6b
± 2.1
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Discussion Optimum stocking density of H. fossilis is
8 fry/L.
Over-stocking has negative impact on growth and survival rate due to the competition for space. This might be due to stress.
Low temperature might have caused low
survival in all treatments.
37
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Comparison between water quality parameters during experiment
periods and optimum levelparameters Experiment 1 Experiment 2 Experiment 3
optimum level
DO 5.04-7.95 5.7-7.44 5.86-7.18 > 5
Temp 25.2-31.9 26.0-30.5 22.0-28.9 25-30
pH 7.3-7.94 7.3-7.68 7.3-7.89 6.5-8.5
TAN 0.00-0.17 0.00-0.18 0.00-0.09 < 0.1
NO2 0.00-0.03 0.00-0.06 0.00-0.04 < 0.1
Source of optimum level data: (Boyd,1990) 38
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Experimental
design
Determine the proper stocking density
Rearing weaned fry with different stocking densities
15 day weaning schedules
Weaning fish fry onto artificial diets with different acclimation schedules
Moina
Experiment 1
Nursing fry with different live-feeds
Recommend the suitable nursing protocols
Experiment 2
Experiment 3
8 fry / L
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Conclusions
Hypothesis 1: Moina is the most suitable live-feed for H. fossilis larval rearing at the first 3 weeks.
Hypothesis 2: H. fossilis fry can be completely weaned from Moina to artificial-feeds within 15 days with 3 gradually acclimatization per each live-feed to artificial-feeds combination.
Hypothesis 3: 8 fry/L is optimum stocking density of post-weaned H. fossilis fry rearing until achieving the fingerling size (3 month-old).
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Recommendation
Comparison between H. fossilis fed small-size Moina and ungraded Moina at the first week should be done to evaluate the effect of different size, in term of growth and survival.
The development of suitable growth-out system for achieving the marketable size should be conducted.
During the experiment periods, affected should be paid for maintain optimum environment parameters, such as water temperature.
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Thank you
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