EFFECTS OF DIFFERENT FEEDING REGIME,
WEANING PERIOD AND STOCKING DENSITY
ON THE SURVIVAL AND GROWTH
OF STINGING CATFISH FRY
(Heteropneustes fossilis, Bloch)
THEERAWAT SAMPHAWAMANA
st 105453
1
CHAPTER 1
INTRODUCTION

Distribute in South-Asia
and South-east Asia.

Good taste

High price

High nutritive
Heteropneustes fossilis, (Bloch)
Yadav, 1999
2
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
3
Reported studies

Feeding regime
Live-feeds are essential for carnivorous fish at the first
stage (Dabrowski and Culver, 1991).

Weaning period
Co-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 density
Over-stocking has consequently slow growth and low
survival (Shepherd and Bromage, 1992)
.
Experimental
design
Nursing fry with different live-feeds
Experiment 1
Select the best live-feed
Weaning fish fry onto artificial diets
with different acclimation schedules
Experiment 2
Select the best weaning procedure
Rearing weaned fry with different
stocking densities
Experiment 3
Determine the proper stocking density
Recommend the suitable
nursing protocols
5
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.
6
Design of Experiment 1
Trt
Feed
1A
Rotifer
2A
Artemia
3A
Moina
1st week: small-size Moina
After 1st week: ungraded Moina
4A
1st week: Rotifer
2nd week: Artemia
3rd week: Moina
SD
8 fry/L
8 fry/L
8 fry/L
REP
4
4
4
8 fry/L
4
7
Rotifer: 0.15+ 0.03 mm
Artemia : 0.5+ 0.06 mm
Small-size Moina : 0.36+ 0.04 mm
Ungraded Moina : 0.84+ 0.15 mm
8
Live-feeds
Rotifer
Small-size Moina
Artemia
Ungraded Moina
9
Treatment3:Moina were graded by sieving through 400
micron seine net during the first week.
400 micron
69 micron
10
Fish sample (2 day-old)
11
Maintenance of experiment tanks
12
Length and weight measurement
13
Fish mouth measurement
14
Results of experiment 1
Parameters
1A
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
15
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
This might have resulted from the higher nutritive value.
Source of data: Watanabe (1994)
16
Size of fish mouth and live-feeds
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
Type of
live-feeds
Rotifer
Artemia
Smallsize
Moina
Ungraded
-Moina
Size (mm) 0.16+ 0.03 0.5+ 0.06 0.36+ 0.04 0.84+ 0.15
This might have resulted from the appropriate size.
17
Comparison between size of fry mouth and
live-feeds (micron)
fish mouth
2000
1800
1600
1400
1200
1000
800
600
400
200
0
rotifer
artemia
small-size moina
ungraded-moina
2 days
7 days
14 days
21 days
Appropriate size of live-feeds for larval feeding should be
approximately 50% of fish mouth size (Shirota, 1970)
18
Comparison between size of fry mouth and
live-feeds (micron)
fish mouth
900
800
700
600
500
400
300
200
100
0
rotifer
artemia
small-size moina
ungraded-moina
2 days
Fry should be fed with small-size Moina in the first week due to the appropriate size.
19
Comparison between size of fry mouth and
live-feeds (micron)
1200
fish mouth
1000
rotifer
800
artemia
600
400
small-size moina
200
ungraded-moina
0
7 days
Fry should be fed with small-size Moina in the first week due to the appropriate size.
20
Comparison between size of fry mouth and
live-feeds (micron)
fish mouth
1600
1400
1200
1000
800
600
400
200
0
rotifer
artemia
small-size moina
ungraded-moina
14 days
21
Comparison between size of fry mouth and
live-feeds (micron)
fish mouth
2000
1800
1600
1400
1200
1000
800
600
400
200
0
rotifer
artemia
small-size moina
ungraded-moina
21 days
22
Experimental
design
Nursing fry with different live-feeds
Experiment 1
Moina
Select the best live-feed
Weaning fish fry onto artificial diets
with different acclimation schedules
Experiment 2
Select the best weaning procedure
Rearing weaned fry with different
stocking densities
Experiment 3
Determine the proper stocking density
Recommend the suitable
nursing protocols
23
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.
24
Design of experiment 2
Live
feed
(time/day)
Dry
feed
(time/day)
Live
control
Dry
control
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
25
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
Thailuxe company
composition of dry-feeds used in experiments
26
Artificial diets
27
Maintenance and measurement
28
Results of experiment 2
parameters
Live
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
29
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
Experimental
design
Nursing fry with different live-feeds
Experiment 1
Moina
Weaning fish fry onto artificial diets
with different acclimation schedules
Experiment 2
15
days
Select
the weaning
best weaningschedules
procedure
(change every 3 day)
Rearing weaned fry with different
stocking densities
Experiment 3
Determine the proper stocking density
Recommend the suitable
nursing protocols
31
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
32
Design of experiment 3
Stocking density
Treatment
(fry/L)
1C
4
2C
3C
4C
5C
6
8
10
12
Feed
replication
No.2
No.2
No.2
No.2
No.2
3
3
3
3
3
Dry feed:Thailuxe company
33
Experiment 3
34
Length and weight measurement
35
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
36
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
Comparison between water quality parameters
during experiment periods and optimum level
parameters 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
Experimental
design
Nursing fry with different live-feeds
Experiment 1
Moina
Weaning fish fry onto artificial diets
with different acclimation schedules
Experiment 2
15 day weaning schedules
Rearing weaned fry with different
stocking densities
Experiment 3
8 fry / L
Determine the proper stocking density
Recommend the suitable
nursing protocols
39
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).
40
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.
41
Thank you
42