International Journal of Aquaculture, 2017, Vol.7, No.10, 71-78
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Table 2 Quality of water in captive rearing in FRP tank, normal pond and sewage fed pond and also the sewage during the study
period
Parameters
Captivity in FRP tank
Mean±SD (Range)
Normal pond
Mean±SD (Range)
Sewage-fed pond
Mean±SD (Range)
Sewage from channel
Mean±SD (Range)
Temperature (
0
C)
28.52±2.40
(26.80-30.20)
28.17±3.35
(21.59-32.21)
28.54±3.51
(21.38-32.00)
27.38±7.31
(22.20-32.55)
pH
8.01±0.11
(7.94-8.09)
7.57±0.20
(7.14-7.92)
7.51±0.22
(7.14-7.84)
7.30±0.14
(7.40-7.20)
Dissolved oxygen (mg/L)
4.78±1.56
(3.68-5.88)
7.69±1.61
(6.07-8.90)
7.89±0.85
(5.59-8.81)
2.08±0.23
(1.55-2.58)
Free carbon dioxide (mg/L)
4.00±3.52
A
4.00-12.24
8.08±7.00
A
(0.00-21.66)
13.27±5.64
A
(6.34-20.41)
51.00±4.24
(48.00-54.00)
Total hardness (mg/L)
830.40±63.75
A
(712.55-948.25)
288.63±63.14
A
(171.72-362.48)
250.50±57.57
A
(137.51-304.42)
4030.06±311.13
(3810.00-4250.00)
Total dissolved solids (mg/L)
1676.08±282.84
A
(1476.00-1867.00)
465.10±108.81
A
(295.17-575.03)
264.58±45.10
A
(190.68-360.52)
472.49±17.68
(460.03-485.07)
Biological oxygen demand (mg/L) ND
5.60±1.29
(3.59-7.53)
6.95±1.61
(3.93-9.61)
62.04±8.49
(56.00-68.10)
Phosphate-phosphorus (mg/L)
0.05±0.03
(0.03-0.09)
0.10±0.08
(0.03-0.26)
0.34±0.17
A
(0.16-0.61)
1.38±0.12
(1.29-1.46)
Ammonia-nitrogen (mg/L)
0.06±0.01
(0.05-0.06)
0.25±0.07
A
(0.13-0.28)
0.48±0.21
A
(0.29-0.96)
4.72±0.19
(4.58-4.85)
Note: FRP: Fiberglass reinforced plastic; SD: Standard deviation; ND: Not done; A: Exceeding the optimal levels (ICAR 2006)
3 Results
3.1 Water quality parameters
The water quality parameters in captive FRP tanks, normal and sewage-fed farms, and the characteristics of
sewage during the study period are presented in Table 2. The water in captive FRP tanks had high levels of free
carbon dioxide, hardness and total dissolved solids. In both normal and sewage-fed pond water, the levels of free
carbon dioxide, hardness, ammonia and total dissolved solids were higher than the respective optimal levels.
3.2 Serum IGF-1 levels in IMCs
3.2.1 Under captive condition
As shown in Table 3,
C. catla
recorded the highest serum IGF-1 (2.10±0.19 ng/ml) compared to
L. rohita
(2.04±0.08 ng/ml) and
C. mrigala
(1.90±0.09 ng/ml) under captive condition. The differences in IGF-1 levels
were, however, insignificant (P>0.05).
Table 3
Levels of serum insulin like growth factor-1 (IGF-1) in normal and sewage fed farm reared, and captive held
Labeo rohita,
Catla catla
and
Cirrhinus mrigala
.
Culture conditions
Serum insulin-like growth factor-1 (ng/ml)
Catla catla
Labeo rohita
Cirrhinus mrigala
Normal farm
1.99±0.17
2.10±0.14
1.82±0.12
A
Sewage-fed farm
2.38±0.36
a
2.06±0.03
b
1.07±0.06
abCAB
Captivity in FRP tank
2.10±0.19
2.04±0.08
1.90±0.09
B
Note: a and b: Values sharing common superscripts within the row differ significantly (P<0.05); A and B: Values sharing common
superscripts within the column differ significantly (P<0.05); Values are mean ±standard deviation of three observations.
3.2.2 Under normal pond condition in net cages
Labeo rohita
of normal pond recorded the highest serum IGF-1 level (2.10±0.14 ng/ml) followed by
C. catla
(1.99±0.17 ng/ml) and
C. mrigala
(1.82±0.12 ng/ml). The differences in IGF-1 levels (Table 3) were, however,
insignificant (P>0.05).
