Objective:
Cadmium (Cd) is one of the most hazardous heavy metals in aquatic environments and cou
ld threaten aquatic organisms including fish.
The present study was carried out to know the protective effects of calcium (Ca) and selenium (Se) in reducing the Cd bioaccu
mulation in
selected
tissues
of
fresh water
fish,
Oreochromis mossambicus
.
Method
s:
The
fresh water
fish,
Oreochromis mossambicus (Tilapia)
was brought from the local ponds and were allowed for acclimatization to the
laboratory conditions.
After acclimatization, fish were exposed to sublethal
concentration of Cd (1/10
th
of LC
50
Result
s:
Cd concentrati
on levels significantly (P
<0.05)
increased in the test tissues with
increased
period of exposure. Maximum Cd accumulation
was found in 30d Cd
-exposed
fish kidney tissue (22.611±0.676 μg
/gm wet wt. of the tissue). However
, after supplementing with Ca and/or
Se, there
was
a significant
reversal in the
levels of Cd concentration
in all the test tissues
. Maximum reduction was observed under Ca alone supplementation.
/48h,
i.e.
, 5 ppm
) for 7, 15 and 3
0 d
(d) period. 15d Cd
-exposed
fish were divided into three groups. The first group of fish were
subjected to Ca (
1 ppm
) supplementation, second
group
received only Se (
1 ppm
) supplement and third
group of fish were supplemented with
the combination of both Ca and Se at the above said doses
and observed for 7, 15 and 30d time periods. After specific time intervals, liver, kidney, gill and intestine
tissues were isolated and used for Cd
bioaccumulation studies
.
Conclusio
n
:
The
present study
clearly
reveals that individual supplementation of Ca tends to de
toxify the Cd body burden in the test tissues than
the other modes of supplementation.