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Acute
toxicity of potassium permanganate to fingerlings of the
African catfish, Clarias gariepinus (Burchell, 1822)
Kori-Siakpere, Ovie
Department of Animal and Environmental Biology, Delta State
University, P. M. B. 1, Abraka, Nigeria. E-mail:
oviekori@yahoo.com, Tel: +2348033613853.
Accepted 23 April, 2008 |
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Laboratory static bioassays were conducted to determine the
96-h LC50 and the lethal levels of concentrations
of the aquaculture therapeutant, potassium permanganate
(KMnO4) on fingerlings (mean weight, 6.24 ± 0.15
g and mean length, 4.25 ± 0.07 cm) of the African catfish,
Clarias gariepinus. A total number of one hundred and
eighty (180) fingerlings of mixed sex and brood stock were
used for the toxicity bioassay. The 96-h median lethal
concentration (LC50) value obtained for treatment
of the fingerlings of the catfish C. gariepinus with
potassium permanganate was 3.02 mg/L KMnO4 with
lower and upper 95% confidence limits of 0.40 and 3.73 mg/L
KMnO4, respectively. There was very strong and
positive correlation between the variables (r = 0.96) with
93% (r2) association. Toxicity curve revealed
11.20 mg/L KMnO4 at 8.20 h as the threshold value
for the 96 h assay of potassium permanganate on fingerlings
of C. gariepinus. The 96 h LT50 for 10, 8
and 6 mg/L KMnO4 to the test fish were also
determined to be 10.40, 11.30 and 17.80 h, respectively.
Varying behavioural patterns were observed in the fish,
which included erratic swimming, loss of reflexes, total
loss of equilibrium, paleness of skin and gasping for air.
The value of water quality parameters monitored during the
exposure period did not differ significantly (P>0.05) within
the various concentrations of the therapeutant (KMnO4)
as well as with the control. However, pH and total
alkalinity tended to increase with increasing concentration
of the toxicant.
Key words:
Potassium permanganate, acute toxicity, LC50, LT50,
behaviour, Clarias gariepinus, Nigeria. |
