D.O. Odedeyi , K.E. Odo

Department of Animal and Environmental Biology, Faculty of Science, Adekunle Ajasin University, Akungba-Akoko, Ondo State, Nigeria
Author    Correspondence author
International Journal of Aquaculture, 2017, Vol. 7, No. 9   doi: 10.5376/ija.2017.07.0009
Received: 22 May, 2017    Accepted: 15 Jun., 2017    Published: 30 Jun., 2017

This is an open access article published under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Odedeyi D.O., and Odo K.E., 2017, Acute toxicity and haematology of Clarias gariepinus exposed to selenium, International Journal of Aquaculture, 7(9): 64-70 (doi: 10.5376/ija.2017.07.0009)

The acute toxicity and haematological effect of selenium was investigated on Clarias gariepinus juvenile. 180 healthy C. gariepinus juveniles with mean weight of 7.4 ± 0.64 g and length of 11.2 ± 0.88 cm were exposed to different concentrations (0, 2, 3, 4, 5 and 6 mg/l) of selenium under a static method of bioassay for 96 hours. The mortality rate of the experimental fish increased with increase in concentration of the selenium. The 24, 48, 72 and 96 hours LC₅₀ were estimated to be 8.49, 6.36, 4.80 and 3.39 mg/l respectively which was analysed using probit method. The dissolved oxygen of the culture media was significantly lower p < 0.05 in the treatments when compared to the control. The blood parameters: Pack Cell Volume (PCV), Red Blood Cell (RBC), White Blood Cell (WBC) and Haemoglobin (Hb) showed decrease from lowest concentration (2 mg/l) to highest concentration (6 mg/l). There were variations in the derived haematological indices of mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH) and mean corpuscular haemoglobin concentration (MCHC). In conclusion, it was observed that selenium at high concentration is toxic and caused a successive population decline of C. gariepinus. Fish farmers should as much as possible locate farms from likely source of toxicants.

Selenium; Clarias gariepinus; LC50; Haematology