Department of Animal Science and Fisheries, Delta State University, Asaba Campus, Abraka, Nigeria; Department of Forestry and Wildlife, Delta State University, Asaba Campus, Abraka, Nigeria
Nwabueze, A.A., Department of Animal Science and Fisheries, Delta State University, Asaba Campus, Abraka, Nigeria; Agbogidi, O.M., Department of Forestry and Wildlife, Delta State University, Asaba Campus, Abraka, Nigeria
The impact of sub lethal concentration of water-soluble fractions (WSFs) of crude oil on growth performance of the catfish Heterobranchus bidorsalis fingerlings (mean weight: 1.36±0.05g) was investigated under laboratory conditions during a 10 - week period of exposure in a renewal static bioassay system. The concentrations of WSFs used were 0.00 - control, 0.125, 0.50 and 1.00 ml per litre. Mortality was recorded in the 0.50 and 1.00 ml per litre concentrations. Results indicate that growth rate of fish was significantly (P≥0.05) reduced as compared with the control fish. Observations on behaviour of fish showed reduced activity especially feeding with increasing concentrations of WSFs. There were significant (P≤0.05) differences in growth and mortality rate in fish exposed to WSFs compared with the control. Investigation on the physiochemical parameter of WSFs such as temperature, dissolved oxygen (D.O), bilogical oxygen demand (B.O.D) and hydrogen ion concentration (pH) indicated a significant (P≤0.05) increase and decrease in B.O.D and D.O. respectively as compared with controls. The temperature and pH remained the same in various experimental tanks. The present study indicated that Heterobranchus bidorsalis can serve as a bio indicator of crude oil polluted water bodies. © EuroJournals Publishing, Inc. 2006.