Comparative study of physico-chemical parameters and microbial load of aqua media of different receptacles used in culturing Clarias gariepinus

Abstract

The physico-chemical parameters cum microbial loads of water from earthen, concrete and collapsible plastic tank, tagged A, B and C respectively, were used to culture Clarias gariepinus at the Integrated Organic Fish Farm of the Department of Fisheries and Aquaculture, Nnamdi Azikiwe University, Awka, Anambra State, Nigeria, which lasted for sixteen (16) weeks. Water samples were collected aseptically every week throughout the duration of the research. The mean values of physico-chemical parameters using analysis of variance (ANOVA), showed that there was no significant difference (p>0.05) in treatments A, B and C. The results showed that earthen pond recorded the highest in Biological Dissolved Oxygen (BOD) 3.67±0.417 mg/L, Sulphate 4.55±0.016 mg/L, Nitrate 3.12±0.023mg/L and Magnesium 1.28±0.042 mg/L, followed by B and C, while concrete pond recorded highest mean values in temperature 28.17±0.234°C, pH 7.10±0.252, alkalinity 31.17±0.189 mg/L, calcium 0.53±0.O27 mg/L, and potassium 11.68±0.016 mg/L followed by A and C. and collapsible plastic tank recorded highest mean values in dissolved oxygen DO 9.83±0.240 mg/L, and transparency 60.67±0.667 cm/L. The physico-chemical parameters were all within the accepted standard range by the World Health Organization (WHO) and Federal Emergency Protection Agency for culturing fish. The Least Significant Difference (LSD) showed that there were significant differences (p<0.05) between the bacteria load of water samples from A and C receptacles. It also, showed that there was no significant difference (p>0.05) between bacteria load of water samples from A and B receptacles. Water sample from A, had the highest CFU count of Escherichia coli, Staphylococcus sp., Streptococcus faecalis, Proteus sp, Clostridium perfringens and Pseudomonas aeruginosa of 0.62×107, followed by B water samples with Streptococcus faecalis, Staphylococcus sp. and Escherichia coli of 1.16 × 107 and C water samples E. coli and Staphylococcus sp. with count of 1.78 × 107. Proper management of culturing media in different receptacles should be monitored to reduce microbial load in Clarias gariepinus, to avoid fish mortality and ill-health to human being when consumed.