Relationship between water physico-chemical parameters and growth of Brycinus macrolepidotus (Valenciennes, 1850) in Akomoje water reservoir, Ogun State, Nigeria
Water pollution is a major topic in many fisheries and aquaculture conferences, seminars and workshops as the performance and survival of any fish species depends on its environment. This study was designed to investigate the relationship between physico-chemical parameters of water and growth of Brycinus macrolepidotus in Akomoje water reservoir, South-West, Nigeria. Water parameters were measured using standard methods. Length and weight of sampled fish were also determined to the nearest 0.1 cm/g using standard equipment. Relationship between water features and length, weight was determined by correlation. All data were analyzed using Statistical Package for Social Sciences software. No significant difference (p>0.05) was observed in temperature and dissolved oxygen (28.3 - 28.5 oC and 7.6–8.2 mg/l) during the study while pH, transparency, nitrate and phosphate varied significantly. Levels of pH dropped at the peak of the dry months (January) to the onset of the rains (April). Spatial variation in all parameters was not significant (p>0.05). Length and weight were higher during the wet months (29.24–31.16 cm and 625.22-756.18 g) than in the dry months (24.45–28.81 cm and 385.71-639.20 g) with maximum recorded in June. Positive relationship was observed between length, weight and temperature. Conclusively, dissolved oxygen and temperature were within optimum range for fish growth during the study. Transparency, pH, nitrate, and phosphate were influenced by the seasons. Correlation was established between growth and water parameters.
Keywords: Dissolved oxygen, physico-chemical parameters, temperature, spatial variation, fish growth