Abstract

The aim of this study was to unveil the effects of imidacloprid (a pesticide) on some metabolites (albumin and total protein) and electrolytes (Na⁺, K⁺, Ca²⁺) in adult Heterobranchus bidorsalis (a common Niger wetland fish). Thirtyfive adult Heterobranchus bidorsalis (mean length, 22.43±2.42cm; mean weight, 166.70±0.33g) were acclimatized to laboratory condition for seven days and then exposed to varying sublethal concentrations of the toxicant (0.28, 0.42 and 0.56mgl^-1) in a semi-static bioassay for 14 days. Albumin and total protein were determined in the liver while electrolytes were determined in the gastrointestinal tract (GIT). Results showed that total protein were 5.00μgl^-1 at 0.00mg/l and 33.50μgl^-1 at 0.56mg/l, albumin content were 4.00μgl^-1 at 0.00mg/l and 13.00μgl^-1 at 0.56mg/l, Sodium were 20.50mmoll^-1at 0.00mg/l and 18.50mmoll^-1 at 0.56mg/l , potassium 13.05 mmoll^-1 at 0.00mg/l and 8.60 mmoll^-1 at 0.56mg/l , and calcium were 0.25mmoll^-1 at 0.00mg/l and 0.30 mmoll^-1 at 0.56mg/l. There was significant variation (P< 0.05) among the various concentrations of the toxicant for each of the parameters except for calcium. Total protein and albumin values increased as the concentration of imidacloprid increased (in a dose dependent pattern). Sodium and potassium electrolytes values decreases down the experimental group, but not in dose dependent pattern. Albumin and total protein are useful biomarker of sub-lethal effects of imidacloprid than electrolytes. Additionally, the use of imidacloprid close to aquatic environment should be done with caution.

Keywords:WQI; TSI; Use and land use; Water quality; Water resources