BIOCHEMICAL CUES FOR SURVIVAL IN ACUTELY TOXIC CONDITIONS

Abstract

The relative susceptibility to toxicants is dependent on an organism’s survival strategy either innate or acquired. An assessment of the biochemical responses induced in three aquatic animals; Poecilia reticulate, Paleamonetes africanus and Clarias gariepinus exposed to acute concentrations of a petrol additive was conducted using in a 96hrs bioassay. C. gariepinus was found to be the most susceptible to the additive; having the lowest 96 hrs LC50 value (101.9mg/L) and surviving individuals of this species equally had the highest levels of lipid peroxidation damage. Although no definite interspecies trend could be inferred from the activities of the anti-oxidative stress enzymes, there was evidence of inhibition catalase, superoxide dismutase and glutathione-s-transferase relative to the control individuals in all three species. The levels of the lipid peroxidation product, malondaildehyde, showed significant (P<0.05) dose dependent relationships. Overall, the biochemical responses observed in surviving animals showed evidence of relationships with concentrations of exposure. Their use in comparing interspecies responses however, must be with caution