Correlating metrics of fish health with cellular indicators of stress in an Arkansas Bayou

Linear regression analyses were performed relating biochemical markers of exposure in livers of feral largemouth bass to a 14 metric fish health index based on morphological and physiological observations in centrarcids. Female largemouth bass were collected at seven sites along Bayou Bartholomew in Southeastern Arkansas. Hepatic cytochrome P450 1A (CYP 1A), ethoxyresorufin- O-deethylase (EROD), heme oxygenase (HSP30) and metallothionein (MT) were measured in each animal and compared to the FHI determined for each individual. An inverse relationship was observed between CYP 1A expression and FHI, indicating that healthy fish expressed more CYP 1A than morphologically or physiologically altered individuals. In addition, a direct relationship was present with the acute stress protein, HSP30, indicating that animals with poor health may have been experiencing acute biochemical stress. These results demonstrate the usefulness of multiple biochemical indices and their relationship to whole animal responses in feral animals.