Cyanobacteria blooms are threatening services provided by lakes, including fisheries production through exposure to cyanotoxins (e.g., microcystin, MC). Unfortunately, how MC affects fish physiology, growth, and survival remains limited for nearly all Great Lakes species. Towards this end, we conducted a laboratory experiment with juvenile yellow perch (Perca flavescens), an important species in the Great Lakes basin, exposing individuals to 1 of 3 MC concentrations (0, 10, and 20 μg/L, using cultured M. aeruginosa). We exposed fish to their treatments for 14 d (harvesting some individuals every 7 d), after which all remaining individuals were exposed to control (0 μg/L) cyanobacterial conditions in their treatment tanks (n=5 tanks/treatment). We also analyzed the effect of MC on gut microbiome of juvenile (age-0) yellow perch using the 16S sequencing approach to characterize the microbial community. In addition to this, we have applied 1 H nuclear magnetic resonance (NMR) based metabolomics analysis to study effect of MC on liver metabolism. We found a dose-dependent response to MC exposure, with MCs accumulating the liver. We also found expected dose-dependent physiological responses, including reduced glutathione peroxidase and glutathione in the livers of fish exposed to MC. In addition to reporting uptake and depuration rates, other physiological responses (e.g., liver metabolism), and performance (e.g., growth, survival) metrics, we discuss the potential implications of cyanotoxin exposure to yellow perch population dynamics.
Manjunath Manubolu will be speaking at International Congress on Biotechnology & Bioinformatics 2021 which is scheduled to happen on 13th and 14th August 2021 at Hong Kong, HKSAR.