Sublethal behavioral and biochemical toxicity of cypermethrin in juvenile Oreochromis niloticus in a static bioassay

  • admin admin
  • Abubakar Yaji
  • Emmanuel O. Ogueji
  • Joshua J. Ekpenyong
Keywords: behavior, biochemistry, cypermethrin, fish, freshwater, toxicity

Abstract

Sublethal behavioral and biochemical toxicity of
cypermethrin in Oreochromis niloticus (L.) juveniles was
accessed under static conditions at concentrations of 0.5, 1.1,
and 2.1 μg L-1 for up to eight weeks. The juveniles were highly
sensitive to cypermethrin, with a 96-h LC50 of 12 μg L-1.
Biphasic trends were noted for four avoidance behaviors: loss
of equilibrium; erratic swimming; air gulping; opercular
ventilation. Dose- and duration-dependent increases
occurred in mucus secretion and color change. Mixed trends
were noted for mean glutamate pyruvate transaminase,
triglycerides, proteins, and cholesterol. These parameters
decreased significantly depending on dose and duration in
weeks two and six, but they increased in week eight. Mean
glucose and glutamic oxaloacetic transaminase increased
significantly depending on dose and duration up to week
eight. No differences in glucose were noted in the control in
week two. The findings of the present study confirmed that
cypermethin adversely affected the health of fish even at
a sublethal level.

Published
2021-09-30
Section
Articles