Accumulation and response to stress in climbing perch (Anabas testudineus) on exposure to high concentrations of lead and cadmium in water

Abstract

In this study, lead (Pb) and cadmium (Cd) were used as chemical stressors. Healthy A. testudineus were exposed to Pb (20, 30, and 40 mg/L) and Cd (3, 5, and 10 mg/L) for 7, 14, 21, and 28 days to assess the response of A. testudineus elicited by these metals. The tendency of Pb and Cd accumulation in the tissues of A. testudineus was as follows: gill >> liver > muscle for Pb and liver >> gill > muscle for Cd. Endocrine stress response was characterized by varying the levels of cortisol and glucose plasma. Exposure to both Pb and Cd caused significantly increase levels of plasma cortisol (p < 0.05), while blood glucose levels slightly increased at the beginning and then decreased sharply. Based on the erratic changes in levels of plasma cortisol and blood glucose, it can be concluded that exposure to high concentrations of Pb and Cd does not cause death; however, it adversely affects the interrenal and pancreatic activities of A. testudineus. Biochemical changes can be used as biomarkers for stress assessment and management in fish.