Sub-lethal effect of glyphosate on some antioxidant response and haematological parameters on fingerlings of heteroclarias

Abstract

This study was carried out to determine the sub-lethal effect of glyphosate on some antioxidant response and haematological parameters of fingerlings of Heteroclarias. The toxicant was introduced at varying concentrations of 0.00mg/l, 0.30mg/l, 0.70mg/l and 1.40mg/l for eight (8) weeks. For sub-lethal studies, catalase activities for gill shows increase in activity from 2-4 weeks and 6-8 weeks increased from 0.30mg/L which increased again from 0.70-1.40mg/L. The catalase activities for liver decreased with increase in concentration. The peroxidase activities for gill and liver shows increase in activity as the concentration increased from 0.30-1.40mg/L for 2-8 weeks (p<0.05). The sub-lethal toxicity bioassay also showed dose dependent reduction in packed cell volume (PCV), red blood cells (RBC) and haemoglobin (Hb). The toxicant led to significant changes (p<0.05) in haematological parameters as the toxicant concentration increased. Mean Red Blood Cells (RBC), Haemoglobin content (Hb), Packed Cell Volume (PCV), reduced as the concentration of toxicant increased while other parameters increased proportional with the toxicant concentration. The number of white blood cells (WBC) increased in glyphosate treated fish. The results are statistically significant at p<0.05 level.

Keywords: glyphosate, antioxidant, haematology, Heteroclarias