Morphometric Status of the Digestive Tract of Heterobranchus bdorsalis Juveniles Exposed to Different Concentrations of Bonny-Light Crude Oil

The morphometric status of the digestive tract of Heterobranchus bidorsalis juveniles exposed to graded concentrations of Bonny-Light Crude Oil (BLCO) was studied. The exposure of the fish to 1.00, 2.00, 4.00, 8.00 m L 1 and a control for 4 days toxicity period indicated that significant decreases (p< 0.05) in the widths and lengths of the Oesophagus (OES) Stomach (ST) and Intestine (INT) of the fish were BLCO concentrations dependent. Increased OES, ST and INT values noticed within the first 14 days of the recovery period implies that the removal of the oil pollutant from the ambient water chemistry probably rescucitated the component parts of the digestive tract of the fish both in length and in width. The magnitude of rescucitation of these component parts improved between day 14 (5%) and day 42 (15%). This implies that the ability of H. bidorsalis juveniles to recover their full and inherent capacity to utilize ingested food after water pollution is time dependent.