Blood of two siluroid fishes during different respiratory conditions

In the present study an attempt has been made to investigate the changes in different blood parameters in two siluroid fishes, Heteropneustes (H.) fossilis. Bloch and Clarias (C.) batrachus. Linn, both air breathing fishes, during different respiratory conditions, Viz, 1. normal, 2. submerged water condition and 3. exclusive air breathing condition. An increase in different blood parameters [Viz, red blood corpuscles (RBC) counts, haemoglobin (Hb) content and packed cell volume (PCV) etc.] was observed under submerged water and exclusive air breathing conditions. Possible reasons and the mechanism of such changes in different blood parameters have been discussed.