Isoenzymatic changes in grass carp, Ctenopharyngodon idellus Cuvier & Valenciennes, affected with haemorrhagic disease

Abstract

Abstract. Electrophoretic analysis of six types of tissue (serum, erythrocyte, liver, kidney, muscle and eye) and seven different isoenzymes (LDH, MDH, Est, ADH, IDH, α‐GPDH and SOD) from both healthy grass carp, Ctenopharyngodon idellus Cuvier & Valenciennes, and carp affected by haemorrhagic disease was performed. It was found that: (1) Enzymes from diseased grass carp showed the most drastic changes within each tissue. The absolute activity of LDH in serum from the diseased fish increased to approximately twice that of the healthy fish; whereas the relative activity of A4 and A3B1, the main components of A sub‐base in both serum and erythrocytes, was accelerated. (2) The isoenzymic changes in the control groups, diseased fish, artificially infected fish and healthy fish from diseased ponds indicated that biochemical changes occurred in the tissues before pathological change.