The influences of haematozoans on different haematological and morphological parameters in a freshwater catfish Heteropneustes fossilis (Bloch.)

Heteropneustes fossilis is commonly known as singhi and considered an ideal fish species for aquaculture. It is much utilized for food and is known for medicinal properties in many parts of its range. In the present study, the influences of haematozoan infection, the fish individuals were found to be infected with the number of haematozoans of the group haemoflagellates and sporozoans of different orders, in the freshwater catfish Heteropneustes fossilis during the year 2014–2017. Giemsa stained blood films were revealed myriad stages of blood parasites and some specimens were having multiple infestations of flagellates, haemogregarine, viral erythrocytic necrosis (VEN), pycnotic erythrocytic necrosis (PEN) and haemohormadian. The haematological changes were found significant (p 0.05) for mean cell volume (MCV), erythrocyte sedimentation rate (ESR), small lymphocytes (SL) and haemoblast (H). The infected fishes were found negatively correlated with most of the parameters viz. body weight, TEC, TLC, Hb, PCV and glucose excluding MCH and MCHC. This study describes influences of haematozoans in the haematological parameters of freshwater fishes Heteropneustes fossilis.