A Hemogram of Clarias batrachus Parasitized by Two Species of Hemoflagellates (Trypanosoma batrachi Qadri, 1962 and Trypanoplasma haematalis n.sp.) as an Indicator of Infectivity

Abstract

The blood of a freshwater catfish, Clarias batrachus Linn. was scanned for hemoflagellate infectivity by examination of fresh blood (hanging drop preparations and hematocrit) and stained smears. Trypanosoma batrachi Qadri, 1962 occurring at a prevalence of 29.5% (intensity: 4 to 20 forms/20 min scan) is reported as a new locality record (Bareilly, Uttar Pradesh, India). A new species of monomorphic biflagellate was also found in 8.1% of the infected fish concurrently with Trypanosoma. Based on its morpho-cytostatistical features, flagellar length, and AF:PF ratio, the new species is named Trypanoplasma haematalis n.sp. A few selected hematological parameters (Hb%, ESR, PCV, and MCH) of infected fish were estimated to ascertain the validity as an indicator of flagellate infection under natural and experimentally-induced conditions, by inoculation of 3 ml of infected blood in laboratory-reared, healthy uninfected fish. In either case, the blood parameters recorded significant changes up to a maximum of 55.79% (Hb%, Group B3), 151.04% (ESR, Group B3), 65.45% (PCV, Group B3), and 106.26% (MCH, Group B3) suggesting that hemograms of fishes may be utilized as indicators of some infestation, which offers scope to corroborate it with flagellate infectivity.