Haematological changes in domestic fowl experimentally infected with the cestode Raillietina tetragona (Molin, 1858)

Haematological alterations in domestic fowl following three levels of infection with 20, 50 and 100 cysticercoids of Raillietina tetragona (Eucestoda) have been studied over a period of 8 weeks. The infected birds showed significant haemoglobin depression. There was no significant change in the packed cell volume (PCV), RBC counts or mean corpuscular haemoglobin (MCH). In all three levels of infection, the calculated mean corpuscular volume (MCV) increased, while the mean corpuscular haemoglobin concentration (MCHC) decreased considerably. Macrocytic anaemia along with hypochromia could be noticed during different periods of infection. Total white cell count diminished significantly in infected birds. There was a significant lymphocytopenia concurrent with a significant increase in the percentage of heterophilic elements. Eosinophilia was not a consistent feature. Erythrocyte sedimentation rate (ESR) increased significantly in infected birds. The changes in the blood picture were more pronounced in birds infected with 50 and 100 cysticercoids.