Study of Histopathological Changes in Experimental Trypanosoma evansi Infected Rats

Abstract

Wistar albino rats (N:30) were challenged with the local strain of Trypanosoma evansi. Each animal was infected with 5 × 105 trypanosomes intraperitoneally. The animals were examined daily for the development of clinical signs and infection status by wet blood-films made from the tail veins. The infected rats were dull and depressed from 3 DPI onwards. Postmortem examination from 5 to 8 DPI (the maximum period of observation) revealed splenomegaly, hepatomegaly, marked congestion of lungs, presence of fluid in peritoneal cavity. Histopathologically, heart muscles showed hyaline degenerative changes and haemorrhages. Liver parenchyma revealed congestion of central vein and sinusoids, binucleated hepatocytes and fatty degeneration (lipid accumulation) of hepatic cells. Thickening of interstitial space with mononuclear infiltration, areas of collapse, areas of emphysema, edema and dilated and congested blood vessels were the histopathological changes noticed in the lungs of the infected rats. In spleen giant cells aggregation, hyperplasia, thickening of capsule and trabecule were the observed changes which indicate irreversible degeneration. The affected kidney showed inter tubular hemorrhages in the cortex, medullary hemorrhages, congested glomerulus, atrophied glomerulus, desquamated tubular epithelium and disruption of renal tubules at some places.