Haematological changes in Wistar rats experimentally infected with Trypanosoma congolense and Trypanosoma brucei brucei obtained from North-west Nigeria

Abstract

This study determined haematological changes in Wistar rats experimentally infected with local strains of Trypanosoma congolense and Trypanosoma brucei brucei. Forty-five Wistar rats between 10 – 12 weeks old weighing between 210 – 240 g were used. The Wistar rats were randomly divided into four groups (A, B, C and D), with the infected groups (B, C and D) having 10 rats each, while the uninfected control group (A) had 15 rats. Group A rats were not infected and served as the control, group B were infected with Trypanosoma congolense, group C were infected with Trypanosoma brucei brucei and group D were co-infected with Trypanosoma congolense and Trypanosoma brucei brucei. Infection was achieved using 0.1mL of blood containing approximately 1 × 103 trypanosomes intraperitoneally into each Wistar rat in the infected groups. Clinical signs were observed. The changes in the blood cells were assayed in the groups post-infection. Duncan’s Least Square Deviation showed significantly (p<0.05) higher parasitaemia in infected groups. However, group D showed a higher significant (p<0.05) difference in parasitaemia when compared to groups B and C. The pattern of mean parasitaemia for the infected groups, revealed a positive correlation with days of post-infection (p<0.05) before the decline. The packed cell volume, total red blood cell count and haemoglobin concentration were significantly (p<0.05) lower in infected groups B, C and D. The total white blood cell count, platelet counts and differential leucocyte count were significantly (p<0.05) lower in infected groups when compared to the uninfected group. These findings suggest that co-infection with Trypanosoma congolense and Trypanosoma brucei brucei obtained from Wurno and Ngaski in Sokoto and Kebbi States respectively produced a more damaging effect on haematological parameters.