Efficacy of Aqueous and Methanolic Leaf Extract of Phyllanthus Amarus for Anti-Trypanosomal Activity in Mice Experimentally Infected with Trypanosoma Congolense

Animal African trypanosomiasis negatively affects animal health and productivity. Chemotherapy, the main means of controlling AAT is under threat due to parasite resistance and toxicity of the anti-trypanosomal drugs. The study was carried out to investigate the efficacy of P. amarus in the treatment of Animal African Trypanosomiasis with Trypanosoma congolense strain as a case study. Leaves of Phyllanthus amarus were extracted using methanol and aqueous solvents. Forty five mice weighing between 20-35g were divided into 9 groups (group 1- 9) of 5 mice each. Each mouse was infected with Trypanosoma congolense parasites intraperitoneally with 0.2 ml of blood containing a specified number (2.5 x 106 ) of trypanosomes and treated with various concentrations of 100, 250 and 500mg/bw of corresponding methanolic and aqueous leaf extract of P. amarus. Diminazine at standard concentration of 3.5mg/bw was used as control. Data collected were analyzed using analysis of variance (ANOVA) at P ≤ 0.05 level of significance. The result showed that treatment with methanolic and aqueous leaf extract of P. amarus though concentration dependent significantly resulted in marked suppressed (P < 0.05) parasitaemia and extension of survival days of the treated mice for additional 22 days against the infected untreated group. There was also a corresponding increase in the mean weight and PCV values of the Trypanosoma congolense infected but treated groups. Thus, the plants extract can be used as an alternative means in the absence of synthetic chemical drugs to sustain lives of animals infected with Trypanosoma congolense.

Keywords: Phyllanthus amarus; weight; PCV values; Trypanosoma congolense.