Haematological Modulatory Effects of Combined Ethanolic Leaf Extracts of Azadirachta indica and Carica papaya in Trypanosoma brucei brucei-Infected Rats

Background and Objective: African trypanosomiasis remains a major constraint to livestock productivity in sub-Saharan Africa. Although several medicinal plants have been investigated for antiparasitic activity, limited studies have examined the potential supportive effects of plant extracts on infection-associated haematological disturbances. This study evaluated the haematological responses and safety of combined ethanolic leaf extracts of Azadirachta indica and Carica papaya in Trypanosoma brucei brucei-infected rats. Materials and Methods: Fresh leaves of A. indica and C. papaya were air-dried, pulverized, and extracted with ethanol using cold maceration. Phytochemical screening was performed using standard procedures. Acute toxicity was evaluated in Rats following OECD guidelines. Twenty-five rats were randomly assigned to five groups (n = 5): Normal control, infected untreated control, diminazene aceturate-treated group (50 mg/kg), and two treatment groups receiving combined plant extracts (400 and 800 mg/kg body weight). Parasitaemia was monitored every four days using the rapid matching method. Haematological parameters were measured after treatment. Data were analysed using one-way ANOVA followed by Tukey’s post-hoc test. Results: Phytochemical analysis revealed the presence of alkaloids, flavonoids, saponins, steroids, and phenolic compounds in the extracts. Acute toxicity studies showed no mortality at doses up to 5000 mg/kg body weight. The combined extracts did not significantly reduce parasitaemia compared with the infected untreated group (p>0.05). However, significant improvements were observed in several haematological parameters, including red blood cell count (F = 6.42, p = 0.003), packed cell volume (F = 5.88, p = 0.005), white blood cell count (F = 4.71, p = 0.011), and platelet count (F = 5.16, p = 0.008) relative to the infected untreated group. Extract-treated animals exhibited higher RBC, PCV, WBC, and platelet values relative to infected untreated controls, suggesting partial mitigation of infection-associated haematological disturbances. Conclusion: Combined ethanolic extracts of Azadirachta indica and Carica papaya did not significantly suppress parasitaemia but improved several haematological indices associated with trypanosome infection. These findings suggest that the extracts may provide supportive benefits in mitigating infection-induced haematological disturbances and warrant further investigation into their therapeutic potential.