Comparative efficacy of trypanocide brands against experimental Trypanosoma brucei brucei infections in mice

African animal trypanosomosis is a major constraint to livestock production in sub-Saharan Africa. Chemotherapy remains the primary control strategy, but the efficacy of various trypanocide brands in circulation in Africa, especially in Nigeria, remains uncertain. This study aimed to evaluate and compare the efficacy of selected, commonly used commercial brands of diminazene aceturate and isometamidium chloride against experimental Trypanosoma brucei brucei infection in mice. A total of 35 adult male mice were randomly assigned to seven groups of five mice each. Group 1 served as the uninfected control, while groups 2-7 were intraperitoneally (i.p.) infected with 10⁶ trypanosomes. Group 2 was left untreated, while groups 3-5 were treated with diminazene aceturate brands (TrypanocideDA 1-3) respectively at a dose of 7.0 mg/kg on day 13 post-infection (p.i). Groups 6 and 7 received isometamidium chloride brands (TrypanocideISM 1 and 2) respectively at a dose of 0.5 mg/kg on day 13 p.i. Efficacy was assessed through clinical signs, parasitaemia, haematological parameters (PCV, Hb concentration, erythrocyte count, leucocyte counts), parasite clearance time, body weight, rectal temperature, and survival. Parasite clearance was fastest in group 3 (2.4 days post-treatment) compared to other treated groups (3 days post-treatment). Diminazene aceturate-treated groups exhibited shorter relapse times than isometamidium chloride-treated groups. Treatment reversed the reduction in haematological indices across all groups. The study concluded that isometamidium chloride brands demonstrated superior efficacy compared to diminazene aceturate brands in treating T. brucei brucei infections.