Comparative evaluation of the chemotherapeutic efficacies of two salts of diminazene aceturate in Trypanosoma brucei brucei infected dogs

Abstract

Purpose: To compare the anti-trypanosomal efficacies of 4,4-(diazoaminedibenzamidinetrihydrate) diacetate (4,4-DDBT) and 4,4-(diazoamino) benzamidine (4,4-DB) in experimental canine trypanosomosis. Methods: The efficacies of 4,4-DDBT and 4,4-DB were evaluated in 4 groups of dogs (n = 3) designated A-D. Group A was normal control without infection or drug treatment, group B did not receive any drug treatment but was infected with Trypanosoma brucei brucei, while groups C and D were infected with T. b. brucei and treated with 4,4-DDBT(3.5 mg/kg) and 4,4-DB (3.5 mg/kg), respectively. Results: The incubation period of the infection was 6 - 9 days post-infection. Treatment of the dogs with 4,4-DDBT led to zero parasitaemia 48 h post-treatment, while there was only a decrease in parasitemia to log 6 in 4,4-DB-treated dogs. Resurgence of parasite into the blood stream occurred in 4,4-DDBTtreated dogs 6 days after initial parasite clearance. Blood analyses post-treatment revealed elevated leucocytes and lymphocytes in 4,4-DB-treated dogs (p < 0.05). Packed cell volume was also observed to be higher in 4,4-DDBT-treated group when compared to 4,4-DB group (p < 0.05). Conclusion: These findings suggest that 4,4-DDBT is more efficacious in the clinical management of canine trypanosomosis caused by T. b. brucei. However, it does not prevent relapse of infection. Based on these findings, therefore, 4,4-DDBT should be the diminazene salt of choice when indicated in the clinical management of T. b. brucei infection in dogs.