Comparative efficacy of diaminazine aceturate and isomethamidium chloride in rabbits experimentally infected with Trypanosoma brucei brucei

Abstract

The comparative efficacy of diaminazine aceturate (DA) and isomethamedium chloride (IC) was investigated in Trypanosoma brucei brucei infected domestic rabbits (Oryctolagus cunisculus). A total of eighteen rabbits were used for the study. The rabbits were divided into six groups of three each. All the rabbits in groups B – F were infected with Trypanosoma brucei brucei, while those in group A served as the negative control (uninfected and untreated group). Group B contained the infected and untreated (positive control group), Group C rabbits were infected and treated with DA at 3.5 mg/kg, Group D were infected and treated with DA 7 mg/kg, Group E contained the infected and treated with 3.5 mg/kg of DA combined with 1.0 mg/kg of IC and Group F contained the infected and treated with 7 mg/kg of DA combined with 1.0 mg/kg of IC. The weekly rectal temperature, body weight gain, packed cell volume (PCV), total erythrocyte count, haemoglobin concentration (HbC), total leucocyte count (TLC), differential leucocyte count (DLC), clinical signs and survivability and rate of parasite clearance were used to assess the efficacy of the drugs and drug combinations. The parasites cleared from groups E and F 24 hours post treatment, while in group D, it was 48 hours post treatment. The rabbits in group C and group B died within 13 – 19 and 50 – 52 days post infection (PI), respectively. Relapse was recorded in all the rabbits treated only wit DA. There was significant (p<0.05) reductions in weight, PCV, erythrocyte count, HbC and TLC. The significant (p<0.05) increase in temperature following infection were reversed by the treatments, this reversal however, was faster and lasted longer in the combined treatment groups (E and especially F) than in the single treatment group. The results of this study suggest that the combined treatments of DA and IC produced better therapeutic effect than DA only.

Keywords: Parasitaemia, Trypanosomiasis, Rabbits, Diaminazine aceturate, Isomethamedium chloride