The Curative Effcet Of Various Dose Rates Of The Drug (Cymelarsan) On A Trypanosoma Evansi Isolate

Abstract

This study was conducted for evaluating the efficiency of Cymelarsan drug on a Trypanosoma evansi isolate in experimentally infected rabbits which had a chronic infection for both treatment and protective activity.The experiment was carried out in 30 rabbits which weredivided into four groups: A group of 12 rabbits were infected with T.evansiisolate and treated with Cymelarsan. They were then grouped in pairs and each treated with a different dose of Cymelarsan drug. These doses were 5 mg/kg, 2.5 mg/kg, 1.25 mg/kg, 0.625 mg/kg, 0.312 mg/kg and 0.156 mg/kg respectively. Control groups included: 6 rabbits were infected with the parasite and left untreated. An uninfected control group of6 rabbits was treated with Cymelarsan . An uninfected and untreated group of 6 rabbits was kept as a negative control. All the groups were daily examinated for a period of 60 days post treatment. All treated groups remained alife while the infected died within 30 days post infection. VII 60 days post treatment rabbits were challenged with T.evansi. Blood from the reinfected rabbits was inoculated in mice .This revealed that all animals wereprotected except at a dose of 0.156mg/kg. This indicates that at the dose of 0,156mg/kg; Cymelarsan showed no protection and therefore it was not prophylactic after 60 days of reinfection as indicated by positive parasitaemia in sub inoculated mice.