ORIGINAL ARTICLE Efficacy of Kelamidium ® in the prevention and treatment of Trypanosoma brucei brucei infection in albino rats Romanus Chuks Ezeokonkwo & Ikenna O. Ezeh & Chijioke N. Iheagwam & Wilfred E. Agu & Rowland I. S. Agbede Received: 15 April 2011 /Accepted: 9 December 2011 /Published online: 24 December 2011 # Springer-Verlag London Limited 2011 Abstract The efficacy of Kelamidium® in the prevention and treatment of experimental Trypanosoma brucei brucei infection of albino rats was studied. Adult albino rats (55) weighing between 147 and 240 g were used for the study. The rats were kept in metal cages in a fly-proof house and were adequately fed and given water ad libitum. Two experiments were carried out. In experiment I (chemotherapy), 30 adult albino rats were divided into six groups of five rats each, whereas in experiment II (chemoprophylaxis), 25 adult albino rats were divided into five groups of five rats each. In both experiments, groups I and II were uninfected control and infected untreated control, respectively. In experiment I, rats in groups III and V were each infected with 5.0×10 5 trypano- somes and were later treated with 0.5 mg/kg of Kelamidium® (low-dose treatment), and rats in groups IV and VI were infected with 5.0×10 5 trypanosomes and treated with 1.0 mg/kg of Kelamidium® (high-dose treatment). Treatment was given to rats in groups III and IV at day 7 postinfection (PI; early treatment), whereas groups V and VI were treated at day 10 PI (late treatment). In experiment II, rats in groups III, IV, and V were each treated with 2.0 mg/kg of Kelamidium® at day 0 and were later infected at days 14, 28, and 42 PI, respectively, with 5.0×10 5 trypanosomes. Parasites were de- tectable in the blood of the infected rats in all the infected groups in experiment I and in group II in experiment II, 4– 7 days PI. Parasitemia, however, was not recorded in the remaining groups in experiment II. The drug cleared the para- sites from the blood of the infected rats in experiment I, 2– 7 days posttreatment (PT). Relapse of infection, however, occurred in all the infected treated groups. It was thus conclud- ed that Kelamidium® may be more useful as a prophylactic agent than as a chemotherapeutic agent in the management of animal trypanosomosis. Keywords Efficacy . Kelamidium® . T. brucei brucei . Albino rats Introduction Trypanosomes are hemoprotozoan parasites which are cy- clically transmitted by tsetse flies and affect man and eco- nomically important animals throughout 10 million km 2 of the African Continent (Barrett et al. 2003). The area affected includes large expanse of sub-Saharan Africa between lat- itudes 14°N and 29°S covering about 37 African countries (Hursey and Slingenberg 1995). The economic importance of African trypanosomosis is enormous resulting in an estimated 3 million cattle deaths annually translating into about US$6 billion to US$12 billion yearly in monetary terms (Hursey and Slingenberg 1995). It is estimated that over 1 million tonnes of meat equivalent per year and 1.26 million tonnes of milk per year valued at US$ 5 billion are being lost (Jahnke et al. 1988). FAO/WHO/OIE (1982) reported that approximately 30% of 147 million cattle in countries affected by tsetse flies are exposed to the risk of infection. FAO report (1987) also stated that over US$ 20 million are spent per year on trypanocides accounting for over 44% of the total expenditure on veterinary drugs. R. C. Ezeokonkwo (*) : I. O. Ezeh : C. N. Iheagwam : W. E. Agu Department of Veterinary Parasitology and Entomology, University of Nigeria, Nsukka, Nigeria e-mail: romanusezeokonkwo2002@yahoo.com R. I. S. Agbede Department of Veterinary Parasitology and Entomology, Ahmadu Bello University, Zaria, Nigeria Comp Clin Pathol (2013) 22:219–226 DOI 10.1007/s00580-011-1389-y