Available online at www.journalzbr.com ISSN No: 2349-2856 Journal of Zoological and Bioscience Research, 2015, 2, 1:23-27 23 http://www.journalzbr.com/issues.html Possible transplacental transmission of Trypanosoma evansi in experimentally infected albino rats S.Y. Argungu 1 , A.Y. Bala 1 , Q. Majeed 1 , M. Usman 1 and A.A Umar 2 1 Department of Biological Sciences, Usmanu Danfodio University, Sokoto 2 Department of Veterinary Medicine, Usmanu Danfodio University, Sokoto Correspondence: samailayakub@yahoo.com (Received: 05/03/15 ) (Accepted:21/03/15) _____________________________________________________________________________________________ ABSTRACT This study was aimed at determining the possible transplacental transmission of Trypanosoma evansi in experimentally infected albino rats. Eight, two weeks pregnant female albino rats were used for this study. Infectivity was achieved using blood containing approx. 4.0x10 6 trypanosomes/ml of blood from donor rats. Prepatent period, clinical signs, abortion and possible transplacental transmission of the parasite were parameters monitored during the experiment. Two days Post Inoculation (P.I) confirmed the take-up of infectivity due to the presence of the parasites in the peripheral blood of the hosts using Standard Trypanosome Detection (STD) technique. The results of the study showed that five experimental rats had abortion of pregnancy giving a percentage of 62.5, while the remaining rats delivered a total of 9 offspring. All experimental animals later died with Average Survival Time (A.S.T) of 50.6 days Post Inoculation (P.I) Lassitude, lacrymation, salivation, oedema especially of lower limbs, emaciation, and corneal opacity were observed prior to the death of the rats. Findings from this study also revealed the complete absence of the parasite from the peripheral blood of the offspring for up to 10 weeks of tail blood monitoring. This led to the conclusion of the failure of the parasite to cross the placenta of the parent rats to cause infection in the offspring. Studies were underway to further explore and elucidate the possible transplacental transmission of T. evansi in different animal models. Key words: T. evansi, Abortion, Transplacental transmission, Albino rats. _____________________________________________________________________________________________ INTRODUCTION The disease trypanosomosis is caused by the pathogenic protozoa of the genus Trypanosoma. It has a wide distribution and economic importance in African countries, mainly in regions occupied by its biological vector [1]. Trypanosoma evansi is primarily transmitted mechanically by biting of blood-sucking insects like Haematobia, Tabanus, Stomoxys, Chrysops spp and Hippoboscidae [2; 3]. These insects act only as carriers because of the parasites inability to undergo any developmental activity in the vector. Trypanosomosis may still be artificially transmitted through the shared use of a needle for several animals during application of medications or vaccinations [4]. The adaptation to mechanical transmission has been responsible for the rapid spread and wide geographical distribution of the parasite [5]. The clinical signs seem to vary among hosts depending on the virulence of the isolate, the susceptibility of the hosts and the presence of concurrent infections, stress, malnutrition or adverse climatic conditions [6]. Initial multiplication of T. evansi occurs at the inoculation site, particularly in the dermal collagen, which triggers the development of a cutaneous necrotic oedematous lesion known as chancre; a cutaneous swelling in which the first trypanosomes multiply [7] accompanied by an intense local immune reaction and cellular infiltration [8]. This initial