Initiation of Trypanosoma Congolense Il3000 Procyclic and Epimastigote Forms in 109-C Medium

Trypanosoma congolense IL3000 stock obtained from the International Research Center Institute (ILRI), Nairobi, Kenya and 109-c medium were used for in vitro parasite cultivation. Different parasite seeding densities incubated at 27oC were utilized for procyclic forms initiation. The 109-c medium was found to be efficient for the transformation of bloodstream forms to procyclic stages. The computed population doubling time of 14.5 hrs and 11 hrs were observed using 2 × 105 parasite/ml and 5 × 105 parasite/ml seeding densities, respectively. In addition, phase-contrast microscopy showed that the motility and shape of procyclic and epimastigote forms are better in cultures initiated in lower or 2 × 105 parasite/ml seeding density. The peak parasite concentration was also greater in lower seeding density. Moreover, the restriction phase of cultures seeded with 5 × 105 parasite/ml was reached two days earlier than cultures initiated using lower seeding density. Furthermore, the capability of 109-c medium to initiate and support epimastigote form transformation is also reported. The results strongly indicate that 109-c medium is efficient for in vitro procyclic and epimastigote forms initiation and maintenance. It also implies that lower seeding density is more economical and convenient to maintain. Keywords: epimastigote form, in vitro cultivation, procyclic form, Trypanosoma congolense