Abstract:
Afiican trypanosomosis affects health and productivity of livestock and is an important constraint in development and well-being of rural smallholder farming communities in sub- Saharan Africa countries including Kenya, Uganda and Tanzania. Difierentiai expression of the disease has been observed across savannah foci of the T rypanosoma congolense, a major causative parasite of the animal disease. The current investigations were conducted to establish if the dilferences in the disease manifestation were due to variations in strains and/or phenotypes of the parasite in the various foci. Swiss white mice were inoculated with T. congolense strains from Kiboko ranch (Kenya) KETRI 2879, Lugala (Uganda) EATRO 2267 and Robanda/Ikorna (Tanzania) EATRO 2026 foci and their pathogenicities regularly monitored by quantifying the parasiiaemia, packed cell volume and albumin levels, in addition to body weight, pre-patent period and survival parameters for a period of 60 days. Findings indicated that T. congolense savannah was the most prevalent subtype in the three oounnies with a few cases of mixed infections being observed. Following infection, parasites were observed in blood, resulting in decreasing in PCV and albumin levels. The three T. cungolense savarmah subtypes from the three foci showed differences in their pre-patent period, PCV, albumin levels and parasitaemia levels and pattern. The subtype from Tanzania was the most pathogenic although it had the longest pre-patent period. The finding also confirmed diflerences in the pathogenicity among the three T. congolense savannah strains firom the three foci which may be responsible for the differences in disease expressions observed in natural infections.
