Trypanosomiasis poses a considerable constraint on livestock agricultural development in Tsetse fly infested areas of sub Saharan Africa, especially in west and central Africa. International research conducted by ILRI in Nigeria, the Democratic Republic of the Congo and Kenya has shown that the N'Dama is the most resistant breed.[5][6] In Nigeria, research has shown that N'Dama is up to 2-3x (or 25%) more resistant than Nguni cattle.