Current published text states that origins of all domesticated cattle can be traced back to two main centres, Asian (Bos indicus) and the Near East-European (Bos taurus). Due to recent improved technology in the methods of genetic identification and new archaeological findings, there is now believed to be a third origin, which was a native African taurine, centred in the Saharan Belt of Africa (Bos taurus),.
"Genetics studies at the International Livestock Research Institute (ILRI) have shown that the genetic composition of the Kenyan Boran is unique. If the genetic background of the Kenyan Boran is predominantly zebu, the breed also contains taurine background of two separate origins. A European-Near East taurine background of some antiquity and most likely also from recent crossbreeding and an African indigenous taurine background which is not found in any Asian zebu crosses such as Sahiwal or Brahman" (O.Hanotte. See also M.Okomo et al. 1998, J.E.O Rege et al. 2001).
As revealed by O.Hanotte at ILRI, they have shown that the Boran genome contains three distinct genetic influences. Other than the Zebu influence (Bos indicus), there are influences from both the Near East-European Bos Taurus as well as a distinct influence from native African Bos tarus. The predominant influence was however from the Zebu.
"The Zebus of the second wave have thoracic humps and started to come into north-east Africa in the 4th century AD, but the major importations date only from the time of the Arab invasions which started in 669 AD." "The Zebu were becoming common in Kenya in the 15th century." Ian Mason, (Factors Influencing the World Distribution of Beef Cattle. F.A.O.1974).
From this 'genetic package', came the Borana cattle in Ethiopia, which became the dominant breed type of the region known as the East African Shorthorned Zebu. They are typically the cattle kept by the Borana in Southern Ethiopia and the Somali and Orma tribes of Kenya. From these types came the Boran as adopted by commercial cattlemen in Kenya who developed the breed we see today.
The Boran now found in Zambia, Tanzania, Uganda, Australia and USA originated from genetic exports of Kenyan Boran cattle between the 1970's and 1990's. The breed in Zimbabwe and South Africa came from embryos exported from the excellent facility on Ol Pejeta Ranch at Nanyuki, Kenya, during 1994 and 2000.