CSIR 3rd Biennial Conference 2010. Science Real and Relevant. CSIR International Convention Centre, Pretoria, South Africa, 30 August – 01 September 2010 As a consequence of natural selection in stressful environmental conditions, the Nguni cattle have been reported to be metabolically superior under unfavourable conditions, thus indicating an adaptive measure to survive times of poor feed quality. Compared to European breeds such as the Hereford, this indigenous Nguni breed is less susceptible to drought, parasites, diseases and insects. It is also widely acknowledged to be the outstanding beef breed for optimal production under harsh African conditions. One of the features that enable the Nguni to survive under these adverse conditions is their nitrogen cycle pathway which is believed to result in the animals being less dependant on dietary protein than other breeds. It is speculated that this could be partly due to the maintenance of high blood urea levels when the nitrogen content of the pasture drops