© 2017 The Authors.
Copyright resides with the authors in terms of the Creative Commons Attribution 4.0 South African License.
Condition of use: The user may copy, distribute, transmit and adapt the work, but must recognize the authors and the South African Journal of Animal Science.
Except where otherwise noted, this item's license is described as © 2017 The Authors. Copyright resides with the authors in terms of the Creative Commons Attribution 4.0 South African License. Condition of use: The user may copy, distribute, transmit and adapt the work, but must recognize the authors and the South African Journal of Animal Science.