E. M. A. M. Bruininx - Research Institute for Pig Husbandry, Rosmalen, The Netherlands
C. M. C. Van Der Peet-Schwering - Research Institute for Pig Husbandry, Rosmalen, The Netherlands
J. W. Schrama - Research Institute for Pig Husbandry, Rosmalen, The Netherlands
L. A. Den Hartog - Research Institute for Pig Husbandry, Rosmalen, The Netherlands
H. Everts - Research Institute for Pig Husbandry, Rosmalen, The Netherlands
A. C. Beynen - Research Institute for Pig Husbandry, Rosmalen, The Netherlands