Competition for sucrose pellets in tetrads of male Wistar, Fischer or Sprague-Dawley rats: is intra-group ranking reflected in the level of anxiety?

Competition for palatable food or fluids within groups of rats has been previously used to mirror intra-group ranking. The paradigm of competition for sucrose pellets in non-food-deprived male Wistar rats was here extended from triads to tetrads aiming at evaluating whether the number of poor-performing rats, those animals being likely to model aspects of human psychopathologies (anxiety/depression/social withdrawal), could be increased. To evaluate potential superiority over the previously used Wistar strain, establishment and stability of the ranking was also assessed in tetrads of male Fischer and Sprague–Dawley rats.