Figure 4.

Three possible pyramidal selection schemes according to the magnitude of G × E interactions between thermoneutral (TN) and heat stress (HS) conditions; (a) current situation of pig breeding; (b) a pyramidal device that takes into consideration the phenotypic information obtained from multiplication farms located in different environments (case of weak to moderate G × E interactions); (c) case where the G × E interactions are strong and where it becomes essential that the environment of selection is not different from the environmental conditions of production.