Extensive swine production systems, traditional in Mediterranean Europe, pose some difficulties to the application of reproduction auxiliary techniques, as a result of inadequacies of population size and management practices. Artificial insemination (AI) is seldom used. Several authors point out the lack of AI extend as an obstacle to both genetic improvement in general and reproduction parameters in particular. Alentejano swine semen characteristics are not known and artificial insemination has not been used in Alentejano breed. This trial aimed at studying Alentejano boar semen characteristics and its inherent capability of being stored by using standard extenders (BTS, MR-A and ACROMAX) in order to allow for artificial insemination usage under Alentejo field conditions. 8 Alentejano (AL) boars and 2 contrast boars [1 Duroc x Large White (DL) and 1 Large White (LW)] were used.