Table 1.

Features of the extenders used in this study.

Trade name	Distributor	Fraction	Duration of storage
MR-A 3	Kubus, s.a. and general farm	1	Short term
BTS	Minitub	1	Short term
Androstar-Plus	Minitub	1	Short term
Modena 1	Semenitaly	2	Short term
Mr Pig Sire	Pig service	2	Short term
ZM	Microgene	2	Short term
HP2000	Microgene	2	Long term
Sus	Medichimica	1	Long term
Tri X-Cell	Imv technologies	1	Long term