Starting between Days 3 and 16 of their second or
third estrous cycle, 15 sets of three littermate gilts were
given oral altrenogest treatment (Regu-mateTM, 15 mg/
d) for 14–18 d to synchronize their subsequent estrus.
Littermates completed altrenogest treatment at the same
time, were treated with 600 IU eCG im (Folligon) on the
following day, and then randomly assigned to receive
either 5 mg pLH im (Lutropin-V), 750 IU hCG im
(Chorulon, Intervet Canada Inc., Whitby, ON, Canada),
or saline im, 80 h after eCG treatment.