Semen and its sperm rich fraction was collected from two Landrace and one Landrace-Large White crossbred boars (1 to 2 years old) one hour after injection of 12mg PGF2α into rump muscles. The PGF2α treatment improved libido to some extent and caused earlier erection of the penis in one boar. The duration of ejaculation, volume of semen and the total number of sperm in the sperm rich fraction increased following the injection by 32, 28 and 44%, respectively (P<0.01). The concentration and total number of sperm in the whole ejaculates increased by 23 (P<0.05) and 34% (P<0.01), respectively. No significant difference was seen in the viability of sperm in the sperm rich fraction stored at 15 C between the PGF2α injection group and the control group.
These results suggest that the main effect of PGF2α was the increase of the volume and total number of sperm in the sperm rich fraction and that those sperm rich fraction could be used for artificial insemination.
Japanese Society of Animal Reproduction