A new semen sexing technology in the UK could make it easier and more cost effective to select heifer and bull calves.


GB Bulls is the first UK AI company to offer Heiferplus and Bullplus which allow semen to be sexed pre-freezing or at the time of insemination, explained GB Bulls’ Bill Dennie.

Heiferplus contains an enzyme which attaches to the female sperm and stimulates its motility while slowing the motility of male sperm. When inseminated this means the female sperm swims faster and reaches the egg first resulting in more eggs fertilised by female sperm. Bullplus works by the reverse.

Trials show in the UK conception was 60% to first service and out of 290 births 221 heifers were born a 76% success rate.

Vials containing the sexing agent can be bought for £9 with one vial used for one straw meaning genetics are not limited. Alternatively straws already combined with the sexing agent can be purchased for varying cost depending on the sire.

For more information call 01782 791 441 or email bill@gbbulls.co.uk