Jennie Macky's pretty quick with the snip - she can perform up to 10 vasectomies an hour.
Jennie vasectomises young bulls that then go into dairy herds to identify cows that are ready to be mated.
The qualified vet says the teaser bulls have all the urges of a non-vasesctomised bull and will leave farmers with very little doubt when it's time to call the artificial breeding technician.
"As a vet, when I get presented with a group of non-cycling cows there is a percentage that have been on heat but have just not been seen....when teaser bulls are run with theses dairy cows they (they cows) tend to display a lot stronger."
Jennie has more than 200 teaser bulls she leases out when they're 15 months old. When their job is done they are sent straight to slaughter.