Bulls need to be in top shape in order to achieve maximum success. Their body condition should be on target – BCS 5+ for dairy bulls and 6+ for beef bulls – and they should have adequate trace element levels (magnesium, copper, selenium and zinc). All bulls should meet minimum scrotal circumference targets for their age and breed prior to mating and should have sound sexual organs.  

It’s also a good idea to check they have healthy, high-quality sperm to avoid any disappointment come scanning time! We can come out to do a breeding soundness exam on your bulls, which includes a physical inspection and collection of a semen sample. This sample is then tested for density, motility and deformities, and the bull is allocated a fertility score based on his results. 

Other key points:  

• Ensure they don’t have any illnesses or injuries, or deviations in posture which affect their biomechanics and would impact their ability to breed.  

• Check they have sound eyes.  

• Make sure they have had their annual lepto vaccine and a BVD booster vaccine at least 4 weeks before mating starts. Virgin bulls should be blood tested for BVD as well as vaccinated.  

• Treat injured bulls as promptly as possible and allow them plenty of time to rest and recover. 

• Have some spare bulls on-farm to swap in if one becomes injured.  

The recommended bull:cow ratios, for both dairy and beef herds, are 1:25 for yearlings/unproven bulls and up to 1:40 for mixed-age, fertility tested bulls. However, if you are synchronising your cows, you may need to use more bulls. 

Using subfertile or unfit bulls can be very costly, so make sure you select the right boys this season. And remember, even if a bull ticks all the boxes, it pays to watch him in the herd to make sure he’s doing the job properly!