The stock bull is a fixture in many Irish suckler farms. However, while they are the primary method of getting cows and heifers in calf in most of these operations, 3-4% of bulls are infertile.
As well as that, a further 15-20% are partially or periodically infertile according to Teagasc.
While some of the latter figure is inevitable, some of it can be prevented with early intervention. And if you identify your infertile bull early, you can minimise your losses.
Winter Management - just because they’re not working doesn’t mean they’re not there
If you don’t care for your bull appropriately over the winter period, they are more likely to become infertile.
Poor nutrition or poor management practices can have a negative effect on the bulls functionality.
When you’re housing your stock bull, give them access to a clean concrete floor. Bulls feet can become tender, overgrown and sore when they’re around straw bedding for too long.
Pens where bulls are housed should be cleaned and should provide the bull with clean water at all times.
Poor quality silage won’t cut it with your bull - as the saying goes, he is half your herd. He should get good quality silage with at least 75% dry matter digestibility.
If you can’t get your hands on good quality silage, stock bulls should be fed 3.5-4kg of meal in conjunction with ad-lib silage according to Teagasc.
However while nutrition is very important for stock bulls, be careful not to overdo it. An overweight bull will bring negative implications.
Have him in fit - not fat - condition before turning him out with the cows.
Bulls can be fertility tested during the housing period by most vets. The bull needs to have a strong libido, firm testicles with a high, fertile sperm count.
The test for sperm motility is relatively simple and only takes about 10 minutes.
Legs and hooves (especially hind legs) must be firm and sturdy. The scrotum area should free of sores, cuts and bruises.
The Moocall HEAT sensor can detect infertility in bulls when they’re out in the field. While they may be anatomically fertile, it can be hard to fully know if they are sub-fertile until they’re out there doing their job (or not).
Additionally, weather conditions, diseases or injuries picked up after housing could affect their fertility.
Have you ever been caught out by an infertile or sub-fertile bull? What did you do? Tell us in the comments.