A normal fertile bull is expected to get 90% of 50 normally cycling cows pregnant within a nine week period. One in four bulls in the UK has sub-normal fertility. Reasons for this include small scrotal circumference, poor semen quality (motility or morphology) and poor serving ability.
The Bull Breeding Soundness Evaluation (BBSE) performed 4-6 weeks prior to the service period allows a proactive approach to screening out sub-fertile bulls. Furthermore, a judgement as to how many cows may be served by a bull can be attempted, rather than proceeding with no assessment of likely performance. This encourages a calculation of ‘bull power’ required prior to the service period. On average only two-thirds of sub-fertile bulls may be detected by physical examination alone.
Electro-ejaculation (EEJ) is now the standard method of semen collection used by specially trained veterinary surgeons in the UK including Rose Jackson, John Remnant and Oli Maxwell. The procedure is relatively quick (about 60 minutes) and safe providing an appropriate crush is available. The majority of the semen evaluation is carried out on farm giving you a quick idea as to the ability of your bull. The remainder is done in our own lab giving you a quick turn-around of results.