Pre Breeding Bull Fertility Examinations

Why bother testing bulls?

When using natural service, 50% of your herd’s fertility is in the bull. If he doesn’t work there aren’t any calves. With a totally infertile bull, this is usually apparent within three to four weeks as cows return to oestrus. The more damaging case and more difficult to diagnose is the sub-fertile bull. A sub-fertile bull will give you calves but the calving pattern is stretched out. This is because he has low levels of healthy sperm and so can get cows in calf eventually. 

When to test?

The timing of a test is a bit of a balancing act. Too early and you increase the time period between testing and the bulling period and so increasing the time in which things could go wrong. Too late and you haven’t got enough time to go out and buy (and test) a new bull before the breeding season. I’d suggest a month to six weeks before the season begins.

What’s involved?

• There is no need to have a cow in season when taking a sample.

• The bull needs to be restrained; ideally in a crush with side opening doors.

• The bull is examined generally. Then his testicles and internal sex glands are examined.

• A probe is placed in his rectum which allows us to collect a sample by electro ejaculation.

• A small lab can be set up in a kitchen or in a warm workshop.

• The sample is assessed there and then.

•  A certificate is completed if required.

 What’s the outcome?

• The conclusions will be that the bull’s fertility is satisfactory or unsatisfactory.

• If the bull hasn’t been observed serving cows, his ability to do so needs to be known. This is usually the farmer’s job to see the bull work in the field.

• Remember this test will not predict future fertility. It assesses the fertility of the bull on that day. 

How to arrange a test?

• Ring one of the branches and the reception staff will be able to arrange a visit.

• Mark and Jim fertility test bulls and you may want to discuss a case with them before deciding to test.

• We are willing to travel outside our normal practice area and do this fertility work on behalf of your own practice.