With many bulls being sub fertile, it is a good idea to check that they are still in full workiing order before being used. Our highly experienced vets will carry out a full physical exam as well as semen analysis.
Bull fertility is a largely overlooked, but very important, part of your herd's fertility.
While a truly infertile bull is very rare, we much more commonly see sub-fertile bulls, who can get cows in calf, but are not as effective as others, causing more empty cows at the end of the season and a more drawn out calving window.
It is estimated to cost between £400 and £800 to keep a cow for a year, so empty cows are bad for your business.
The cost of a bull breeding soundness exam is vastly outweighed by the cost of having a group of cows not in calf, or a drawn out calving period.
Bulls can become infertile or subfertile at any time, so a fertility test before each breeding season is recommended.
Causes of loss in fertility can range from physical trauma to the penis, infection in the testicles or epididymus, or even general infection elsewhere in the body that may cause a temporary increase in body temperature.
The sperm takes a couple of months to be produced and mature, so any issue a couple of months ago will still effect semen quality today.
To carry out a fertility test we first perform a basic physical exam of the bull, listening to the heart and lungs and assessing for lameness.
We next perform a more specific reproductive based exam, feeling and measuring the testicles, putting an arm in rectally to feel the accessory glands, and get a semen sample using an electroejaculator.
This sample is looked at with the naked eye, then under magnification on a microscope to assess how well it seems to be moving, and how concentrated the sample is. Finally a stained sample is made to look at under high magnification at a later date to look at individual sperm cells to look for defects.
This gives us a very good idea if the bull is capable of getting the required number of cows in calf, at this time.