Candido Rodriguez BVet Med (Mad) MRCVS CertAVP (CHP), Molecare Veterinary Services
The bull is the half of your herd. Yet in practice, he is often a neglected area in herd fertility management in both dairy and beef herds. No other individual animal makes as much contribution to the herd in terms of genetics, calves born, milk on the tank and disease status.
The routine examination of bulls, prior to breeding, to maximise bull potential and minimise poor fertility, should be a fundamental part of herd fertility management and can help avoid significant economic losses due to the use of sub fertile or infertile bulls.
The main objective of a Pre-Breeding Examination (PBE) is to identify bulls that are potentially unfit for use as breeding bulls to avoid herd fertility losses. Very few bulls are infertile, yet during a research study 20-30% of the bulls examined were subfertile and failed PBE during routine screening. A recent EBLEX bull buyers’ survey found that PBE is an underused fertility management tool.Over 65% of pedigree bull buyers would pay more for a bull which has passed a bull breeding soundness examination.
More than 40% of breeders have never had a pre-sale bull breeding soundness examination performed.
Having bulls examined prior to sale not only provides a useful marketing tool, it can also act as supporting proof that a bull is fertile if buyers later question a bull’s fertility.
Pre-Breeding Examination is all about risk management and whilst a “suitable for breeding” bull is not guaranteed to be of normal fertility, it should be of considerably less risk than a bull that has not been examined prior to breeding. A fit for purpose bull can decrease your calving interval, reduce costs and provide greater financial returns, improving your herd fertility. It is important to ask an experienced vet to perform a Pre-Breeding Examination on breeding bulls. There is a standard BCVA (British Cattle Veterinary Association) Bull Pre-Breeding Certificate that can only be signed by a veterinarian that attended a bull breeding course. The PBE should be booked well in advance. It is advised to MOT your bull 10 weeks before the breeding season begins as semen production takes over 8 weeks, so the bull must be in good health and ready for work at least 10 weeks before the breeding season starts.
The Bull Breeding Soundness Evaluation is a three stage examination with the aim of assessing the likely fertility of the bull. The three stages are:
- General Physical examination
- Genital Examination including accessory glands
- Electro Ejaculation and semen evaluation
It should be kept in mind that libido and ability to serve are not directly assessed, so bulls should be observed serving cows and you should look out for problems e.g. penis deviation (corkscrew penis) or warts. As a rule of thumb, if a bull is put with a cow in heat then he should serve her within 20 minutes and ideally within 10 minutes.
Bulls can be transiently infectious (including semen) after recent exposure to a disease. It is very important to ensure that all routine vaccinations (e.g. BVD, IBR, Leptospirosis, and Johnes) and routine treatments for liver fluke, worms and external parasites (e.g. flies, lice) are up to date.
If the bull is hired or has worked in other herds ask your vet to sheath wash them, as those bulls carry an increased risk of introducing diseases including Campylobacter.
At Molecare Farm Vets, we have experienced and trained bull fertility specialist vets. They can perform a Pre- breeding Examination in young bulls for pre-sale as routine checks before breeding period or in bulls suspected to be sub/infertile in order to certify bulls as “Suitable for Breeding”.