Unfortunately, some bulls are just not up to scratch. Failure to weed out the duds before they cause problems can be expensive! To help avoid this scenario, the bull breeding soundness evaluation (or VBBSE) was first devised over 60 years ago. Today, with the benefit of improved knowledge and technology, the VBBSE represents the best insurance available against bull infertility.

What is a VBBSE?

The Bull Breeding Soundness Evaluation (BBSE) is a relatively quick and economic procedure for screening bulls prior to sale or use. The Australian Cattle Veterinarians (ACV) have developed world recognized procedures and standards for conducting BBSEs and for computerizing the relevant information (see publication “Veterinary Bull Breeding Soundness Evaluation”, ACV office).

What does it involve?

Usually, the following procedures are followed:
1. A general physical examination.
2. A reproductive examination (including measurement of testicle size or scrotal circumference).
3. Collection and examination of semen (particularly for sperm motility and morphology).

In addition, a libido/serving capacity test may be included, as may special tests for diseases (e.g. vibriosis or trichomonosis). Although these procedures add predictive value to the BBSE and may be indicated in some situations, they are not mandatory.

Following these tests, bulls are placed into the following categories;
Satisfactory: All factors assessed were consistent with ACV standards. No risk factors for reduced fertility were identified.
Unsatisfactory: Some factors assessed were not consistent with ACV standards.
Q Classification Deferred: Although not all factors met ACV standards, this probably would not preclude using the bull under certain conditions. Appropriate commentary to be provided.
NT Not tested: Factor(s) could not be adequately evaluated. A retest is often recommended.

A number of trials in Australia and overseas have shown that bulls generally perform according to their classification (although individual bulls may prove to be exceptions). The economic benefits of implementing VBBSEs have been well documented and will be discussed in an upcoming newsletter.

Every year Australia must provide ongoing proof of freedom from transmissible spongiform encephalopathies (otherwise known as Mad Cow and Scrapie), to ensure we keep our export markets open.

To do this, we need to submit lots of brains to the laboratories - from cattle and sheep which die displaying clinical signs consistent with Mad Cow or Scrapie.

By submitting your eligible animals through us you will receive $300 for cattle samples and $100 for sheep samples and the cost of our visit is covered by the scheme. The incentive payment is for a maximum of two animals per veterinary investigation.

So if you have animals which fit the bill please call us! You will get paid, and you will also get a useful insight into why your cow or sheep met an unfortunate end.

It is hard for a zebra to hide in the golden brown savannah with such distinctive stripes, so what evolutionary role do their stripes play if it isn't for camouflage?

New research has opened up a different perspective on their markings. Tim Caro at the University of California mapped the distribution of zebras and their non-striped cousins, wild horses and donkeys, across Africa and Asia. He then overlaid this with maps of temperature, the distribution of large predators and biting flies. The only factor which strongly correlated with the distribution of zebras was that of swarms of horseflies and tsetse flies.

While correlation doesn't equal proof, Caro believes that the depredation of flies could be strong enough selection pressure to drive the evolution of stripes. Caro points out that instead of delivering the needle-like stings of mosquitos, horseflies slice through the skin leaving painful, slow-healing wounds prone to infection. Horseflies also have a ravenous appetite and can drain up to 500ml of blood per day from a single animal! On top of this, both flies carry diseases which are fatal to horses.

Interestingly, the rate of fly-borne diseases in zebras is much lower than in unstriped animals and analysis of blood meals from the stomachs of tsetse flies shows they dine less frequently on zebras. To add further to this suspicion that stripes are insect repellents, Eotvos University in Budapest showed that horseflies prefer eating off trays with solid paint colour rather than striped, and the thinner the stripes on the tray the greater the aversion to eating from it. That might be why the thinnest stripes are on the zebra’s legs and face - the areas the flies generally annoy the most.

Armed with this new knowledge about zebra stripes, you may come in handy at the next trivia night you attend!