Ovine brucellosis (OB) is a bacterial disease affecting rams. It is still a common occurrence among Australian sheep flocks - a recent survey of OB in the Riverina by Senior District Veterinarian Dan Salmon found 31% of flocks tested positive for the disease. Infected rams are either subfertile or infertile, which causes moderate to severe reductions in the pregnancy rates of ewes.

A recently infected mob will usually experience a 30% reduction in pregnancy/lambing rate. This alone is an enormous cost to the business, before even considering the loss of infected rams needing replacement. On the other hand, once OB is eradicated from a flock, ram percentages can drop by up to 30%, joining periods decrease by up to 50% and lamb marking percentages increase by 30%. Clearly this is a disease worth managing out of your sheep flock.

There is no treatment or vaccination for rams already infected with OB, therefore it is prudent to:

• Have sound farm biosecurity – good fencing, ram paddocks etc.
• Get a Sheep Health Statement from the vendor, check that consigned sheep are from a flock in an OB scheme and check their flock accreditation number
• Communicate with neighbours regarding stray rams
• Don’t buy rams from saleyards or dispersal sales unless you have checked the relevant status and done your own risk assessment
• Know your own flock – learn to palpate your own rams or get a qualified vet to help
• Eradicate the disease if you are one of the 31% of flocks with it present

For help managing OB out of your flock, please give us a call.