Caseous Lymphadenitis is still affecting Australian sheep. 30 years after a vaccine was introduced, this bacterial disease is continuing to influence Australian farms.
“Despite limited data on vaccine usage in Australia, it’s estimated that only two per cent of flocks nationally are fully vaccinated, despite the vaccine being 99 per cent effective,” said Dr Graham Lean, a spokesperson for the Australian Veterinary Association [AVA]. “Recent data has estimated the economic losses due to CLA to be around $30-40 million across the national flock. This includes the costs of carcass inspection, rejection of carcasses presenting with the disease and reduced wool income.”
Dr Lean is concerned that farmers are failing to see the possible value increases that vaccination could produce. “Buyers in sale yards average down the price of all sheep purchased to take into account the proportion that will have to be trimmed and rejected at slaughter,” says Lean. “However, for farmers selling directly to abattoirs they should be able to negotiate a premium price if their flock has been vaccinated against CLA.”
Lean believes an industry standard could benefit all farmers. “In theory, if the whole industry implemented an effective vaccination program, then every farm would benefit, as the benefits in processing efficiency would be reflected in a higher price for sheep meat and mutton in particular.”
Though the vaccine was created 30 years ago, more research is needed for farmers to understand the immediate benefits of an industry standard. “It also seemed likely, although not substantiated scientifically, that body weight loss from CLA-affected ewes could impact on productivity and financial returns,” says Lean.
“We need to know more to demonstrate to sheep farmers that there’s an immediate on-farm benefit from implementing a full CLA vaccination program. This includes animal welfare considerations.”