Sheep producers who have experienced more than 2% of ewes aborting this lambing season are being urged to take advantage of the new subsidised blood testing service available from vets that detects exposure to enzootic abortion (EAE) and toxoplasmosis.
FlockCheck 2012, a subsidised diagnostic service from MSD Animal Health, requires vets to take blood samples from 6-8 aborted ewes. And at a time when many farmers are asking for veterinary diagnostic support to confirm or rule out potential Schmallenberg virus infection, it makes sense to investigate whether other diseases are present in the flock at the same time.
Data collected nationally shows that the most commonly diagnosed causes of abortion in sheep continue to be EAE and toxoplasmosis, despite the availability of cost-effective vaccines.
"Based on the previous two years’ FlockCheck data (2011 and 2010), on average over 86% of submitted samples tested positive for toxoplasmosis and more than 62% were positive for enzootic abortion. Around 43% of samples showed exposure to both diseases," says MSD Animal Health ruminant veterinary adviser Drew McGurren MRCVS.
With lamb prices still remaining buoyant it has never been more important to ensure farmers minimise lamb losses. The 2012 FlockCheck service allows vets to identify whether toxoplasmosis or enzootic abortion is the cause of any aborted lamb losses and provides a basis for discussion with farmers about the potential value of vaccination programmes with Enzovax and Toxovax.
"The recent FlockCheck results are consistent with findings from previous years, in that around four out of every five tested flocks are infected with toxoplasmosis. Additionally, we also find consistently that slightly more than a third of flocks are harbouring both toxoplasmosis and EAE infections. Unfortunately, whilst EAE can cause abortion storms, many farmers may not realise they even have a problem, but there’s no doubt that these infections do erode flock profitability."
Drew McGurren explains that the costs of lowered productivity are so great that vaccination is a highly cost-effective route to disease control. "If toxoplasmosis is present in your flock, vaccination has been shown to produce a 6.4% increase in the number of lambs. The situation can be more complex with EAE if many ewes are already carriers of the disease. However, most farms will see a significant benefit from vaccination during the following season.
"Assuming ewes are vaccinated with both vaccines at the start of their productive life in the flock (which is normally five years), any 100 ewe flock only needs to produce an extra three lambs a year to pay for the investment," he says.
FlockCheck 2012 – and the abortion vaccines Enzovax and Toxovax – are available from veterinary surgeons. Farmers interested in taking up the subsidised diagnostic service offer are urged to contact their local practice.
