Farmers urged to vaccinate against enzootic abortions in ewes

The National Sheep Association (NSA) is urging farmers to be wary of enzootic abortions of ewes (EAE) highlighting that over a third of sheep abortions are caused by this phenomenon.

The NSA argues that vaccinating against EAE would save money for farmers, and make “inappropriate use of antibiotics” unnecessary.

Dr. Fiona Lovatt, an independent sheep veterinary consultant, who leads the cross-industry Sheep Antibiotic Guardian Group, highlighted that farmers aren’t aware of the scale to which EAE causes abortions – it accounts for around 35% of all abortion diagnoses.

Any sheep farmer that either buys in ewes for replacements or has close neighbours that also lamb sheep, risks bringing enzootic abortion into their flock.

However, only around one million of the 3.5 million replacement ewes in the national flock each year are vaccinated against EAE, Dr. Lovatt pointed out.

“Once the disease infects an unvaccinated flock, some ewes are ‘programmed’ to abort at their next lambing, leaving no choice but to put remedial measures in place – usually including both vaccination and antibiotic treatment,” she stressed.

Once EAE is in a flock, Dr. Lovatt said, it carries “high cost” financially as well as emotionally, in terms of farmer stress.

Hence it is important that flocks receive appropriate vaccination at least four weeks before ewes go to the ram, and avoid the inappropriate use of antibiotics closer to lambing.

“There are areas of the country where sheep farmers have routinely used whole-flock blanket antibiotic treatment close to lambing to prevent abortion. There is absolutely no need for this; it is neither appropriate for disease control, nor cost effective,” she argued.

Dr. Lovatt stressed that the misuse of antibiotics can contribute to the development of antimicrobial resistance.


According to Dr. Lovatt, abortions or stillbirths cost over £25 for each lamb. By contrast, a single dose of EAE vaccine costs around £2.40, and “effectively lasts the ewe for her lifetime in the flock”.

“Every injection of antibiotics also costs an additional £1, but is just a ‘sticking plaster’ with short-lasting effectiveness in terms of disease control but long-lasting damage in terms of mounting resistance,” she added.

Dr. Lovatt has created a ‘webinar’ (online seminar) explaining enzootic abortion and the associated costs. It can be found here.