Sheep farmers are being urged to review their flock’s abortion risk and vaccination strategy ahead of tupping after the latest FlockCheck diagnostic results revealed continued high levels of exposure to the two most significant infectious causes of sheep abortion.
The findings were shared during an MSD Animal Health-sponsored webinar on managing sheep abortion on August 25, 2026, where farmers heard the latest disease surveillance data alongside practical advice on reducing abortion losses ahead of the breeding season.
The latest 2026 FlockCheck results, based on samples from 845 animals, showed that 74% tested positive for exposure toToxoplasma gondii, while 24% tested positive for exposure to Chlamydia abortus, the bacterium responsible for enzootic abortion of ewes (EAE).
Both diseases are classified as NOAH Category 1 diseases, meaning vaccination should be considered as part of routine flock health planning.
Sara Robson-Ingham, veterinary adviser at MSD Animal Health, said the latest figures demonstrate that infectious abortion remains a significant threat to flock productivity.
“These results show that toxoplasmosis and enzootic abortion continue to circulate widely within the national flock and reinforce why farmers should not become complacent,” she said.
“Abortion diseases can have a devastating impact on flock performance, yet they are often underestimated because losses aren’t always investigated or recorded. Every abortion should be treated as a warning sign until proven otherwise.”
With many flocks now preparing for tupping, Ms Robson-Ingham said now is the time for farmers to review last season’s performance with their vet and assess their disease risk.
“Late summer provides the ideal opportunity to vaccinate non-pregnant ewes. Vaccines need to be administered at least four weeks before tupping to ensure immunity is established before mating begins, so now is the time to act.”
She recommended reviewing barren rates, scanning and lambing performance, together with any abortion incidents from the previous season, before deciding on the most appropriate flock health plan.
“If you’ve experienced abortions, higher barren rates than expected, or poorer scanning or lambing results, speak to your vet and investigate the cause. Vaccination should form part of a wider flock health plan based on your individual disease risk.”
To watch the webinar, click here.

