Abortion survey prompts warning at lambing

Any farms with a 2% abortion rate should investigate enzootic abortion in ewes (EAE) this lambing season, say vets reacting to new industry data.

Two years of subsidised abortion testing scheme results show almost half of aborted material sent for analysis tested positive for abortion caused by chlamydia abortus.

Ceva Animal Health claims these figures from its Assure Ewe scheme demonstrate EAE remains the most common cause of abortion in sheep in the UK.

See also: Guide to preventing enzootic abortion in ewes

In 2021, 48% of submissions tested positive for EAE, mirroring findings from testing in 2020, said the veterinary health company.

Enzootic abortion in ewes: advice

  • Record instances of abortion as accurately as possible
  • Seek vet advice and test abortion materials if you have an abortion rate of 2% or more, or two ewes aborting in a two-to-three-day period, irrespective of flock size
  • Remember that Chlamydia abortus can be tested from three weeks to three months after lambing
  • Act on results quickly – once infected sheep start aborting and shed bacteria, there is potential to infect multiple ewes that will abort at the next lambing
  • Seek veterinary advice on vaccination. Along with biosecurity measures, vaccination is the best protection against EAE

Source: Ceva Animal Health

Significant problem 

Katherine Timms, ruminant adviser at Ceva Animal Health, said: “EAE is a significant problem on UK farms. It can be exceptionally expensive and frustrating to deal with, as infected sheep aborting and shedding have the potential to cause an abortion storm the following year.

“Any abortion outbreak should, therefore, be identified and managed as quickly and effectively as possible to help prevent the rest of the ewes in the flock from becoming infected.”

Vaccination offers an excellent means of control for farms buying breeding replacements from non-accredited sources, said the National Animals Disease Information Service (Nadis).

“Freedom from C abortus infection is best achieved by maintaining a closed clean flock with strict biosecurity measures, although there have been rare situations where infected material has been transmitted between neighbouring farms by birds or foxes,” said Nadis.

“Various accreditation schemes are operating which offer breeding female replacements from flocks monitored free of C abortus infection.”