Farmers urged to test for enzootic abortion of ewes

Enzootic abortion of ewes is the most commonly diagnosed cause of abortion in UK sheep
Enzootic abortion of ewes is the most commonly diagnosed cause of abortion in UK sheep

Vets are urging farmers across the country to test for enzootic abortion of ewes (EAE) if they experience abortions in their flock.

EAE is the most commonly diagnosed cause of abortion in UK sheep, costing the industry up to £20 million annually, according to research.

Nearly half (42%) of all diagnosed abortion cases during Q1 2020 were attributed to EAE, according to the most recent disease report by APHA.

One of the issues that could contribute to these levels of disease is the ability of the bacteria to lay latent in ewes until the next pregnancy, experts at Ceva Animal Health say.

One infected sheep aborting and then shedding at lambing has the potential to infect multiple ewes that will abort at their next lambing.

Ceva Animal Health explains that ewes can be tested for Chlamydophila abortus, which causes EAE, within three months of lambing.

Ewes warrant investigation if 2% or more of a total flock have aborted, or if two or more have aborted over two to three days, irrespective of the size of the flock.

Obtaining an accurate diagnosis in cases of abortion is key to putting future preventative plans in place, the firm adds.

Katherine Timms, ruminant veterinary advisor for Ceva Animal Health, said EAE was the most common cause of abortion in sheep in the UK.

"It can be incredibly frustrating and expensive to deal with, which is amplified by the bacteria’s ability to lay latent in ewes," she added.

“It is therefore important that any abortion outbreak is identified and managed as quickly and efficiently as possible to help prevent other ewes from getting contaminated and causing an abortion storm.

"Vaccination, along with strict biosecurity, offers the best protection against the impact of EAE and can be done any time from five months of age until four weeks prior to tupping, as long as the ewe is not in lamb.”

Tips for farmers who suspect EAE

The company has produced some guidance for farmers who suspect EAE in their flock:

• Contact your vet if 2% or more of your total flock have aborted or if two or more have aborted over two to three days, irrespective of the size of the flock

• Ideally, send the whole lamb foetus and placenta for testing. If this is not possible then arrange for your vet to take samples to send to the lab

• If there are multiple lambs from the same ewe, send the freshest foetus and placenta

• Make sure the sample is as fresh as possible as this will give the best results

• When investigating an abortion outbreak, try to sample more than one ewe

• Clearly identify any ewes that have aborted if blood samples are needed and ensure that the mark will last until sampling/repeat after shearing

• Isolate ewes for three weeks after an abortion as Chlamydophila abortus can live in the environment for this period of time

• Destroy any bedding material that the ewe could have contaminated and thoroughly disinfect the area

• Follow ‘hands, face, space’ due to the zoonotic risk