Did you know that vaccinating for Enzootic Abortion of Ewes (EAE) can be done when it is most convenient for you?
· EWE LAMBS – vaccination can be done from 5 months of age
· SHEARLINGS (1 YR OLD +) & OLDER within 4 months of tupping/ram goes in
· ALL EWES TO BE VACCINATED NO LATER THAN 4 WEEKS before the rams go in
· DO NOT use in pregnant sheep
· Enzootic abortion of ewes remains one of the most common causes of abortion diagnosed in sheep, despite the availability of cost-effective vaccines.
· The bacterium (Chlamydophila abortus) is spread from sheep to sheep, predominantly at lambing, when affected ewes will shed large numbers of bacteria in their foetal fluids and placenta.
· Infection in a flock can result in the birth of dead and/or weak lambs from about 3 weeks before lambing is due to start.
· If sheep are infected after about 100 days of pregnancy they will not abort at this lambing, the bacteria become latent but then reactivate causing abortion at the subsequent lambing.
· The highly infectious nature of Chlamydia, as well as this latent infection means that levels of abortion can be relatively low one year, before resulting in a storm and significant losses in the next year.
· Some ewes may not abort but can still shed the bacteria, meaning neonatal ewe lambs could be infected.
· In a previously uninfected flock the infection is generally bought in.
· If you see an abortion rate in over 2% of your ewes then an infectious cause is likely.
· Don’t leave it until after lambing – the best diagnostic results are with fresh samples. Fresh samples should include the placenta where possible for EAE diagnosis.
· Blood samples can be taken from aborted ewes too but take advice from your vet about the best sampling method.
· Biosecurity and hygiene are important. Ensure ewes that abort are isolated and the placenta and bedding is disposed of, so as to minimise transmission to other sheep.
· Consider the history of where you are buying sheep from and ideally, keep bought-in separate from home-bred replacements until they have lambed for the first time.
· The best way to prevent disease is through comprehensive biosecurity and a robust vaccination policy.
· There are 2 types of vaccine available on the market, live or dead. Dead vaccines need a primary course of 2 injections and then a booster. Live vaccines require just a single injection that provides long-lasting protection (3-4 lambings, depending on the disease risk).
