EWES that were scanned in lamb and didn’t deliver a live one could have the campylobacter bacteria.
Coopers Animal Health’s Jane Morrison says it is one of the three big causes of sheep abortion in Australia.
It is hard to diagnose in your flock as most aborted fetuses are not found and therefore can’t be subject to a post-mortem.
However the strain of the bacteria that causes reproductive losses, if exposed to ewes while they are not pregnant, does nothing but build up their immunity and protect them for life.
“The risk factor is if they get infected when pregnant...if first infection is when pregnant they (the ewe) will either abort or they will have a weak non viable lamb or stillbirth,” Jane said.
“It doesn’t cause losses between conception and scanning, it is losses between scanning and marking that are the result of it.
“So we usually see it more prominently in maidens or second lambers, because if you have it on your property by the time they are on their third or fourth lamb they have probably got immunity.”
Jane said any gap between the number of lambs being marked out of your maiden or second lambing flock, and your adult ewe flock, could be an indicator of campylobacter.
“The gap should be about 10 per cent. If it is about 15 there could be a problem - they should be closer.
“I know producers in WA who were diagnosed with Campy, they started vaccinating and their maidens are now doing exactly what their adults are, so it really does have an impact on those maidens.”
It continues to impact at lambing time, resulting in weak non-viable lambe that don’t get up and going.
Ewes can get secondary uterine infections that can cause them to die or if they contract it late and the lamb survives, they will have low milk production.
“The disease itself doesn’t really cause an issue in ewes, they just get over it, but if they get secondary infection that can cause an issue,” Jane said.
It is moved by carrier sheep or carrion birds, if they eat infected an infected fetus they can carry it around for several weeks, while ewes will excrete the bacteria for up to six weeks.
It can also cause abortion storms.
“We have found a lot more of them in the past year as a lot more producers are containment feeding.
“It is spread by the faeces, the carrier ewes (you can’t identify which they are), when they are stressed, which is generally late pregnancy, if they are being containment fed they will excrete it and the other ewes will then eat it or drink it out of the trough and that is how they get infected and it causes these storms.”
Jane recommended looking out for blood stained breeches.
“When you are shearing or crutching pre lambing and you get blood stained breeches that ewe has aborted,” she said.
“If you are seeing those you have abortions going on even if you haven’t found any fetuses.”
Jane described one case study in Victoria were the producer scanned 5902 foetuses, and he picked 2021 out of the paddock, as well as losing 167 ewes.
A post mortem on foetuses and blood tests determined it was campylobacter.
“That is how bad a storm can be,” Jane said.
“But that is not what most people see, what most people see is this insidious low rate in their maiden ewes.”
Vaccination should be done at joining, with Jane reporting they find flocks that vaccinate achieve 9 per cent more lambs in younger ewes.
The most obvious application of the two shots of 2mls at joining is at rams in and rams out, as long as the first dose is pre-joining and the second dose is at least three weeks later.
Seedstock producers are recommended to vaccinate annually with a booster, while commercial flocks should administer at least one booster shot after ensuring their maidens receive the first two shots.
“It only takes 2-3 per cent more lambs to cover the cost of vaccine,” Jane said.