WESTERN Australian sheep flocks are expected to be at a higher risk of pregnancy toxaemia this year.
Department veterinary officer Anna Erickson said a range of factors including summer rains, a dry April and a higher than usual rate of twin pregnancies have increased the risk of pregnancy toxaemia in sheep this season.
The Department of Agriculture and Food is urging sheep farmers to be alert for pregnancy toxaemia in lambing ewes over the coming weeks.
Dr Erickson said pregnancy toxaemia can happen when a pregnant ewe doesn’t get enough energy intake during late pregnancy, a time when energy requirements are higher.
“Ewes with twin pregnancies are at higher risk because of the extra energy they need to grow two lambs.
“This year many ewes in Western Australia were joined on green feed and in very good condition, due to good summer rains,” Dr Erickson said.
“This has increased the number of ewes carrying twins.
“Conditions also supported a higher number of over-fat ewes, which are also at increased risk of pregnancy toxaemia.”
Hand feeding can precipitate pregnancy toxaemia
Dr Erickson said a lack of rain in April meant the early green feed had now largely disappeared, prompting many farmers to hand feed sheep.
“Hand feeding as green feed supply dries up can mean a decline in energy intake, which can precipitate pregnancy toxaemia.
“Ewes with pregnancy toxaemia are generally ‘dopey’ and not alert. Even if feed is placed in front of them they may not eat, and if lifted they seem to lack the will to walk and instead, sit down again,” she said.
Pregnancy toxaemia cases can be identified early
Dr Erickson said pregnancy toxaemia cases can be identified in the early stages.
“The ewe will separate from the rest of the mob and be slow to come up to feed.
“Ewes with pregnancy toxaemia can be treated with products containing propylene glycol given as a drench, repeated daily until a response is seen,” she said.
“Injectable 4-in- 1 calcium products contain a small amount of glucose and will produce some response, but as this is short lived, it should be combined with drenching with propylene glycol.
“Treatment is much more effective when cases are identified early, that is, before ewes go down, Dr Erickson said.
“Farmers are advised to contact a private veterinarian for information or if they see unusual signs of diseases including death or neurological signs such as lack of responsiveness affecting more than a couple of sheep.
“Australia’s access to markets for livestock and livestock products depends on evidence from disease investigations and other targeted disease testing that we are free of reportable and trade-sensitive livestock diseases. To support this testing, the department provides subsidies for private veterinarians investigating significant disease events – ask your local department vet for more information.”