As we move into winter we may begin to see cases of pregnancy toxaemia (‘twin lamb disease’) in ewes.
Twin lamb disease occurs because of inadequate energy intake during the last four to six weeks of pregnancy.
During this time a ewe’s energy needs increase substantially, as she must provide energy for both herself and her rapidly growing lamb.
Ewes that are carrying twins and triplets are particularly susceptible, hence the name ‘twin lamb disease’.
Agriculture Victoria South West District Veterinarian Dr Elle Moyle said scanning pregnant ewes for multiple lambs (twins/triplets) and prioritising their nutrition is the place to start. Maintaining and increasing the ewe’s energy intake through pasture prioritisation or supplementary feeding during the last eight weeks of pregnancy can prevent twin lamb disease.
“An outbreak of twin lamb disease is often triggered by stress and conditions that cause a low intake of food such as severe weather conditions, yarding or holding off feed.”
“Affected ewes usually appear dopey, blind and unresponsive. The condition may progress over several days,” Dr Moyle said.
“The presence of affected ewes is an indicator of the health and nutrition of the whole flock. A number of other ewes may also be affected and become further cases of twin lamb disease,” Dr Moyle said.
Other conditions which may lead to the disease include:
- ewes that have a previous history of pregnancy toxaemia
- extensive grazing situations, where the last third of pregnancy coincides with a late break in the season, followed by cold weather leading to little pasture growth
- stress, due to climatic conditions, handling, being mustered, or management procedures
- heavy worm infestation.
“Affected ewes can occasionally be successfully treated by an energy-rich drench such as glycerine, provided that the drench is given during the early stages of the disease.
“More importantly, good quality supplementary feeding should be given to those ewes most at risk,” Dr Moyle said.
For further advice please contact your private veterinarian or local Agriculture Victoria Veterinary Officer by calling the Customer Service Centre on 136 186.