SHEEP producers in NSW are being advised to put pregnant ewes on diets ahead of the lambing season in a bid to prevent risky births.
The NSW government's Industry and Investment department said an unexpected abundance of good-quality feed this year could lead to ewes over-nourishing their lamb in-utero.
"This will lead to a single lamb growing too quickly in the last two to three weeks before lambing and there is potential for this fatter-than-normal ewe having difficulty lambing," department livestock officer Chris Shands said today.
"Lambs with birth weights at 6kg or heavier have a greater chance of getting stuck during the lambing process."
Mr Shands said producers should restrict the intake of ewes grazing on high quality pastures in the last month of their pregnancies.
This can be achieved by significantly increasing flock numbers or limiting the amount of feed available.
"Under current pasture conditions this grazing management regime will be difficult to achieve, but it's a better option than losing both the ewe and the lamb through dystocia," Mr Shands said.
He also warned pregnancy-scanning contractors had this year reported that in some flocks more than half the ewes were carrying twins.
The buoyant feed conditions this season compare with previous years in which lamb survival was lower due to the risk of starvation and poor nutrition.
