A FOCUS on growth in maternal genetics is about to swing towards muscle and optimum fat depth.
Meat and Livestock Australia's sheep and lamb research and development leader, Alex Ball, said mature ewe size needed to be capped.
Dr Ball said 60-70 per cent of feed costs in crossbred sheep production systems were being drained by ewe maintenance.
"Maternal and Merino breeders are under the pump to select for early growth, and make sure mature ewe size is capping out at 75-80kg," he said.
"This year I've seen one flock with a mature ewe size of 120kg."
Dr Ball said terminal breeders had focused on growth rate in the past but this would change to muscle and fat depth.
"The single most important thing to put in maternal sheep is muscle," Dr Ball said.
"If there is no muscle in young maternal or Merino ewes, you are driving yourself out of business."
Speaking at MLA's Making More from Sheep forum, Dr Ball said gone were the days of buying rams without objective measurements.
"We simply cannot afford to have lambs that don't meet consumer appeal," he said.
"There will be an increased marketing focus on leaness and health aspects."
Dr Ball said competition for ewes and lambs would be at a level never seen before in the Australian sheep industry.
Merino ewe saleyard prices have jumped 88 per cent in the past five years, and 57 per cent in the past year.
"Most people would have $600-$1500/ha capital value sitting out in the paddock with their mature ewes," Dr Ball said.
There was a 40 per cent range in reproductive rate between the best and worst Merino and maternal genetics across Australia.
