Petali Merinos principal Martin Oppenheimer, Walcha, had seen a growing trend towards WEC ASBVs for four to five years.

“It’s become a yes or no thing for many producers – if the ram doesn’t have good WEC figures they won’t buy it,” he said.

“There’s been quite a premium for rams with high worm resistance, at our sale this year it could have been up to $1000.”

This was also evident at the recent Cressbrook Merino ram sale at Armidale last week where the stud’s 118 rams averaged $2356.

Cressbrook principal Lach Fulloon said the majority of his clients were interested in WEC ASBVs.

“Rams with superior WEC figures are in demand from producers,” he said.

Southern Queensland grazier and top-priced ram buyer at Cressbrook, Don Thomas, “Llancaut”, Wallangarra, said he placed a “big emphasis” on buying rams with negative WEC ASBVs.

“It’s one of the main reasons we’ve started buying rams here (at Cressbrook),” he said.

Kim Barnet, Miramoona Merinos, Walcha, has also noticed an increase in demand for worm resistance.

“It’s been growing in the past few years, but this year it has been especially strong,” he said.

Mr Barnet said with so much rain in the New England during the past two summers, which had provided ideal conditions for worms to thrive, producers were looking for an alternative to drenching.

“More studs are starting to do it (display WEC ASBVs), but also people are seeing and hearing of good results from selecting for WEC figures,” he said.

“Producers are starting to understand ASBVs more and how they work and are using them more.”