For Peter Whittaker, body weight is a crucial factor in breeding sheep.
And the Merino breeder has found increasing body weight in his flock is paying all sorts of dividends.
Mr Whittaker and his wife Lianne, Oaklands, Gunning, are currently running 1200 joined Merino ewes and 600 ewe lambs on their 640-hectare property.
Their stock numbers are down at the moment, due to the drought.
For the first time in Mr Whittaker's life, they aren't running any cattle, because they had to sell them to survive the dry.
Usually they would also be running around 80 Angus cows and their progeny.
But even during the drought, the fifth generation farmer was very focused on the fact that body weight in his stock could make all the difference.
The Whittaker family's focus is on breeding plain-bodied, heavier Merinos.
Ewes are joined mid-March, with maidens joined at 18 months old.
Mr Whittaker has found the ewes lamb well, and he makes sure he keeps magnesium up to the ewes.
"They are generally quite easy to lamb, and are good mothers," he said.
Lambs are weaned at around 13 weeks, and Mr Whittaker prefers to paddock wean.
Lambs are started on feeders while they are still with their mothers, and then weaned into paddocks with the feeders.
Wethers are usually shorn at 10 months old, and then sold around six weeks later through AuctionsPlus. Cull ewes are sold at the same time.
He has sown around 35ha of outback oats for his young ewes, and also about 30ha of ryecorn.
Shearing takes place once a year, with an average ewe fleece weight of 7.3 kilograms and around 16.5 micron.
Bur Mr Whittaker said a turning point for his flock was using genetics from Michael and Jane Corkhill's Grassy Creek Merino stud, Reids Flat.
"We originally started growing traditional, old school fine wool," he said.
"The sheep were small, short and tight, and cut bugger all.
"We were looking for a bigger, plainer type of sheep with better wool condition, which was more adaptable to our environment here.
"We wanted a good, big, open sheep.
"Plainer used to mean no wool, but that's all out the window now."
Mr Whittaker started using Grassy Creek, predominantly poll, rams around 12 years ago.
He said he particularly sought out rams that were twins.
He said he was seeing a massive improvement in his flock.
"Anyone who breeds livestock knows you need to not only know what you are after, but they have to click with your animals," he said.
"We have increased the fleece weight by almost double. We are now averaging at least 7.3kgs.
"The majority of our sheep are now heavy-cutting sheep."
He said drought had been a huge factor in the past 12 years, and had affected micron, but using Grassy Creek genetics had also contributed.
"Our micron has come back, our cut has gone up, and so has our body weight," he said.
"The average body weight before was 55kg, now it is 75kg."
"We are heading in the right direction.
"Our sheep are more versatile. For what we are doing, they are perfect."
He said the most recent drought had been proof of their improvement.
He was feeding ewes in a sacrifice paddock, averaging about 400g of barley a day a head.
"The condition they maintained in that really tough season was quite phenomenal," he said.
"They are tough genetics."
And it shows. After a tough season, he said they had been scanned, with approximately 75 dry, 350 carrying singles and 775 carrying twins.
He said body weight was crucial in improving a flock.
"The biggest factor in anything is body weight," he said.
"Any age sheep will join extremely badly if body weight is not optimal at joining."
Mr Whittaker said in the past three years they had begun to see the improvements they started working towards 12 years ago.
"We've really seen our hard work is paying dividends," he said.
"To get that even consistency takes time.
"We are finally seeing our hard work starting to pay off."