Cavan Station's genomic plan

Cavan Station's general manager, Matt Crozier, said he was trying to get the best genetics and had been doing artificial insemination programs with the herd of about 800 Angus females, based south of Yass.

Through this, he came up with the idea of breeding a few bulls.

"Out of the 200 of our own commercial heifers, we did a genomics test and ranked them, kept the top indexing 40 and AI'd them to (Millah Murrah) Paratrooper and that was our first lot of progeny to hit the ground," Mr Crozier said.

"Everything is DNA tested at birth. We are doing birthweights, 200- and 400-day weights, and obviously all the fertility information, so we are essentially generating EBVs (estimated breeding values) for the nucleus," he said.

Read also:

The operation now has 2021-drop heifers that have full pedigrees and EBVs which had been artificially inseminated to Millah Murrah Nugget.

"It (the nucleus) has grown a bit. I think with the AI and joinings we have about 75 nucleus cows now, so we are breeding about 30 bulls a year," Mr Crozier said.

"And we are culling pretty hard so we aim to finish at about 20 bulls that we can use.

"And we might not have to keep it (nucleus) at that size forever, but our cow herd will keep building. We might get back up to that 1200 cows so you're probably going to need 10 to 15 replacement bulls a year anyway with a herd that size."

By having the females genomically tested, an index value and estimated breeding values can be formed and means the culling process goes one step further.

"If you have a pretty even line of cattle that are all pretty structurally sound and they have all performed and got in calf when they needed to, if you want to be keeping the best of the best every time, you can then use that data," Mr Crozier said.

"If you have a few heifers falling outside the parameters of the breeding objective then you can let those ones go or drop them back in to the commercial herd."

With EBVs on all the females in the nucleus, Mr Crozier said it was a "gamechanger".

When it comes to calving, Mr Crozier said it was useful to have a figure on calving ease, gestation length, and days to calving rather than just relying on birth weight.

"IMF (intramuscular fat) is pretty important so we are keeping an eye on that, and growth, but not at the detriment of everything else," he said.

"We want good maturing animals that don't eat a lot of feed, so feed conversion is pretty important.

"You want an animal that is fertile, structurally sound, gets a calf on the ground, the calf grows quickly, early, and then is available to go in to a range of markets.

"Breeding is about balance, there is no point chasing one or two traits excessively at the cost of other traits."

Mr Crozier said another reason the business went into this was because he understood the science behind it after doing the same testing in its Bogo Merino stud.

"We were already doing it all with the Merino stud ... and we love genetics, we enjoy genetics, and we love breeding animals, whether it's sheep or cattle," Mr Crozier said.

"We want to breed the best possible animals we can.

"We thought we would extend it over to the cattle side of the business. We already knew the science and how to go about it so we did it."

Having bought bulls solely from Millah Murrah Angus at Bathurst, for the past 12 years, the Cavan Angus herd was comprised completely of Millah Murrah-sired females, but had not always previously been a pure Angus operation.

Pre-drought, the station had used Wagyu sires over the Angus heifers to produce first-cross progeny, but for the past three years, the focus had been on rebuilding Angus female numbers.

"We feel like we have gained a bit of critical mass again with numbers, (so) we are going to go back down the F1 (first-cross) Wagyu path," Mr Crozier said.

"We identify the Wagyu-cross as being something we can produce that suits our production system and our environment, that puts us as far up the quality production end as we can get."

Cavan Station recently purchased 140 Angus heifers that were pregnancy-tested-in-calf to Sumo Wagyu bulls, which were to "get our toe back in the water".

With these new heifers set to calve in winter, Mr Crozier said he would join some of their own Angus heifers to Wagyu bulls in spring.

In doing this, Mr Crozier said he didn't have to worry about selecting heifer bulls.

"We will analyse it as we go along, but the bought heifers, we may join them to Wagyu again because they are not our genetics," he said.