Looking to have more control over the cattle they were selling, they decided to venture into breeding, having been steer buyers and fatteners all their lives.

And, because it was where the opportunity lay at the time, they bought country a long way west of their central Queensland grass properties and feedlot - into the Northern Territory.

It was low-rainfall desert country that they weren't familiar with and few people they knew were.

Today, the brothers describe it as they best move they made.

So long as you have faith in the long term beef game, and a passion for it, then taking opportunities where they present will pay off, John Speed says.

"I'm nearly 60 now and have been in beef all my life. At the moment, we're making the best money out of cattle we ever have and I can't see it going backwards," he said.

"For 30 years we sat on $1000 for bullocks. Over the past couple of years that crept to $1500 and at the end of this season, we sold $2000 bullocks.

"That's a leap I believe is permanent. The demand is just so strong for Australian beef."

John and Marg Speed, with sons Ben, Jack and John and daughter Sally, and Bill and Gretchen Speed, with sons Bob and Tommy and daughter Emily run Brigodoon Cattle Company. It's breeding properties span 1.2 million hectares across Talton Downs and Tobermorey Station on the Territory/Queensland border and Linda Downs nearby in western Queensland.

The move into breeding, John Speed explained, was borne out of the desire to influence both the genetics and the supply of the cattle available to the central Queensland fattening and lot feeding operations.

"We breed for marketability," he said.

"Growth rate is a big thing but it's the scope to have a beast saleable at any particular time in its life that is the real driver.

"Plus we've been ruthless on fertility, we've worked at that hard. That's where the profit is."

The breeding country is currently running 30,000 head, with the herd predominantly Santa Gertrudis.

Weaner steers and cull heifers are trucked east, generally at 250 to 300 kilograms, to be grass fattened or 100-day grainfed to supply Kilcoy and JBS. Most of it goes overseas, largely to Korea and Japan.

Cull-for-age cows and non productive cows are fattened in the Territory.

The Speeds also sell to the live export market, mostly for shipments to Vietnam and generally two-year-old steers or mickey bulls.

Decisions on how many go to that market are made as per what the market is paying but Mr Speed said it was growing as a percentage of the business. This year around 15 to 20pc went that way.

It's been an above-average season at the breeding properties.

In March, floods covered all the country, causing huge damage but the good outweighed the bad, Mr Speed said.

"We're still operating off that and it will get us through until February, although that won't be the ideal," he said.

"Before that, it was very ordinary. We were shifting calves under 100kg east."

Not many people realise how highly productive the Territory country can be, Mr Speed said.

The average annual rainfall is 230-280mm but even on 100mm, you're still in business, he said.

The Speeds say the biggest battle in beef production has always been the weather but outside that, they see keeping the live-ex trade going as a key challenge.

"The stopping of live-ex in 2011 was the single worst thing that's ever happened to this job," Mr Speed said.

"Live-ex is like having another abattoir in town. It secures competition. It's vital for northern producers."

Bob Speed graces the front cover of the 2020 NAB agribusiness calendar, a prestigious article that celebrates stories of resilience, intergenerational success and the ability to thrive in the face of adversity.

NAB agribusiness customer executive Neil Findlay said today's tough times were throwing multiple challenges at many agribusinesses.

Other beef producers featured include Raff Angus, King Island, Tasmania, and Victoria's Sher Wagyu.