As our Olympic athletes faced their first day of competition in Rio, the country's top 120 working dogs slogged it out in West Wyalong, New South Wales at the 2016 Australian Yard Dog Championships.

The stock dogs came from all over the country for the job, to see which could round up and move a pack of testy merino sheep the most efficiently, on a course that mimics everyday jobs on the farm.

The host state will celebrate its 30-year anniversary with the sport in October.

But it was a Victorian breeder who claimed the title, taking his tally of national championships to five.

"A lot of it comes back to finding a dog that you like and showing a bit of trust in that dog," said Joe Spicer, from Glenthompson in western Victoria, before claiming the day.

"That bond where you have a fair idea what the dog is going to do and the dog knows you well and you can almost read each others' minds."

Cody Whitby, 13, competes in the juniors' league at the West Wyalong yard dog trials. ( ABC Rural: Peta Doherty )

One of his other kelpies, the 2015 champion Bruce, was just the second dog to have claimed two titles in the 34-year history of the sport.

But the title was a first for young kelpie Basil.

Mr Spicer said the West Wyalong merinos had showed some resistance.

"Very challenging, which is the way we want it. It does sort out the better dogs, there's no doubt about that," he said.

"At the end of the day the dogs that do well are the ones you can take home and be proud of, and do any job on any property with."

Sport transformed since early days

Kevin Howell said the sport had transformed since he first competed, shortly after the NSW Yard Dog Association formed 30 years ago.

"They were pretty lackadaisical in the early days," the kelpie breeder from Eugowra in the NSW central west said of the days when trials were held on-farm or at a local show.

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"As long as the dog got the sheep in the yard everyone was happy. But now we have to look after the dog and look after the stock, and it's called low stress handling."

Yard dog trials started a few years before the sport arrived in NSW.

A group of stockmen from Tasmania wanted to show the public how they worked their dogs in a real life setting.

The emphasis on animal welfare has changed the sport for the better, making it a model for best practice stock handling, Mr Howell said.

The Australian Yard Dog Championship at West Wyalong. ( ABC Rural: Peta Doherty )

"When the public come along they can learn ... if there's jackaroos or farmers watching, they can learn the better way of handling stock," he said.

Mr Howell said challenging obstacles like platforms that mimicked truck-trailers and larger yard areas had improved the contestants, especially the size of the pick-up area, which was originally about one eighth the size of today's yard.

"That's improved the quality of the dogs out of sight in that time," he said.

"The dogs that win, people breed from, so that's how it has improved the quality of the dogs."

It is not just the dogs that have improved — the sport is also attracting bigger crowds thanks to better seating, planning, accommodation options, and not least a good commentator.

William Cox has been working with dogs and sheep since he was 4 years old. ( ABC Rural: Peta Doherty )

"Having a good commentator gets people coming along and keeps them coming," Mr Howell said.

"They become judges after a while because he tells them what's right and what's wrong.

"In the early days the commentators were saying a bit much and more or less coaching the person out on the arena."

Daughter of man who introduced sport competes

John Rosten from Armidale is the man who brought the sport to NSW.

Competing in the 2016 national championship was his daughter Jenny Cox and grandson William Cox.

"It's a real honour that Dad's been a real driving force, especially in the north of the state," said Ms Cox, who stands out with her border collies in a sport dominated by males and kelpie dogs.

William Cox, 14, at a yard dog trial in West Wyalong. ( ABC Rural: Peta Doherty )

"It's a real honour that it's still going 30 years later, and as you can see today the standard is really big and there's just so many people competing in the sport, both young and old.

"I'm very pleased to be able to show the collies off for what they can do, and always flying the flag for the females as well."