The 2020 Cobber Challenge will be the fifth year of celebrating Australia's hardest working dogs and this year the format has been shaken up to an All Stars versus Contenders competition.

In the past four years, 42 working dogs have been cheered on across Australia in the Challenge as the dogs demonstrated what it takes to be the most valuable team member on Australian farms.

Under this year's format, six competition favourites from previous years will compete against six new contenders.

The 2020 Cobber Challenge will run from 17 August to 6 September and entries close 26 June.

Kellie Savage, Cobber's marketing manager, said the Cobber Challenge provides hard data to prove what most Australian farmers already know; a good working dog can do the work of at least two or three people.

"In previous years, dogs have regularly clocked over 50km in a day, highlighting their contribution to the farm team," Savage said.

Each dog will be fitted with a GPS collar to track their distance, working duration and speed over a three-week period. Points are awarded, the dogs are ranked, and by the end of the challenge, a new Cobber champion will be crowned.

Each day of the competition, data is uploaded to the Cobber Challenge website so fans can follow the performance of individual dogs, as well as the best performing team.

South Australian farmer Peta Bauer won last year's challenge with Border Collie, Jed, who clocked a record 717km over the three weeks.

"I found competing in the 2019 Cobber Challenge with Jed very rewarding. It gave me a better insight to how much our dogs actually do in one day. And it gave me a new appreciation for Jed's dedication to work and his drive to please me," Bauer said.

"Jed had a week off after the Cobber Challenge before returning to help with lambing, crutching, shearing and calving. Unfortunately, Jed has had to have an unscheduled break after a run in with a heifer two weeks ago that saw him break his leg. He is out of action for about eight weeks," Bauer said.

As well as the glory of being a Cobber Champion and receiving a year's supply of Cobber Working Dog feed, the winner will receive $3000 to be spent on a working dog breeding program, training for a working dog or participation in working dog trials.

To nominate your working dog, fill out the nomination form at https://www.surveymonkey.com/r/2020cobberchallenge