Last remaining cow of the legendary tick resistant Adaptaur cattle

Despite being 16 years old, she has reared a calf this season. However, with a dwindling milk supply, it might be her last breeding season.

She belongs to Mick and Janet Thomas, who were co-operators in an Adaptaur research program run by CSIRO's Tropical Beef Centre during the 1990s.

"She's never had a tick in her life, it just proves that what they were doing was great research," Ms Thomas said.

Adaptaur cattle were tropically-adapted Bos taurus beef cattle, first developed in Australia at the National Cattle Breeding Station, 'Belmont' in the 1950s from a Hereford Shorthorn cross, HS for short.

At the time Herefords and Shorthorns dominated beef production in northern Australia, but Brahmans and Africanders were also being evaluated for the tropical environment.

Researchers started experimenting with no dipping and drenching after the '70s beef slump. They wanted to cross Brahmans and taurine breeds to build tick resistance while maintaining Bos Taurus traits.

In 1980, lead researcher Dr John Frisch started assessing dipping and drenching differences in three groups: Brahmans, a Brahman cross group, and a HS group. Results were compared with an untreated group.

Dr Chris O'Neill started working at the station around the time the experiment started.

"There was very little difference in the Brahmans, more of a difference in the Brahman cross, and a huge difference in the HS, so we started crossing the breeds and breeding from those animals that survived and were able to withstand the stress of living at Belmont," he said.

Dr O'Neill said they were manually counting ticks on the animals every 21 days.

"The Brahmans were carrying 15 to 20 ticks per side, Brahman cross 30 to 40 ticks per side, and HS were 300 or 400, so heavily invested," he said.

"And then by chance, one of the HS heifers placed in the control group had zero ticks during the count.

"We had this straight HS that was in this really heavy tick infestation and was as clean as a whistle.

"She initially had some ticks as a weaner, but when she was weaned she went totally resistant.

"That heifer was 79-546. Her sire and the dam were also a little bit resistant, but not that resistant.

"What we wanted to see firstly, was that was it just a freak one animal, or did she carry it onto the next generation? And she did, she passed on her resistance."

She was tested with vitals containing 20,000 tick larvae, with only one or two ticks maturing.

This line of cattle was later given the name Adaptaur. They were also selected for heat, worm and pink eye resistance.

Dr O'Neill said the reason for the tick resistance was that Adaptaur cattle exhibited a strong immune response to ticks due to their immediate grooming behaviour, which prevented ticks from attaching.

"Brahmans also groom, but not like that, they stand around an groom at the end of their grazing day."

In 1986 the first Adaptaurs were sold at an open auction.

The following year a number of co-operating producers from central and northern Queensland began evaluating Adaptaur bulls and their F1 Adaptaur progeny on-farm.

Janet and Mick Thomas were in the grazing business at the time and lived in the Boyne Valley.

Along with about 20 other co-operators, they were given three purebred Adaptaur bulls to help researchers assess performance.

They started comparing straight bred Brahman calves with the F1 calves, produced by Adaptaur bulls over Brahman cows.

"Over the 18 years we we're doing it, they were about 10 to 15pc better in growth rate than the straight bred Brahman, and 20pc better than the Brahman in fertility," Dr O'Neill said.

"When those F1s then went into the breeding season, they were highly fertile and tick resistant, well half of them were because it's a major gene.

"But if you kept culminating the resistant ones and got rid of the susceptible ones, you could have a whole herd of resistance.

"The Adaptaur bulls not only survived in these paddocks, but the calves they produce are highly productive and more productive than the straight-bred Brahmans."

A tick-free paddock was even observed in a herd at Glasshouse Mountain.

"He thought the whole herd had become resistant but what was happening is that the resistant animals within the herd were just hoovering up the tick larvae from the paddocks," Dr O'Neill said.

Mr O'Neill said in the late '90s, the CSIRO was going through severe funding shortfalls, especially for cattle, and their research came to a halt.

He said the CSIRO attempted the commercialise the Adaptaurs, but they weren't ready at that stage.

Belmont was put on the market for public auction.

"AgForce purchased Belmont because they wanted to do cattle research. But it was too late for the Adaptuars. They were dispersed and sold and the programs were shut down. We were made redundant," Dr O'Neill said.

"They sold the rights to using the Adaptaur to an American breeder... So industry didn't have access to the tick gene carrying Adaptuars."

The Thomas family got out of the cattle business in 2004 and sold off a lot of cattle, but they did kept a few cows from the tick resistant line. In 2014 they purchased their 404ha block in Biloela.

"I had my handful of cows and I decided to embark on my personal little program to see if I could move the tick resistant gene into an Angus line," Ms Thomas said.

"I am able to run my Angus cattle without any tickicides, pour-ons, injectables. They do get some ticks on them, I've not been able to duplicate the 100pc resistant cow unfortunately.

"I did retain straws of semen from an Adaptaur bull from years ago and I think the semen should come back over the 3/4 Angus heifers and cows. But this would need to be done by someone much younger than me," she said.