On a cattle property in central Queensland, Bobby Rowe is fighting an old enemy — one he fears may soon outsmart the tactics he deploys against it.
At Weir Park near Gogango, 65km south-west of Rockhampton, an outbreak of cattle ticks threatens his herd.
“You notice the cattle not looking as well as they should,” he said.
“You’ll lose production if you don’t do anything.”
Cattle ticks can be deadly to livestock by causing tick fever. (Landline)
For six years it looked like he was winning the battle, but in October he noticed an increase in the pea-sized blood-sucking insects on his cattle’s back legs and the loose skin on their neck.
For decades, the main line of defence has been pesticide treatments such as sprays, plunge dips, and injections.
But on another property he manages, Mr Rowe saw worrying signs the pest was growing resistant to chemical treatments.
“There are some steers there that we treated and 14 days later you wouldn’t think they’d been treated,” he said.
It is estimated that cattle ticks cost Australia’s beef industry more than $128 million a year. (ABC News: Megan Hughes)
A long history
Introduced in 1872 after 12 head of infested Brahman cattle from Indonesia escaped their yards in Darwin, cattle ticks thrived in the pastures of northern Australia.
“Where it’s hotter and wetter it’s a bit easier for the tick to survive,” the president of peak farming lobby group AgForce, Shane McCarthy, said.
Most tick species did not impact livestock, but he said the cattle tick could be devastating.
“The tick has a bacteria in it that affects the bloodstream… [it] makes them sick and kills them,” Mr McCarthy said.
He likened it to a David and Goliath battle but instead of a man defeating a giant, an insect the size of a thumbnail could take down an entire herd.
Graziers behind the tick line check for increased numbers of ticks on an animal’s back legs and neck. (Supplied)
Building a resistance
According to the University of Queensland, cattle ticks cost Australia’s beef industry more than $128 million a year.
For almost 20 years, Ala Tabor from the university’s Queensland Alliance for Agriculture and Food Innovation has been working to create a cattle tick vaccine to combat rising resistance to current treatments.
“It’s not like you can use them [chemicals] forever because they’ll stop working,” Dr Tabor said.
In 2010, a previous vaccine was discontinued after failing to gain widespread adoption among beef producers, as it required several administrations per year.
She said a single annual dose of her vaccine was designed to build the immune system of the cattle, making them less palatable to the ticks and interrupting the insects’ feeding and breeding cycle.
Already proven highly effective in early trials, Dr Tabor said the team was now trialling it on a larger scale to prove the concept in a commercial setting.
Dr Tabor has been working on a cattle tick vaccine for almost two decades. (Supplied: Queensland Alliance for Agriculture and Food Innovation)
Another weapon in the fight
Beyond just treating the ticks already on the cattle, at the University of Sydney researchers are looking to also treat the paddocks they infest.
Professor Joel Mackay is working on a pesticide that targets cattle ticks without hurting beneficial insects like dung beetles.
It is similar to products already used to target caterpillars and moths in cropping.
Dr Mackay says a multi-pronged approach is key to defeating pests. (Supplied: Joel Mackay)
“Proof of principle is already established and what we want to do is develop on that a lot further,” he said.
While still years away from commercial availability, he said it offered another weapon in the fight, one that could be deployed to tackle other similar pest problems.
“We’ve learned that in the control of most pests, a single strategy doesn’t usually give you 100 per cent success,” he said.
Holding the tick line
To manage cattle ticks in Queensland the state is split into two zones: tick-free and infested.
Outbreaks in the tick-free zone are not uncommon.
Recently ticks were detected at the saleyards in Roma, in southern Queensland, and have been traced back to nine properties, but the source of the outbreak is not yet known.
Mr McCarthy said industry and the government were working to eradicate the ticks from those properties.
Queensland Minister for Primary Industries Tony Perrett said at least 184 properties in the tick-free area were known to have infestations.
“If you’ve got resistance in your ticks to certain chemicals, you’ve got a real problem … I certainly hope that that’s not how they got there,” he said.
Farming on the infested side of the line, Mr Rowe said he kept numbers down by combining chemical treatments with pasture management — frequently moving cattle between paddocks to allow grasses to grow back healthier.
Weir Park runs around 800 head of cattle at Gogango, in central Queensland. (ABC News: Megan Hughes)
“[Ticks] lay eggs in the grass and then if there’s no livestock there for them to attach on yes, it’s got to reduce [them],” he said.
For cattle to be sold across the line into “clean country” they must be pre-treated, inspected, and declared tick-free, which cuts into profits for farmers like Mr Rowe.
Mr McCarthy said with the right management options, he believed eradication was feasible.
“Anything is possible, you just have to spend the money that’s got to be put in it.”
