A VISION of robotic shearing machines removing fleeces from sheep treated with a bioharvesting protein was floated with producers at the 2023 BestWool/BestLamb Conference in Bendigo yesterday.
But University of Adelaide professor Phil Hynd said the novel wool bioharvesting method, using a corn protein to weaken wool fibres, has worked consistently on Merinos, but not crossbred and composite sheep.
The protein weakens growing wool fibres to a tensile strength of about 13 Newtons/kilotex, and potentially lower, enabling harvesting with a plucking device that is still being developed.
He outlined a vision of wool being harvested by a hand-held or automated device under development that sucks it up for delivery to a classing table “all in one go”.
“That’s the plan, that’s the idea.”
He could envision a truck backing up to a sheep yard for wool harvesting negating the need for the traditional shearing shed.
“Yep, that’s probably where I might see it (going).”
Prof. Hynd said he is working with defence industry engineers talking about using sensors in robotics that could detect follicles that were not fully weakened and stop harvesting in a nano-second to avoid skin damage.
“That’s the sort of level that they are talking about.”
Professor Hynd said the bioharvesting agent would be delivered by injection rather than drenching or feeding. Not enough feedback had been sought from wool processors, but he could not see there would be any negative effects on skin value.
He said trials has shown no evidence of wool falling off in pastures for up to 10 weeks, enabling harvest at a producer’s convenience.
Prof Hynd said bioharvested wool would have textile benefits, being finer at either end of the staple, and with no second cuts and more uniform length.
He said a regrown fleece after the first bioharvesting would have a tip and base that is about four microns finer than the wool along the staple length, having a beneficial tactile effect on the final apparel product.
Will it work on crossbreds?
The research is showing that the method is probably not going to work on mixed breeds that don’t have a lot of Merino blood in them, Prof. Hynd said.
“I think it is going to depend on how much Merino you’ve got in your composites … and we still don’t know the answer to that.”
Prof. Hynd said “from a theoretical basis, this product works on follicles that are growing at the time of we treat.”
“So if a follicle is resting — it is just sitting in the skin in the resting phase — it won’t be affected, because the biochemistry is not working in that follicle.
“So theoretically, it will depend on what proportion of the follicles are in the growing phase and that depends on what proportion of the genotype is Merino,” he said.
A trial had been done with some pure White Suffolks and some crossbreds – Border Leicester-Merinos.
The treatment had no effect on the White Suffolks “even though they ate the most of the product”, and it worked on four of the crossbreds “better than the Merinos”, but it didn’t work in one of the first crosses.
“So we are at a point at the moment that we can’t answer the question (Will it work in crossbreds?).”
But he said when sufficient amount of the product became available then further work could be done relating treatments to genomics and Merino DNA.
Professor Hynd told Sheep Central the growth phase of wool is called anagen and is effectively what all Merino wool follicles are in 100 percent of the time and for the entire life span of the sheep — a result of selection over centuries for high fleece weights. He said hairy sheep breeds, like all the cleanskins, shed their fleeces seasonally, because the follicles simultaneously enter a resting phase called telogen and then a shedding phase called exogen.
“This occurs in a wave across the body with waves of shedding starting on the belly and moving across the body.
“Crossbreds are somewhere in-between with a proportion of follicles in the resting phase, some in shedding phase and others still actively growing,” he said.
“The proportion of the follicles that are in the resting and shedding phases in crossbreds will depend on what proportion of Merino genetics are in the cross.”
He said his project’s technology only works on actively-growing follicles, because it interrupts the biochemical events in growing fibres that make them harden.
“Resting or shedding fibres will not be affected.
“So we are unsure what effect our technology will have on crossbreds and composites because it depends on their Merino genetic makeups,” Prof. Hynd said.
“The growing fibres will be weakened, but the resting fibres will not.
“Whether they can be defleeced after our treatment then depends on how strongly they are held in the follicle,” he said.
“We don’t know this, so can’t predict if it will work sufficiently well to give producers with crossbred sheep an option to easily get rid of their wool.”
Treatment is effective on all Merino sheep classes
However, the treatment is effective in all classes of Merino sheep – lambs, hoggets, ewes and rams, with no negative effect on health, reproduction or meat quality so far. He said it will have to be cheap, ideally under $5/dose, but the cost question could not be answered at this stage.
“Our aim is to make it cheaper than shearing.
“There are no combs and cutters, there are no OH&S issues for the operator,” he said.
“You don’t have to straighten the wool out.”
Bioharvesting could be a high throughput system
Prof Hynd said the researchers are looking at a high throughput system.
“That’s well and truly down the track and I don’t want to overpromise, but if this works at a really basic level, I can’t see any reason in my long-term vision of how industries have gone ….. I can’t see why we couldn’t get to a point where we had sheep coming along a conveyor belt – a VE type thing – the machine directing the sheep, and it would be a robot-type machine” for wool harvesting.
“But it doesn’t have to be as clever as a robot machine using a comb and cutter.”
He said engineers have already come up with some 3-D printed models that are being tested and refined.
“I would get excited about a wool industry becoming high throughput shearing with wool harvesting with almost no people involved.
He shared his vision of wool being sucked off sheep and taken away on a conveyor belt to be sorted via video analysis into oddment and fleece lines, even on the basis of micron.
He said stakeholders should get excited about revolutionizing the industry, because the potential is there.
Prof Hynd said the research has shown that Merino fleece wool can be weakened, but it stays on in the paddock and can be removed by a single plucking machine with non-skilled labour.
“We’ve got the right target, I’m certain of that.”
Australian Wool Innovation is funding Prof Hynd’s research, but he said a Federal Government scheme that helps accelerate high potential commercial research had jumped the project “to the top of the queue” to refine the system’s “bullet” or delivery system.
He said development would involve large-scale on-farm trials across regions with different sheep types and wool qualities, and APVMA approval.
“It’s not going to be here in three years’ time, I don’t think, but it’s running pretty quick.”
Click here for information on the bioharvesting project in an AWI update.
The BestWool/BestLamb program is a partnership between AWI and Agriculture Victoria.