New biological wool harvesting research underway

Researchers at the University of Adelaide are confident they can provide an alternative method to conventional wool harvesting, with the early results of an injectable treatment for sheep showing signs of promise.

Australian Wool Innovation is funding the research into a new opportunity for biological wool harvesting that generates a weakened zone at the base of the wool fibre but enables the fleece to stay on the sheep until the wool can be mechanically removed.

Chief researcher Professor Phil Hynd of the University of Adelaide said the project took a biological approach that was different to the 1990s, CSIRO-developed Bioclip.

“Previous attempts at biological wool harvesting concentrated on temporarily stopping wool growth, which resulted in fleece shedding,” Dr Hynd said.

“In contrast, the new approach is aimed at creating a weakened zone of wool next to the sheep’s skin, which enables the fleece to stay on the sheep for several weeks.

“Wool will continue to grow beneath the weak point, so as to protect the sheep from hypothermia and sunburn after the fleece above the weak point is harvested.”

He said producers could harvest the wool above that weak point at a convenient time from between two to 10 weeks after treatment.

A small AWI-funded trial has already been undertaken in which the fleece did not fall off in the paddock under normal grazing conditions for up to 10 weeks after the treatment was administered.

Work is being undertaken to determine whether the treatment works on cross-bred and composite sheep as well as Merino sheep.

The new project will look at administering the treatment via an injection, rather than via feeding where there is the potential problem of ‘shy feeders’ not receiving a sufficient dose, and also differences in gut function between sheep.

The wool fibres are weakened to the extent that a removal device will break the fibre at the weak point and remove the fleece without the need for cutting equipment.

While AWI will seek proposals to develop mechanical/automated solutions to harvest weakened wool, the University of Adelaide is also looking at developing a device.

“Our engineers came up with a very simple hand-held device that has a spinning drum with little fingers on it that just break the fibres at the weak point and the sheep doesn’t feel anything,” Dr Hynd said.

The device can be operated by unskilled labour by running it at high speed across the sheep and the wool just peels off in front of the device.

It could also be possible to mount a vacuum system on the front of the device which will then suck the wool off away from the sheep.

“The real breakthrough would be automating the process so that wool can be harvested very quickly from large numbers of sheep in a high throughput system with very low labour input,” Dr Hynd said.

He said the researchers understood the urgency of the wool industry’s need for an alternative to conventional shearing and they were “working flat out to provide one”.

“We’ve made some big steps and I can say to growers that we’re confident that this is a good approach, we’re confident that we can make a weakened zone in the wool and we’re confident that we can get it off without a comb and cutter,” he said.

He said that by the end of 2024, researchers wanted to be able prove that the system worked, although once it was in a prototype field demonstration stage they would have to work through body weight types, different environments, sheep types, and check it had no effect on pregnant sheep or general health.

AWI chairman Jock Laurie said the project was timely and had the potential to be a game-changer for wool harvesting.

“It is critically important for the industry because we need to provide growers with new harvesting options,” Mr Laurie said.

“Times of pressure in industries drive change and that is exactly where we are with the wool industry right now.”