Are sheep getting too big for shearers?

And it's making the industry a less appealing option for those considering a career in it, which could cause problems down the track in regards to the future availability of shearers.

Phil Rourke has been a shearer for over 30 years and currently works for a contracting business in north-east Victoria.

During the busy season when he's working five days a week, each morning when he wakes up, he's unable to feel his arms from his shoulders to his fingertips.

And he said it was all to do with how big sheep had got in the last 10-15 years.

"When I started shearing in the late '80s, you had to be careful with Merino ewes so you didn't break their front legs while handling them, but now, the average Merino ewe is so heavy and strong that you can't even tip it without busting your guts," he said.

"Instead you have to grab it by the legs and flip it like a ram, and then you have to drag its 80-90-kilogram body out onto the board and try to get its front leg back into position; kind of like trying to achieve a personal best clean and jerk if you were a weightlifter."

Mr Rourke said physical problems were apparent in every shearer he knew.

"It's the sheep that will end my career," he said.

"If a young person was to ask me if I thought being a shearer was a good idea, I'd say you'd have to be crazy to do it.

"Nobody else in any other industry has to go through the physical strain we do or deal with manhandling single-handedly such huge animals."

He said it led to mental health issues in shearers too.

"You're getting the daylights kicked out of you all day, and by the end of it you're so tired," he said.

"And then you've got to get up the next day and do it all over again."

He wanted wool growers to take more accountability for the size of their sheep.

"Sheep breeding is unregulated, they are not limited by any regulation as to size and weight and the goal is to breed them as big as possible, cut more wool, bigger carcase weights and on and on and we have to wear it, it's not their problem, it's our problem," he said.

"I have encountered a few that have decided to downsize, but not because of the problems their shearers are having, because of the problems they're having with them in the yards.

"The yards just can't cope with the size of the sheep and the farmers and labourers are getting hurt."

Shearing Contractors Association of Australia Shearer Woolhandler Training chief executive Glenn Haynes said the size of sheep and the difficulty that caused shearers was the biggest reason young people gave up a career in the industry after formal training.

"Normally we get a 30 per cent retention rate of shearers after training them," Mr Haynes said.

"The majority that go into the industry would stay but if we trained 100 and 30 stayed, you'd probably get another five or six that left within 12 months.

"Some even leave within a couple of weeks."

And he attributed that to the young shearers realising exactly how hard the job was.

"When you're learning, there's someone there to help you, but now, you're out on your own and you've got to drag those sheep by yourself," he said.

"It sorts those that really want to do it against those that don't have the same drive."

Shearer Woolhandler Training instructor Tom Kelly said wool growers should do all they could to make shearers' jobs easier for them.

Mr Kelly said shed design played a big part.

"A lot of sheep have outgrown their sheds, whether it's the yards they're in or the shoots that you put them down," he said.

"What was built all those decades ago has become too small for the sheep they're breeding today, and that poses battles trying to get sheep through things."

He didn't expect wool growers to rush out and build a brand new shearing shed, but said there were small improvements that could be made that would have a huge difference.

"You'd be surprised what you can do with half a day and some carpentry tools," he said.

"A lot of sheds can be improved without having to go to ridiculous expenses."

He also encouraged wool growers to empty out their sheep for as long as possible prior to shearing to make the process smoother.

"If you're able to empty out their food and water from the day, they'll settle down a bit more," he said.

"Sheep enjoy the process a lot more if they're emptied out, they don't have the pressure on their belly."

He said Australia should follow New Zealand's lead in offering guidelines for the amount of time sheep should be off feed before shearing.

In New Zealand, WorkSafe guidelines say a ewe that is not pregnant or lactating, as well as adult male sheep, should spend no less than 20 hours off feed prior to shearing and no less than 12 hours without water.

They also have guidelines for ewes at different stages of pregnancy.

Mr Kelly said there were techniques that made shearing easier on larger-framed sheep and these were taught at shearing courses across the country, but it was "still the hardest job you'll ever learn".

"There's no denying that sheep are getting bigger but we've got to try and positively work our way through it together," he said.