WHEN Bool Lagoon producer John Mossop moved into shedding sheep there were probably a few people wondering what he was up to.
But 13 years on he has no regrets running an easy care Nudie flock with no shearing, crutching or lice treatment.
Through selecting for worm resistance he is also only drenching once a year in his 600mm rainfall area.
The biggest challenge for Mr Mossop has been lifting lambing percentages to somewhere near where he was used to in the composite flock he previously ran.
He has achieved this with genetics collaborating with sheep breeder and reproductive physiologist Colin Earl who at the same time was developing the Prolific White sheep, a shedding sheep with the Booroola gene.
"We had the shedding sheep and Colin was keen to get the gene into some shedding sheep and then we have transferred some genetics back and forwards for quite a few years," he said.
Where he was once struggling to achieve 120 per cent lambing percentages Mr Mossop says he is now achieving 140-150pc.
About half of the Mossop's 1400 Nudie ewes contain a copy of the Booroola gene and are consistently scanning about 60 per cent more foetuses than those without the gene.
'We could go higher if we really pushed it but to what level we want to go to I am not sure," he said.
"If you end up with two copies of the gene in every ewe you start to get extreme."
The scanning percentage boost has been confirmed in a trial on a mob of Prolific White-Nudies and Nudies without the Booroola gene. Both lines of ewes were 64kg at mating and in condition score 2.7.
The carriers scanned at 208pc while 140 non carriers had a 148pc scanning rate.
Importantly in the carriers there were 4pc dry ewes, 13pc single bearing ewes, 54pc scanned in lamb with twins and 29pc with triplets. The non gene carriers had 10pc drys, 37pc singles, 48pc twins and 5pc triplets.
"We have seen a 60pc increase in utero which seems to happen quite predictably no matter what you put the Booroola gene over," Mr Mossop said.
This higher scanning rate has translated into about 30pc higher lambing percentages and Mr Mossop still sees potential for this too be significantly higher.
These ewes have been lambing since June and so far they have only lost one ewe.
Mr Mossop's first foray into shedding sheep was the purchase of a mob of Dorpers from the Eyre Peninsula.
Within a couple of years they began having foot issues and he realised he needed sheep bred in a higher rainfall environment.
This led him to buying Nudie rams from western Vic seedstock producer John Keiller, which he has continued to do.
"There is not a lot of objective measurement in shedding breeders but he measures every trait you can think of," he said.
Mr Mossop has an elite flock of 100 Prolific White ewes he uses to breed his replacement rams.
As the popularity of shedding sheep has surged he has enjoyed outstanding prices for ewe lambs. The wether lambs which are finished on bean stubbles are also making good returns. They are sold on hooks at about 26kg dressed weight, largely to Australian Lamb Company.
"We have improved the growth rates (of the shedders) and while they are not up with the wool sheep I know we will get there," he said.
DEVELOPMENT OF PROLIFIC WHITE
IT has been a long road for Colin Earl to breed a shedding sheep with the Booroola gene which he first commenced working with while working as a reproductive scientist at Struan Research Centre in the 1990s.
He started with Dorper semen from Denis Russell's Genelink stud over his Multimeat sheep- a meat sheep composite he developed containing the gene.
Over subsequent generations he has DNA tested to ensure rams selected carry at least one copy of the gene and also have good worm resistance. He has only kept those ewes and rams which have been fully shedding and have good feet.
"The result is a medium maturity ewe which can scan 200 per cent lambs at condition score three," he said.
He says shedders will need a lift in reproductive rate to be efficient and while many maternal breeders are trying to find alternative genes they should not be overlooking the value of the Booroola gene.
In early years he acknowledged it was hard to predict their litter size but about 10 years ago he identified a ram which was more predictable in its expression of the Booroola gene. Producers can almost "dial up" the lambing percentages they want based on ewe nutrition.
"If you have a flock lambing at 150pc and put the gene in it will lamb at 210pc but if you want to lamb at 200pc you have to pull the scanning rate of your flock back a bit," he said.
"If you mate your flock 10 kilograms lighter you will drop it by 20pc."
Dr Earl believes Prolific Whites will have a strong place in the high rainfall areas and in the wheat-sheep zone of Australia for those producers wanting to lower their labour requirements.
"We need to do a trial to see how they go in the pastoral area and are working on selecting genes for non seasonality for people who want three lambings in two years," he said.
Dr Earl has already supplied rams to a few producers for evaluation, The results have confirmed that the gene is behaving exactly as predicted and lamb and ewe survival rates have been excellent.
More rams will be made available to commercial producers later this year.
