Pushing boundaries pays in prime lamb system but balance needed

Pursuit of meatiness


SA growers seek optimum balance between meat, wool and body size.

PREPARING FOR SALE: Kevin and Jacki Baker with newly-weaned 2020 drop lambs.

PREPARING FOR SALE: Kevin and Jacki Baker with newly-weaned 2020 drop lambs.

Pushing sheep enterprise productivity by optimising meat and wool returns - without necessarily increasing animal body size - is a future target for Avenue Range graziers Kevin and Jacki Baker.

The couple, whose son Mitchell started farming with them this year, run 2000 breeding ewes and 100 cattle on 1000 hectares in the small locality of 'Avenue Range' near Lucindale, in South Australia's south east.

About half of the ewe flock is mated to Gum Hill Merino rams for self-replacing breeders and wool production, and the remainder to Woolumbool Poll Dorset sires for crossbred lambs.

In recent years, the family has been pursuing genetic and management improvements to boost wool production.

But prime lambs have always been a part of the sheep system and will continue to be an integral focus of their business going forward.

Mr Baker said, as long-term Merino growers, the size of their sheep had been steadily increasing as they sought to produce more wool per head and per hectare.

He said this had positive spin-offs for lamb production, as ewes could carry lambs more easily, birth bigger lambs and were more robust to rear their progeny and regain condition quickly for the next mating.

But in the quest for higher wool cuts, sheep body size had increased and Mr Baker said this had now almost reached a 'tipping point'.

"We are close to an optimum size where sheep can be handled safely and efficiently during husbandry practices and, especially, when shearing," he said.

"Sheep body size is a real issue, as it starts to present occupational health and safety risks that need to be managed - and it potentially deters those who might be interested in becoming shearers."

Mr Baker said in the past two decades there had been a lot of information about sheep types, much better access to new breeding technologies and a mindset that 'bigger is better'.

"In that time we have gone from ewes that weigh about 50 kilograms to now about 80kg," he said.

"Animals this size are hard work to yard and handle, for shearers in particular, and I don't think it can go much further.

"Some shearers are already commenting on the physical strain they endure in getting sheep from the pen to the board and into position.

DUAL INCOME: Mitchell Baker and partner Micaela Lock inspect some of the family's annual woolclip.

DUAL INCOME: Mitchell Baker and partner Micaela Lock inspect some of the family's annual woolclip.

"They describe it as like trying to achieve a personal best 'clean and jerk' if you were a weightlifter.

"I think the industry in general might have reached the point now where we could consider holding the size of our sheep, but seek alternative tactics to grow more meat and improve wool quality to keep returns trending upwards.

"There are many strategies we can use and that can lead to more efficient and profitable sheep enterprises."

In their own sheep system, the Bakers join about 500 Merino ewes and up to 400 multi-meat-Merino ewes to Poll Dorset rams annually in December and the remainder to Merino sires three weeks later.

Lambing occurs in May for crossbreds (and June for Merinos), aiming for a spring turn-off as suckers. Marking percentages average around 150 per cent for the ewes mated to crossbreds and 120pc for the straight Merinos.

This fits with the annual pasture cycle, as lambing and lactating ewes and their progeny are able to take advantage of optimum paddock feed on offer at the end of winter and into the spring months.

Ewes and lambs are grazed during winter and spring on improved pastures established on heavy black soil types, and on lucerne that is sown in sandy, higher ground on the property as an alternative high-value feed source.

From the pure Merino flock, the Bakers retain about 330 ewe lambs for future breeding and wool with the remainder sold as one and a half year olds after their second shearing.

The aim for Poll Dorset-Merino crossbred progeny is to achieve industry best-practice winter growth rates of about 250 grams per head per day.

This sets the lambs up for sale from October onwards at an average liveweight of about 50-55kg - which provides processors with a carcase weight of about 22-24kg.

At the start of weaning in September 2020, about 2pc of the Baker's crossbred lambs hit liveweights of 50kg or more and these will produce carcases weighing more than 25kg.

"We don't necessarily focus on daily weight gains, but have a firm target for our prime lambs to be reaching 50-55kg by mid-October and November," Mr Baker said.

"We aim to have at least 50pc sold before December, when the feed turns."

HAPPY DAYS: Ewes and lambs are grazed on improved pastures during winter and spring months.

HAPPY DAYS: Ewes and lambs are grazed on improved pastures during winter and spring months.

The Bakers mostly supply straight to processors and are JBSFA lamb producers. They sell into Bordertown, which is their closest processing facility - and to Midfield at Warrnambool when the price is right.

They shear the lambs early November to avoid potential wool contamination from grass seeds during summer and before the next shearing.

Using grass-free lucerne pastures to raise prime and Merino lambs also helps to manage this risk.

The family sources Poll Dorset sires from Phil Clothier's Woolumbool stud, which - for many years - has been objectively measuring for and advancing in key profit-driving traits of high weaning and post-weaning weights and good muscling.

This focus is paying-off in the paddock for the Baker family, which finds its lambs are quick to get to selling size - underpinning long-term trend increases in meat production output per hectare.

Mr Baker said Woolumbool genetics were 'gold standard' and he also chose to use the stud based on its aim to breed sheep with moderate mature bodyweights.

He said, aside from handling issues, bigger sheep tended to be late-maturing and this meant they required more feed when they were at a mature weight while not rearing a lamb.

"That is just not efficient in our environment," he said.

The Bakers select their Woolumbool Poll Dorset sires based on Lambplan Australian Sheep Breeding Values (ASBVs) for positive weaning weight, 100 and 200-day growth, eye muscle depth and take into consideration the worm resistance data that Phil supplies - as well as assessing the visual confirmation of rams.

Lambplan analyses indicate rams with positive ASBVs for weaning and post-weaning weight will produce lambs that grow faster to weaning or target selling date and be 0.4kg and 1.25kg heavier (on average) than a ram with a zero ASBV for these two key traits respectively.

Those rams with a positive ASBV for eye muscle depth will tend to throw lambs with a higher lean meat yield and produce carcases with an average eye muscle that is 0.2mm deeper than it is in progeny from a ram with a zero for this trait.

"We find the Woolumbool rams are 'true to type' for these traits and this feeds into our own breeding objectives that target optimum lamb or wool production," Mr Baker said.

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