Ovine Observer

Property: ‘Brookvale’, 20km north west of Kojonup
Property size: 2250ha (owned and leased)
Owners:  Lynley Anderson (owner/manager) and parents Alan and Wendy
Average annual rainfall: 460ml
Stock: 4500-5000 head Merino ewes, 120 Poll Dorset ewes, wethers are sold as weaners
Stocking rate: 11-12 dry sheep equivalents (DSE)
Crop: 850ha canola, barley, oats, wheat
Pasture:  900ha improved pasture including fodder crops and perennial pastures

A 40 year commitment to objective measurement over two generations has led to high performance sheep across a range of wool, meat and other traits.

Kojonup producer Lynley Anderson has followed in father Alan’s footsteps by embracing Australian Sheep Breeding Values (ASBVs) to determine an animal’s true breeding value, based on pedigree and performance recordings.

Alan was a pioneer of objective measurement in the 1960s, selecting rams based on clean fleece weight, fibre diameter and body weight at a time when selection by visual assessment was the norm.

ASBV adoption

By the turn of the millennium, Lynley had come on board the operation.

Despite the advances in key traits across their flock, the Andersons became concerned their selection strategy was “discounting” the potential of progeny from maiden ewes and twin bearers because they were lighter and cut less.

In 2002 the Andersons jumped at the chance to contribute to a pilot project for Sheep Genetics Australia in the development of genetic breeding values.

“We could see great advantages in using genetics to select animals because it removed the environmental influences on an animal’s appearance and its objective measurements.” Ms Anderson said.

 “We would be able to select the best rams regardless of the circumstances of their birth or upbringing.

“It was also a great opportunity to be able to breed for other traits like worm resistance, fast early growth and a meatier carcass which would enable us to turn off our wether lambs earlier.”

Worm resistant sheep

At this time the Andersons decided to focus their breeding objective on producing low maintenance sheep and started selecting for sheep with low faecal worm egg counts.

“It was clear that the effectiveness of drenches was fast declining and that any new drenches were going to be expensive so we wanted to do away with drenching altogether,” Ms Anderson said.

To assist the process, the Andersons sourced semen from DAFWA’s Rylington Merino Flock, which was dedicated to breeding sheep with resistance to worms.

The Andersons now have some of the most worm resistant sheep in the country, with many ranking in the top 1 per cent in the Merinoselect database for this trait. 

The Andersons haven’t drenched their adult sheep for six years and only about 10 per cent of weaners now require a drench.

Selecting for worm resistance is one trait Ms Anderson does not compromise on.

“An ASBV of minus fifty is my benchmark,” she said. “When selecting rams there is always a compromise, as there is no such thing as a perfect ram, however, I won’t compromise on the worm egg count as it can limit the overall performance of the animal.”

Figures

This discipline is at the heart of Ms Anderson’s flock breeding objective: to produce robust, productive, low maintenance and fertile sheep.

The objective is achieved through a nucleus flock of 450-500 Merino ewes and 120 Poll Dorset ewes.

More than 50 visual and objective traits are measured and recorded on each animal from birth to hogget age to refine selection and provide accurate ASBVs for each sheep.

Objective measurements include clean fleece weight, fibre diameter, coefficient of fibre diameter, comfort factor, staple strength, worm egg count, eye muscle depth, carcass fat, birth weight and growth rates.

The visual traits assessed include body and breech wrinkle, wool colour, face cover, dags and temperament.

Merinoselect records (see above) from 2003-13 show the flock’s clean fleece weight has increased 9 per cent per head, while maintaining fibre diameter and decreasing fibre diameter coefficient of variation.

Of the meat traits, the average yearling weight has improved by 4kg and eye muscle depth has improved by 5 millimetres, making the flock genetically more muscular and fatter and more robust.

The average dual purpose index value of the flock is now 170 units, which is nearly 32 index points higher than the Merino ram breeding industry, and about 34 index points higher than it was 10 years ago.

Record benefit

Lambs are tagged at birth in order to record their pedigree, birth weight, birth date and whether they are born singles or twins.

While lambing is a busy time, for Ms Anderson, a former midwife, it is a labour of love.

“It is a great job,” she said. “Although I do wish it took a little less time but I enjoy seeing the ewes being so protective of their lambs.”

The Anderson’s rams now regularly feature in the top Merinoselect dual purpose plus index rankings, although Ms Anderson said they were always striving for improvement.

“It’s about making progress in the profitability traits for wool, meat and fertility, but still keeping a balanced animal that is easy care and worm resistant, ” she said.

“Using ASBVs takes the guess work out of knowing how your progeny will perform and gives you the confidence that your breeding objective is always progressing forwards.”

While the Andersons found it difficult to quantify the financial gain of using ASBVs, Ms Anderson said the benefit was undeniable.

“As a result we’re running more stock, our lambing percentage has increased, we rarely drench and sheep maintain condition much more easily,” Ms Anderson said.

Sire evaluation trial

Last year the Andersons contributed a ram to the Department of Agriculture and Food’s renewed Yardstick sire evaluation trial.

A total of 11 rams from Western Australia Merino studs and another two from the Eastern States are participating in the benchmarking initiative, supported by the Federation of Performance Sheep Breeders (WA) and consultants Icon Agriculture.

Department development officer Meghan Cornelius is coordinating the trial, as part of her role to raise awareness and adoption of ASBVs in Western Australia.

“ASBVs can be very confusing to the uninitiated, as there is so much information to take into account,” Ms Cornelius said.

“We have held workshops to assist ram buyers with using ASBVs and workshops for breeders to assist with data quality, data management and specific software programs.

"Department staff can also work with individual producers to assist them to better understand the system and how to use it.”

The two year trial, supported by industry and the Royalties for Regions-funded Sheep Industry Business Innovation project, with assistance from Australian Wool Innovation, is expected to yield data that will be accessible to producers later in 2016.

Sheep genetics research

Ms Cornelius also works closely with senior research officer Johan Greeff to provide producers with an insight into new ASBV traits.

Dr Greeff works with the former national Information Nucleus Flock, now known as the Genetic Resource Flock, as part of a national Sheep Cooperative Research Centre project funded by Meat and Livestock Australia to refine meat quality and sheep wellbeing traits.

“While these traits are heritable and can be measured, they are comprised of multiple traits that are correlated to other traits,” he said.

“The challenge is to improve growth rates without compromising on meat quality.”

The project is working towards refining ASBVs for meat tenderness, growth rates, fat content and weight changes, while other research is investigating immunological resilience and performance.