Southern farmer
Pepperton driving genetic selection to boost profit drivers for producers and processors

WITH the industry shift to lamb brands focused on eating quality, one Victorian stud is trending well above breed average for intramuscular fat, shearforce (tenderness), muscle and weaning weight.

Fifth generation farmer Roger Trewick and his wife Dianne, of Elmore, have been breeding Poll Dorsets under their prefix Pepperton since 1994 and were early adopters of LAMBPLAN performance recording, concentrating on growth, muscling, and moderate fat levels.

Adding White Suffolks in 2004, Pepperton produces each year around 200 rams grazed on dryland lucerne with minimal grain feeding during dry times.

Data is collected by seven months of age on all rams, and they consistently test high for muscling and growth with moderate fat and lower birthweights.

Roger and Dianne’s son Kurtis and his partner Tara Gibbons have recently joined the management team at Pepperton.

The family was awarded a five star data quality score by genetic evaluation service Sheep Genetics in July for their dedication to collecting and submitting high quality data.

“The heavy focus on genetics has been instrumental in producing rams with traits the market is demanding such as high muscling, fast growth and low to moderate birth weight,” Dianne said.

“The top index ram lambs from each of the sires used in the AI program are DNA tested for intramuscular fat, shearforce, lean meat yield and dressing percentage resulting in excellent lamb eating quality indexes.”

In recent years Pepperton has made consistent genetic advancements towards improving the key profit drivers for their Poll Dorset and White Suffolk rams.

Post weaning weight and post weaning eye muscle depth are both trending above the breed average and Australian Sheep Breeding Values analysis target.

Tara said the drive to higher post weaning weights had resulted in earlier maturity, higher weights, and a faster turn-off period for sucker lambs to market for producers.

In the past decade, rapid genetic gain has been made in intramuscular fat (IMF) or marbling, trending from -0.85 in 2014 to -0.27 in 2023 in the Poll Dorsets, well above the breed average and analysis target.

In White Suffolks it rose from -0.75 to -0.04 in the same period and is well above the breed average.

Pepperton began DNA testing rams for IMF in 2017 and sources leading industry sires for the trait to increase marbling and eating quality in carcases.

During the past decade shearforce has also been rapidly decreasing and lamb eating quality increasing resulting in more tender lamb cuts and a better consumer eating experience.

Pepperton runs 400 stud ewes, achieving an 82 per cent conception rate to AI this year.