By Dr Emma McGowan, Genetics Specialist, Quality Meat Scotland (QMS)
A landmark 35‑year breeding initiative is reshaping expectations for hill sheep productivity, with new data showing unprecedented gains in growth, maternal performance and overall flock output across Scottish Blackface enterprises.
Signet’s longest‑running performance recording programme, dating back to 1990, has now assessed nearly 12,000 homebred sheep and progeny‑tested 260 rams, generating one of the most comprehensive datasets in UK hill sheep breeding. The genetic progress has been so profound that a sire ranked in the top 1% of the flock in 2005 would sit in the bottom 1% today.
Breeding for modern hill systems
Long‑term selection for lamb growth rates, mothering ability and milk production has yielded exceptional improvements. Since 1990, average lamb weights have risen by 175g per year for singles and 200g per year for twins, equating to an extra 6–7kg per lamb today.
Recent analysis comparing the top and bottom 25% of ewes in 2025 highlights the real‑world impact:
This weight differential represents a major uplift in total flock output without increasing ewe numbers, land use or inputs
Queensberry Estate: Proving genomics can accelerate progress
While the original programme demonstrates the power of long‑term recording, the Queensberry Estate flock is proving that genomic technology can compress decades of progress into a few seasons.
Now in only their second year of recording, the estate uses full lamb weight records and DNA‑based parentage assignment to build accurate maternal breeding values across their April‑lambing Scottish Blackface flock.
Despite the early stage of the programme, genetic differences are already striking:
The data reinforces a key takeaway for hill systems: maternal genetics drive lifetime flock profitability.
On the Ground: Farmers see the benefits first hand
Hill producer Bobby Lennox, speaking with Dr Emma McGowan, Genetics Specialist at Quality Meat Scotland, emphasised that sustainable progress hinges on selecting the right animals for the environment.
His breeding programme prioritises:
These traits, he notes, are the backbone of Blackface performance on challenging upland ground – and the genetic results now emerging across Scotland underline the importance of capturing and selecting for them.
A blueprint for the future of hill flocks
Together, these two case studies show that whether through decades of structured recording or the rapid adoption of genomic tools, the message is clear: genetics are transforming hill sheep production.
Higher‑merit ewes are rearing significantly heavier lambs with no increase in flock size, offering a route to improved efficiency, sustainability and profitability across Scotland’s uplands.
Key Takeaways