Genomics – Are we there yet?

 

We are at the dawn of a genomic age, moving from genetic predictions that are based solely on pedigree and performance data to those that now include genomic data, information about the variation in an animal’s DNA and the individual genes it possesses.

Which breeds currently get genomic breeding values?

Signet deliver three mixed breed genetic evaluations

• Hill Sheep Evaluation – Six hill breeds already get genomic breeding values (Brecknock Hill Cheviot, Hardy Speckle, Eppynt Speckle, North Country Cheviot (Hill type), Scottish Blackface and Welsh Mountain)
• Maternal Evaluation – Not currently a genomic evaluation, but watch this space.
• Terminal Sire Evaluation – Genomic evaluation launched this month. The Suffolk, Hampshire Down and Charollais breeds became the first terminal sire breeds to get genomic breeding values with Signet and the first in the country to get them for abattoir traits.

Which breed has the most genotypes?

In the table below you can see the impact of the Welsh Hill Ram Scheme (led by HCC), which is now the Welsh Sheep Genetics Project (run by Farming Connect). Half of the genotypes that Signet use in routine evaluations belong to Welsh Mountain sheep.

Large numbers of Exlana and Lleyn genotypes have been uploaded in recent months, which means that genomic solutions for these two breeds will probably be produced in the next couple of years.

In 2024 alone nearly 30,000 Signet recorded lambs were genotyped, only eight years earlier we didn’t have a single genotype on file.

How can I get involved?

Breeders can get involved by genotyping their animals. The most important ones to start with will be the farm’s stock sires, as their genetics will be expressed in a high proportion of the flock.

Amongst Signet’s numerically largest breeds  many already have  a high proportion of the lamb crop produced by a sire that has been genotyped – or a sire that has been genotyped and has a genotyped sire himself.

In breeds like the Suffolk, Charollais and Hampshire Down over 90% of the current lamb crop are now produced by a genotyped sire. Don’t forget that semen can be genotyped too, so if you have semen in the tank belonging to older sires please get it genotyped.

Over the last 12 months, a number of Signet recorded flocks (in specific breeds) have been provided with the opportunity to get their females done – with funding provided by AHDB (England), HCC (Wales), QMS (Scotland) and AgriSearch (Northern Ireland). This funding has enabled breeds to start testing older stock ewes that have highly accurate EBVs and are thus important animals to have tested. All CT scanned lambs are now routinely genotyped for the same reason. Contact Signet@ahdb.org.uk if you think you might be eligible for funding.

How does genomic information support my breeding programme?

Genomic information has a variety of potential uses and breeders genotype their sheep for many different reasons.

• Sire / dam verification – important for forward thinking Breed Societies
• Reporting major genes, such as Scrapie, Myostatin and major fertility genes
• Increasing the accuracy of breeding values.
  • Genomic data adds massively to our knowledge of traits that are only expressed in one sex (like milk), expressed later in life (like longevity) and hard/expensive to measure (like methane or meat-eating quality)
• Increasing the robustness of genetic comparisons between flocks.

Genomics will augment the accuracy of the breeding values that Signet produce for well recorded sires, while introducing new information for previously unrecorded sheep that provides them with a fairer and more robust starting point when entering a genetic evaluation.

Ultimately those breeds that have genomic breeding values will get more accurate and more reliable breeding values, helping breeders to decide which animals to retain, measure or sell for pedigree breeding.