Days to Slaughter EBV – The most important indicator of growth?

Over the last 8 years AHDB have collected a wealth of abattoir data through RamCompare, with over 50,000 abattoir records supplied for lambs produced as part of this progeny test.

In November the Signet team will meet with breeders to explain how this information is going to change our breeding programmes.

For 12 months, breeding values for abattoir traits have been produced as a sub-set of information which has sat alongside existing traits like Scan Weight and Muscle Depth on the Signet website.

However, new research by Samir id-Lahoucine at SRUC will now be used to help us make better use of this information. Samir has calculated the genetic relationships that exist between those traits that we measure in pedigree flocks and those traits that are economically important to commercial farmers, namely days to slaughter, carcase weight and carcase conformation.

The strength of these genetic relationships are summarised as follows.

 

What does this mean for sheep producers?

Firstly, it is confirmation that our current direction of travel within our breeding programme is working, with selection for growth characteristics having a big impact on finishing times and AHDB’s investment in ultrasound and CT scanning services leading to marked improvements in carcase quality.

More importantly, by fitting these genetic relationships into Signet’s genetic evaluations in the we will be able to produce more accurate breeding values for abattoir traits, which may prove far more informative for commercial ram buyers.

Over the coming months, Signet will be looking to introduce these changes into the National Terminal Sire Evaluation and working with AGBU (the Australian Genetics Breeding Unit) to develop new breeding indexes (both economic and environmental) to capitalise on this new information

 

Example: The Impact on Weight Recording on Days to Slaughter

Here we can see that over the last 10-15 years, genetic selection in pedigree flocks to enhance growth rate has generated sheep with the genetic potential to reduce finishing times by about a week. In many individual flocks, gains have been even greater.

For the last 40 years we have told producers to select rams with high  Scan Weight EBVs to reduce finishing times, in the future our message will be simpler; select rams with superior EBVs for Days to Slaughter.