MLC research to develop better lean sheep index
By Hannah Velten
USE of the 13-year-old lean growth index for terminal sire sheep breeds may be a proven way to increase profits, but producer uptake of the science is limited.
In response, research by the MLC and SAC is aiming to develop a second generation of indices, based on likely future market needs for sheep meat and use of new technology.
Geoff Simm, head of SACs breeding and genetics, says the lean growth index was designed to increase the weight of lean at a certain age, while limiting fat levels. Use of high index rams results in crossbred lambs with improved carcass composition at commercial slaughter weight – 16-21kg – increasing producer returns, he adds. "Every high index ram leaves behind progeny worth an extra £600 profit over his lifetime, but only 16% of commercially used rams come from Signet recorded flocks."
It is hoped more producers will use index selection to improve farm profits when indexes are adjusted, if needed, to reflect future sheep meat market trends.
For the past two years, SAC PhD student Huw Jones has surveyed abattoirs and retailers to determine likely future requirements for lamb. But reading trends has been harder than expected.
"There seems to be a lack of clear communication between retailers, abattoirs and producers about product requirements. True market requirements are not fully reflected in the penalties or premiums paid by abattoirs, particularly for over-fat lambs where penalties should be higher," he says.
It would appear that there will be continued demand for 18kg lambs to supply bone-in cuts and joints, but a new market for heavier lambs over 21kg may develop to produce bone-out meat, if large lean lambs can be produced, says Mr Jones.
The next step will be to present different selection index options for terminal sire breeds to the industry. "Hopefully, this will stimulate debate between the different sectors, which is vital to produce an index which will be well tailored to future markets and be acceptable to more producers," says Mr Jones.
He believes two indexes may be required to effectively cover both markets. The use of CT scanning technology to measure muscularity, which affects carcass conformation, may also be added to updated indices, adds Mr Jones. *
• Look at market demands.
• Offer different options.
• Include new traits?