Sheep producers wishing to increase carcass performance by more than 2kg a lamb, and carcass value by more than £3 a lamb, should consider using high-index rams, according to results from the first year of the integrated supply chain for the future lamb market.

With a full set of data now available from nine commercial flocks trialled in 2005, all but one had shown positive improvements in terms of carcass and liveweight performance, independent sheep consultant Lesley Stubbings told visitors to a briefing at this week’s Royal Show.

“Having never used high-index rams before, one producer in Cheshire increased carcass weights by 0.87kg a lamb and carcass value by £2.40.

Others were showing gains of 2.17kg a lamb and values of £3.06 a lamb,” she explained.

Figures for 2006-born lambs were equally promising.

“One farm has seen improvements of 1.42kg a lamb and up to £4.20 on carcass value,” she added.

However, Ms Stubbings highlighted that, with the use of high-index rams, many lambs were finished heavier than the 21kg processor requirement.

“Where this is occurring, producers will have to look at individual estimated breeding values for specific traits to improve performance without incurring financial penalties for overweight lambs.”

Some would also have to consider finishing earlier to maximise performance, while remaining in specification, added managing director of Welsh Country Foods, Trevor Hanger.

But, he told producers the payment mechanism was likely to change in future to suit these heavier lambs.

“Whether that’s up to 23kg or even as far as 30kg, there is a clear intention to cut more joints from lambs and produce and market them according to season and time of year to suit the customer.”

fwlivestock@rbi.co.uk