15 November 1996


Increased membership of sire reference schemes reflects their continued success. Rebecca Austin outlines progress being made by each

ONGOING success of sire reference schemes is encouraging new breeders and groups to join up all the time, says Stewart Hall, Meat and Livestock Commission sheep strategy manager.

The schemes success can be measured in terms of genetic improvement as identified through best linear unbiased prediction (BLUP). It is also apparent in commercial producers through their enthusiasm for high index and SRS rams at this seasons sales. And nearly all pedigree breeders have seen higher demand for rams sold privately off the farm.

As a result, sire reference schemes have been established for the Beulah Speckled Face and Bluefaced Leicester breeds and one is planned by the CAMDA Welsh Mountain group breeding scheme. (For more details turn to pS31).

It is the MLCs role to promote the concept of SRS by providing technical advice and guidance alongside Signet, but, as Mr Hall says, each SRS group must set its own objectives. Outlines for these for current schemes are detailed opposite and on pS26.

"We are trying to encourage increased efficiency in terms of a higher quality carcass," explains Mr Hall. "Genetic improvement is one long-term strategy to continue to improve performance within the industry. We are now seeing a start, but it is only the tip of the iceberg. Half of todays lambs still do not meet todays mass market requirements and we are unlikely to shift that dramatically in the near future."

Costs of production, carcass weight and efficient production are other areas targeted for improvement. Although the MLC cannot afford to financially back everyone involved in the industry, the current research proposal is secured to the tune of £1m. This will go toward work on CT scanning, genetic linkages and the hill sheep project. A further £42,000 – half from MAFF – has been given to the Suffolk, Charollais and Texel SRSs for three years of promotional training and demonstrations.

Most breeds are aiming to increase growth rates and muscling, while keeping fat levels in check. It has been estimated that the ratio of the growth of lean meat to fat is 3:1. Heritability for 21-week weight is 35% to 40%, muscling 30% to 40% and lean 45%.

"One huge advantage to the SRSs is the sheer volume of animals involved. For example, the chances of breeding a near perfect animal are 1:1000. That means if you breed 100 lambs each year you will only produce that perfect lamb once every 10 years," explains Mr Hall. "But the Charollais and Centurion (Poll Dorset) schemes breed about 3000 lambs each season so they should each produce three top class lambs each year. It is one of the most obvious reasons for co-operative breeding. Remember we are dealing with biology, so if breeding decisions are based on large numbers we improve the chance of getting it right.

"I am convinced BLUP works. You can see it in both pedigree and commercial flocks. But you have to remember that these figures should only be used as another piece of information in a breeding decision. I would never recommend anybody to breed purely on figures without physically assessing the animal as well. SRS, in practice, therefore, cannot achieve full genetic potential due to other objectives. And it is important to balance genetic improvement with a huge number of breeders to give the genetic variation required."

More and more lambs are sired by high index tups. The benefits include improved carcass confirmation and growth rates – and premium prices.

Sire reference schemes 1996

SchemeNo membersNo ewesNo lambs




Scottish Blackface91,3301,920



North Country Cheviot55921,014


Centurion (Poll Dorset)102,1732,859

Berrichon du Cher36699