7 July 1995

Quality rams bring

early lamb success

Marketing lambs earlier in the season has increased returns by up to £5/head at Plumpton College, East Sussex. Terminal sires with high indexes for muscle depth, leanness and growth rate are the secret ingredient. Rebecca Austin reports

RAMS with high indexes for muscle depth, leanness and growth rate have increased the value of the lamb crop at Plumpton College, Lewes, East Sussex, by between £2.50 and £5 a head.

Lambs finish more quickly and have improved conformation, according to farms director Des Lambert. As a result they classify better than those sold prior to the change in policy.

"Improved growth rates enable us to sell lambs a few weeks earlier, so we cash in before the market is flooded and collapses," says Mr Lambert.

"We profit from extra kg/head in terms of conformation and growth rate, as well as p/kg. In all I reckon we receive an extra £2.50 to £5 a lamb."

Since the college started to buy rams with indexes of about 160 points from local Texel breeder Alan Draper the percentage of lambs screening E, U, R and 2 or 3L has improved to 83% for this years lambing, compared with 65% at the beginning of the decade.

Indexes are calculated by Meat and Livestock Commission fieldsman from eight-week and 21-week weights. Back fat and eye muscle depth are also included. Rams sold by Mr Draper to Plumpton College for about £350 recorded 34mm muscle depth and under 2.2mm back fat when scanned as ram lambs at his Highfields Farm.

Mr Draper has seen eight-week weights increase from 18.1kg for all Texel lambs in 1991 to average 26.8kg this year. "Lambs born from high index ewes, sired by high index rams, are now showing a growth rate of 0.41kg/day," he explains.

Although it is difficult to quantify financial gain – due to market fluctuations – since the college started using high index rams, a graph plotted by Mr Lambert shows its lamb price to be consistently higher than the national average over five years.

Weaned and fed creep

Half the 500-strong flock lambs in January. Lambs weighing over 18kg liveweight at six weeks are weaned and fed creep indoors. Once they reach 30kg liveweight, they will have eaten between 0.75kg and 1kg/day of 18% protein lamb creep with added Deccox – providing 0.6kg average daily liveweight gain.

Nearly three quarters of the lambs fit into this bracket and most are sold when 12 weeks old. This spring they averaged £52 a lamb.

They are marketed by Martin Crowhurst, livestock marketing manager for Ashford-based Hobbs Parker, who places them with various abattoirs, depending on trade.

The rest of the January-born lambs are finished within 16 to 20 weeks outdoors, with creep available. These achieved an average £45.50 a head this year. The second flock lambs in March, with the first draw of lambs at the beginning of June, and the bulk selling by mid-July.

"Indexes act as an extra tool for producers to compare ram performance within flocks and give the commercial buyer more of a chance to pick the best ram," explains Mr Lambert. "But farmers shouldnt forget visual assessment, even though it seems rams with the best conformation tend to have the highest indexes."

Mr Crowhurst would like to see some figures which compare rams across flocks as, he says, what may be a high indexed ram within one flock may not score so well in a flock with higher overall performance.

"Also, one of the biggest problems post weaning is waiting for lambs to come forward again. Some lambs dont flesh up again for 12 weeks and maybe there are some rams which perform better over this period than others," he says.

&#8226 Farm size: 607ha (1500 acres); 162ha (400 acres) rented from National Trust.

&#8226 Cropping: 455ha (1125 acres) grass, rest wheat, barley, oilseed rape and forage maize. Most of the sheep grazing, at 12 ewes a hectare, is downland scarp slopes and environmentally sensitive area grassland.

&#8226 Stocking: 210-head dairy herd, 100 sows, 25 barley beef cattle plus the 500-head ewe flock made up of Mules, Suffolk x Mules and a small pedigree Texel flock. From late July 1100 store lambs are bought in and sold from September onwards.

&#8226 Performance: Last years gross margin for the sheep unit was £62 a head for ewes and lambs, or £744/ha (£301/acre). Variable costs £18.30 a ewe, feed costs £5.90 a ewe, vet and med £3.60 a ewe. Output £80 a ewe for 687 lambs sold.

Julian Fuller with the ewes and lambs up on the downland. Texel rams fit the system because they do well in the extensive system. Their lambs remain lean at heavier weights, which makes more money in p/kg.

Julian Fuller (left), the college shepherd, and Martin Crowhurst, Hobbs Parker, with some of the March-born lambs ready for marketing.