Setting the records straight
IDENTIFYING STRAINS of sheep which perform well on a certain farm or under specific management can, many would argue, be done by eye. But that fails to get to the bottom of the situation, according to one Perthshire breeder.
Aberfeldy-based Ian Duncan-Millar says true judgements require accurate records and detailed assessments of ewe and lamb performance – something you can’t tell just by looking at the sheep.
“The records you need to make these decisions correctly only come from performance recording. This gives you information such as growth rate, muscle depth and litter size.”
Mr Duncan-Millar began performance recording his Blackface flock at Wester Tullich in 1996. Then he picked out 200 of the best looking ewes from the flock of 650 to form a nucleus flock to record using Signet’s Sheepbreeder Hill Index.
“These ewes are managed the same way as the main flock. The only difference is when they are split off for tupping and lambing.”
Tups used on nucleus ewes are selected from the flock’s 10 lambs with the highest indexes, with tups from the Blackface Sire Reference Scheme (BSRS) used on some ewes. “With the home-bred tups, we don’t pick lambs just on index or on looks, it’s a matter of balancing the two.”
And it’s a policy which has worked for Mr Duncan-Millar, as indexes have increased rapidly since recording started. “In 1996 our average ram lamb index was 37, last year it was 201.
“Much of this improvement has come in the last four years since we joined the BSRS. Before that it was creeping up gradually, but access to top genetics available from BSRS flocks has meant more rapid improvement.”
Progress among ewes has been slower, he admits. But this is due to the nature of selection. “We’re only looking for a handful of tup lambs every year. With the females we need far more, so have to accept the indexes of replacement ewes will vary more than tups.
“The nucleus flock is also in the National Scrapie Plan, so we lost some ewes which had non-resistant genotypes and these were replaced with ewes from the main flock.”
While the emphasis is on the nucleus flock, Mr Duncan Millar is keen to see improvements in the main flock, so high index tup lambs not required for nucleus breeding are used in the main flock. “This is helping to improve performance and lift the overall profitability of the farm.”
It is, after all, profit which has to be the main driver, he explains. “It has meant taking a different view of our sheep, but when you see the improvement made by flocks which have been recording for longer than we have it focuses the mind.”
One flock which has been recording since 1992 has seen huge improvements in slaughter lambs sold over the last 10 years, says Mr Duncan-Millar. “In 1992 its average lamb weight was 15.4kg deadweight, with 49% grading as Os and a further 49% as Rs.
“In 2002 just 12% were Os, while 65% were Rs and a further 22% were Us. On top of this carcass weight has improved to 18.2kg, an improvement of nearly 3kg.
“This improvement has meant improved returns and more lambs suitable for the mainstream supermarket trade.” And the great thing is that improvements are cumulative and permanent, says Mr Duncan Millar. “So we’re always improving on what we’ve done before and if we stopped tomorrow we would be ahead of where we started.” Looking to the future, he believes more hill flocks will come around to performance recording.
“The progress made since beginning recording means we”re all selling more finished lambs which meet buyer specification. This is exactly what we need to do in the new de-coupled era.”
The only regret is not starting sooner, he adds. “But we”re still ahead of many Blackface flocks, so there may be opportunities to sell high index breeding stock to them yet.”
PANEL HILL-2 INDEX EXPLAINED
Performance in hill breeds is measured by recording a number of traits, including the number of lambs reared, eight week and weaning weight, explains Sigent breeding services manager Sam Boon. “Lambs are also ultrasound scanned at weaning to assess fat and muscle depth. EBVs are then produced, with each trait given a weighting according to its significance to hill flocks.” The aim of the index is to improve the financial productivity of the hill ewe without compromising her ability to survive in the harsh hill environment, he adds.
BOX BLACKFACE RECORDING
Uses Hill-2 index
Improved lamb weights
Increased lambs in spec
Improvements cumulative and permanent