31 March 2000

Switch breed for output lift?

By Jessica Buss

IMPROVING financial returns in the hill sheep sector may require producers to rethink the breeds kept and to begin crossbreeding in their flocks.

Agricultural Research Institute of Northern Ireland researcher Alistair Carson told BSAS delegates that breed choice was important and there were options, of which all aspects must be considered. "But there is potential to improve output and carcass quality."

Dr Carson studied the use of Wicklow Cheviot ewes to replace Scottish Blackface ewes on six hill farms in Northern Ireland. A total of 1440 ewes were mated in each of two years.

Blackie ewes were tupped with Scottish Blackface, Bluefaced Leicester and Texel rams, and Cheviots mated with Cheviot, Suffolk and Texel rams.

Lambing percentages and lamb mortality were similar for both ewe breeds. But Cheviots achieved a 7% higher weight of lambs weaned a ewe, while the weight of lambs weaned/kg of ewe was similar. The Cheviot had the additional benefit of higher quality lamb carcasses, with superior conformation.

"Cheviot ewes are bigger, but on many units stocking rates are declining so they have feed available for bigger ewes.

"Individual producers choice will depend on the farm, but there is an opportunity to use Cheviots on some," said Dr Carson.

Cross breeding was also found beneficial to the output of both ewe breeds, he added. A Cheviot ewe crossed with a Texel or Suffolk produced 12% more lamb output than when pure bred.

When crossbred, Blackie ewes produced 20% more weight of lamb at weaning than when pure bred.

Texel cross lambs from both ewe breed proved to have better carcass conformation than other crossbreds in the study, he added.

"A Blackie lamb is not the only one that will survive in the hills; a crossbred lamb benefits from hybrid vigour," said Dr Carson.

But flockmasters should consider the effects of changing ewe breeds and crossbreeding on one of their main markets – that for lowland replacements, he added.

That subject was tackled by his colleague Lynne Dawson, who is completing another project comparing the performance of Scottish Blackface and Wicklow Cheviot cross females for lowland producers.

Mules were compared with Texel X Blackface, Texel x Cheviot and Suffolk x Cheviot crosses as ewe lambs and hoggets on four lowland farms in Northern Ireland.

When crossed with Suffolk or Texel rams, Mules were most prolific as ewe lambs and again as hoggets.

Mule ewe lambs produced 1.18 lambs each, but Suffolk x Cheviot ewe lambs suffered a high % of barren ewes and only produced 0.79 lambs a ewe tupped.

"As hoggets, Mules produced 1.8 lambs a ewe, compared with 1.3-1.4 for the other three breeds," said Dr Dawson.

But Mule lambs were expected to return poorer conformation grades than the other cross breeds. These other cross breeds may also last longer and could suit a low labour system, added Dr Carson.

"But we should question the stratified system of supplying lowland replacements from hill flocks. These sectors may not be so dependent on each other in future," added Dr Carson. &#42

Hill sheep producers should reconsider the breeds they use and try crossbreeding, says Alistair Carson.

INCREASING OUTPUT

&#8226 Change breed?

&#8226 Cross-breeding.

&#8226 Better lamb conformation.