Crossbred ewes put to test
Crossbred ewes put to test
By Marianne Curtis
STUDIES of four crossbred ewes in lowland systems show Suffolk x Cheviots are the hungriest, Blue-faced Leicester x Blackfaces (Mule) are most prolific and Texel x Cheviots produce lambs with the heaviest carcasses at fat class three.
Conducted by the Agricultural Research Institute of Northern Ireland (ARINI), Hillsborough, trials were carried out on five lowland sheep farms in the province. Each farm received 20 ewes, a mix of Mule, Texel x Scottish Blackface, Suffolk x Wicklow Cheviot and Texel x Cheviot.
The first part of the trial looked at concentrate intakes of the different breeds in the six weeks before lambing, says researcher Lynne Dawson. "Suffolk x Cheviot ewes ate up to 17% more than the other three crossbreds. We are not sure why; their higher liveweight than the other breeds does not account for all of it."
At lambing, prolificacy and lambing ease were compared between the four crossbreds. "Mule ewes were the most prolific producing 24% more lambs a ewe as ewe lambs and 18% more as two or three year old ewes," says Dr Dawson (see table).
Although lambs from Mules had poorer conformation, with only 10% achieving E and U grades, compared with 31% of lambs from Texel x Blackface ewes, 26% from Suffolk x Cheviots and 28% from Texel x Cheviots, total lamb output for Mules was greatest.
"Over the three years of the study, Mule ewes produced 4.7 lambs a ewe mated, compared with 3.9 lambs a ewe mated for other crosses. So despite lambs from Mules having poorer conformation, their lamb output was £30 more than for other crosses," says Dr Dawson.
But replacement costs must also be considered when comparing ewe performance, she warns. "After three years, 32% of Mule ewes had been replaced, through culling or death, compared with 26% of Texel x Blackfaces and Suffolk x Cheviots and 22% of Texel x Cheviots." As ewes were relatively young, culling was mainly due to udder problems rather than lack of teeth.
There were no differences between breeds in mothering ability and milk yield, but lambing ease was best for Suffolk x Cheviot ewes. "Of Suffolk x Cheviot ewes, 75% lambed without assistance compared with 64% for other crossbred types in the study."