Ongoing research, involving Teagasc, UCD and the Agri-Food & Biosciences Institute (AFBI) in Northern Ireland, is shedding light on how best to finish purchased male lambs.

“The background to the work is the ongoing demand from processers to identify how farmers can reduce the taint problem associated with ram lambs that are slaughtered during the final quarter of the calendar year,” said PhD. student Noel Claffey, who is based at Teagasc Athenry.

“The first phase of the project got underway last September with the purchase of 200 male store lambs.

“Half of these were Scottish  Blackface; the others were Texel: Blackface crosses. Within each group, half had been castrated using a ring at 10 days of age. All the lambs were purchased off-farm.”

The Programme

Claffey said that groups of lambs were placed on a 36 day, all-concentrate feeding programme, which was preceded by a 12-day transition period.

“Under the timetable put in place, the groups were slaughtered at the end of October, November, January and April. Each of the groups comprised equal numbers of rams and wethers.”

“The transition period was marked by the gradual change from an all-forage to an all meal diet for the animals concerned. Up to their inclusion in the actual trial, the bought-in lambs were maintained at grass.”

The trial work at Athenry is being undertaken by a team, headed up by Professor Michael Diskin.

Results

The production-related results from the research confirm that Scottish Blackface ram lambs can achieve average daily growth rates of 255g/day with castrates averaging 218g. The equivalent figures for the Texel crosses were 364g and 315g respectively.

“Texel cross daily intakes averaged 1.65kgs/day with the Blackfaces averaging 1.4kgs. There were no gender differences, where intakes were concerned,” said Claffey.

The trials also confirmed that finished Blackface lambs had a higher fat cover, across the board, compared with the Texels. Conformation scores were consistently higher with the continental crosses.

Results from other aspects of the research will be available in the autumn.

Further research

A further trial, looking specifically at the sensory quality of lamb produced from entire males and wethers will get underway at Athenry in a few weeks’ time.

“A research team at AFBI has been assessing potential forage-based finishing options for bought-in store lambs. This work will also involve an investigation of the taste differences between the meat produced by young rams and wethers,” Claffey said.