Lambs reach slaughter weight earlier on multi-species swards – UCD research

Lambs grow quicker and reach slaughter weight earlier when they graze multi-species swards, according to UCD PhD student, Connie Grace.

Grace presented the research findings from her first year’s trial work at the recent ASA Sheep Technology Training day held in UCD’s Lyons Estate.

Early results show that lambs thrive better when they graze multi-species swards compared to grass and grass-clover swards, she said.

The research, which is funded by the Department of Agriculture, as part of the Smart Grass Project examined the difference in ewe and lamb performance from grass only, grass-clover and multi-species swards.

Grace said that lambs which grazed the six-species sward (see below) had the highest weaning weights, and these lambs were 4kg heavier at this time compared to those on perennial ryegrass swards.

Lambs on the six-species sward also had the highest growth rate from birth-to-weaning, she said, with a growth rate of 303g/day, while the perennial ryegrass lambs had a growth rate of 285g/day.

“The same pattern was also seen when the lifetime growth rates of the lambs were looked at, as the lambs that grazed the six-species sward grew faster that the perennial ryegrass lambs.

“This had an effect on the days-to-slaughter, the lambs that grazed the perennial ryegrass only swards were slaughtered 25 days later that the lambs that grazed the six-species mix,” she said.

Grace also said that lambs which grazed multi-species swards had a lower worm burden and needed less dosing throughout the year, compared to those on the grass and grass-clover swards.

However, she cautioned that the results presented were from the first year of her trial work, and the trial will continue for another year to further clarify these results.

Grass only mix
  • Grass: perennial ryegrass
  • Nitrogen input: 163kg/ha
  • Concentrate input: 8kg/ewe

Grass-clover mix
  • Grass: perennial ryegrass
  • Clover: white clover
  • Nitrogen Input: 90kg/ha
  • Concentrate Input: 19kg/ewe

Six-species mix
  • Grass: perennial ryegrass and timothy.
  • Legumes: white clover and red clover.
  • Herbs: plantain and chicory.
  • Nitrogen input: 90kg/ha.
  • Concentrate input: 7kg/ewe.

Nine-species mix
  • Grass: perennial ryegrass, timothy and cocksfoot.
  • Legumes: white clover, red clover and trefoil.
  • Herbs: plantain, chicory and yarrow.
  • Nitrogen input: 90kg/ha.
  • Concentrate input: 18kg/ewe.