Maximum Eye Muscle

Summary

There were no significant differences between groups in lamb live weights or lamb growth rates at either site. This is consistent with the lack of difference in the sire EBVs for PWT between the groups. Lambs in the high muscle group at Broomehill had 1.56 millimetre deeper eye muscle than lambs in the low group when scanned live at an average weight of 40.85 kg. This was even greater than the difference predicted by Lambplan. In the second consignment of lambs from Shackleton, the lambs in the high group were on average 1.5 millimetres fatter at the GR site than lambs in the low group, which is also higher than Lambplan predictions.

No significant differences between groups were seen in the retail meat yield of the easy carve leg, eye of short loin and french rack cuts when they were measured at one slaughter from each site. Lambs from the high muscle group tended to have slightly heavier loin and rack cuts than lambs from the low muscle group, while sire selection based on EMD tended to have a smaller influence on the retail weight of the leg cut. A significantly deeper eye muscle in lambs scanned live, did not appear to translate to a significantly higher retail meat yield, even in the loin and rack cuts which are comprised of eye muscle.