Effect of sire genotype on lamb growth and carcass productivity
G.B. Nicoll, J.W. Skerritt, J.L. Dobbie and T.J. Grimwood
Landcorp Farming Limited, PO Box 1235, Hamilton, New Zealand
Proceedings of the New Zealand Society of Animal Production. 1998,
58: 136-139
The growth and carcass traits of 774 lambs out of Romney ewes and sired
by Suffolk (S), Landcorp Lamb Supreme (LS), Texel (T) and Romney (R)
rams were compared when slaughtered on five occasions (groups 1 to 5):
November 1995, February, March, May and July 1996. Forty carcasses per
slaughter group were dissected into commercial cuts of saleable meat,
fat trim and bone. S- and LS-sired lambs had heavier pre-slaughter
liveweights than T-sired lambs (38.4 ± 0.27, 38.5 ± 0.26, vs 36.3 ± 0.27
kg respectively; P<0.001), which in turn were heavier than R-sired lambs
(35.0 ± 0.29 kg; P<0.001). S-sired lambs had heavier hot carcass weights
than both LS- and T-sired lambs in slaughter groups 4 and 5 (+0.9 to
+1.9 kg; P<0.01); R-sired lambs were significantly lightest in all
slaughter groups (-0.7 to -3.9 kg; P<0.05). S- and R-sired lambs had
greater adjusted GR tissue depths than LS-sired lambs in later slaughter
groups. T-sired lambs were generally intermediate between LS- and
R-sired lambs. R-sired lambs produced less weight of saleable meat than
S-, LS- and T-sired lambs (by 1.4 to 1.7 kg; P<0.01). Lambs sired by
Landcorp’s terminal sire breeds out-produced those sired by the
company’s maternal R sire breed. S-sired lambs exhibited rapid growth
early in the season, but increased fat levels later in the season
compared with LS-and T-sired lambs.
Keywords: NZSAPAB;
lamb; sire genotype; growth; carcass; saleable meat.
Last Updated 12-09-1998
