Effect of selection for fleece weight on liveweight,
reproductive performance and wool characteristics in mixed age Romney
ewes
T. Wuliji, K.G. Dodds, R.N. Andrews, P.R. Turner and R. Wheeler
AgResearch, Invermay Agricultural Centre, Private Bag 50034,
Mosgiel, New Zealand.
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Proceedings of the New Zealand Society of Animal Production. 1999, 59: 27-29
This paper presents the analysis of 3525 annual production
records of mixed age Romney ewes in a fleece weight selected (HF) or
control (RC) flock over 11 years. HF ewes were significantly
(P<0.001) heavier than RC ewes for autumn live weight (8%), winter
live weight (9%), spring live weight (7%), greasy fleece weight (20%)
and clean fleece weight (19%). Small but significant (P<0.01) flock
differences were found for fibre diameter and yellowness. HF fleeces
were coarser and more yellow than RC fleeces. HF ewes were significantly
(P<0.01) higher than RC for ovulation rate (1.80 vs 1.73 SED 0.03),
number of lambs born/ewes lambed (1.63 vs 1.56 SED 0.02), and number of
multiple births/ewes lambed (60% vs 54% SED 2%), but lower (P<0.01)
for number of lambs weaned/lambs born (0.84 vs 0.88 SED 0.01). The
results indicate that single trait selection for fleece weight enhances
greasy and clean fleece weights, live weight and ovulation rate, with an
associated increase in FD and yellowness of their fleeces.
Keywords: NZSAPAB;
Romney; fleece weight; selection; ovulation rate; fibre
diameter.
Last Updated 06-08-1999
