Differences in wool characteristics in lines of sheep with high
or low levels of backfat thickness.
N.C. Merrick, D.B. Baird, J.C. McEwan, R.W. Purchas
AgResearch Lincoln, P.O. Box 60, Lincoln, New Zealand
Proceedings of the New Zealand Society of Animal Production.
2000 60: 159-161
Relationships between backfat thickness and wool characteristics
for lines of Coopworth and Southdown sheep, selected for or against
backfat thickness, were studied between years and between different age
classes. On average, the lean Coopworth line grew 230 g more greasy wool
(P<0.001), which was 1.7 mm finer (P<0.001) and less variable in
diameter (P<0.05) than the fat line. Other measured wool
characteristics were not affected. The Southdown lines did not differ in
fibre diameter, variability of diameter or curvature, within age groups.
Southdown lambswool was finer (P<0.001) and less variable in diameter
(P<0.001) than hogget or ewe wool (23.6 ± 4.9, 27.0 ± 5.6
and 26.7 ± 5.4). Fibre diameter differences observed in the
Coopworth lines may have been a founder effect, as subsequent selection
had little impact on it. Selection for leanness increased greasy fleece
weight without affecting fibre diameter or staple length.
Keywords: NZSAPAB;
wool; fibre diameter; leanness; Coopworth; Southdown.
Last Updated 12-07-2000
