Abstract

The length of fibres after carding is strongly influenced by the minimum fibre diameter (MinFD) in winter in Low Staple Tenacity (LST) and High Staple Tenacity (HST) Romney sheep. In this study a further weakness was induced by a temporary reduction in fibre diameter at a point away from the winter minimum, and the influence on fibre length after carding (barbe) was determined. Forty adult rams of four genotypes (LST, HST, Drysdale and Merino) were offered a restricted diet for 14 days in early February. Fibre diameter was reduced over the treatment period in LST (by 26%), HST (19%), Drysdale (5.5%) and Merino (0.5%). Barbe was only significantly associated with MinFD during treatment in LST (r²=0.62, P<0.01) and not at all with change in fibre diameter. For each 1 um reduction in MinFD during treatment, barbe was reduced by 1-3mm.

MC, Smith, and AR Bray

Proceedings of the New Zealand Society of Animal Production, Volume 57, , 81-82, 1997