Abstract

Three lines of Romney sheep were selectively bred over 10 years for high or low staple tenacity, or were bred at random. Each crop of ewe and ram hoggets was weighed at strategic intervals throughout the year and staple tenacity was measured on mid side wool harvested in spring. Relationships of staple tenacity with live weight and liveweight change were examined by single and multiple regression analysis of data from a total of 2696 hoggets. The biggest single influence on staple tenacity in the ram hoggets was selection line, which accounted for 23.3 % (P2, but only 50 % of those with gains less than 20 g/day achieved that milestone. For the ram hoggets, the corresponding values were 66 % and 38 %. These findings provide a basis for liveweight targets to achieve chosen levels of staple tenacity in Romney hoggets.

MC, Smith, AR Bray, and DB Baird

Proceedings of the New Zealand Society of Animal Production, Volume 60, Hamilton, 171-173, 2000