The relationship between fleece weight and efficiency in Romney and Corriedale sheep

Abstract

In two experiments with Romney ewes and one with Corriedale ewes the efficiency with which individual sheep converted feed to wool was estimated by feeding the ewes in pens and relating wool grown to feed intake. In the Romney experiments the ewes employed were selected on the basis of either high or low fleece weight whilst under grazing conditions. Considerable differences in efficiency between sheep were observed. The efficiency of individual ewes was then correlated with their grazing fleece weights. Estimates of this correlation coefficient varied from 0.7 to 0.9. The significance of this high correlation is discussed.