Relationship between wax, suint and fleece rot: effect of sample preparation, time of sampling and fleece rot induction

Abstract

The major factors thought to affect the relationship between wax and suint and fleece rot susceptibility were examined. Time of sampling and fleece rot induction were the major factors which resulted in changes in wax and suint levels in the fleece and their relationship with fleece rot. Variation in staple portion used for extraction did alter the yields of wax and suint, but these yields were highly correlated to full staple values in the case of wax (r = 0.77-0.92) and lower in the case of suint (r = 0.23-0.77). Variation in length of staple used did not alter the relationship between wax and suint levels and fleece rot. We conclude that wax would be a more suitable indicator of fleece rot susceptibility than would suint because of its more stable relationship with fleece rot. Differences between sheep affected and unaffected with fleece rot in wax and suint values were small and consistent for the 15 Merino genotypes sampled. The evaluation of wax for indirect selection against fleece rot will depend on further evaluation of the required genetic parameters and a more cost-effective means of measurement.