Fibre diameter profiles- potential applications for improving fine-wool quality

Abstract

Experiments were conducted to examine the potential value of measurement and monitoring of fibre diameter changes throughout the wool-growing year for improving wool quality and wool staple strength of fine Merino wool grown in temperate environments of NSW. This work included an on-farm survey of fibre diameter profile patterns, which indicated the relative magnitude of sources of variation in fibre diameter profiles. This provided the starting point for other, more detailed investigations focused on the effects of reproduction on fibre diameter profile, the potential for using grazing management to improve wool quality and utilization of fibre diameter profile data in Merino breeding for the improvement of fine-wool quality. Despite prolonged drought conditions, there was evidence of regional differences in environmental effects on fibre diameter profile characteristics. It seems that less than 400-500 kg green DM/ha is required to suppress fibre diameter in spring sufficiently to reduce mean fibre diameter. However, this pasture benchmark is at best regarded as preliminary as there appear to be several important interacting environmental factors. Phenotypic evidence supports the existing use of coefficient of variation of fibre diameter over either of the components of fibre diameter variation (along or between fibres) as a selection criterion in Merino breeding programs.