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Research has shown a technical description of a blend for most woollen carpet applications can be met with objective measurements, namely mean fibre diameter, fibre length after carding, wool bulk, proportion of medullation, base colour and vegetable matter content. The compressional property of wool as reflected in bulk is strongly related to mean fibre diameter and mean fibre curvature. Both these measurements can now be measured simultaneously with recently developed electronic instrumentation. While the processing implications of changes in mean fibre diameter are well understood, the processing implications of changes in objectively measured mean fibre curvature have not been investigated in detail. A total of 360 New Zealand Romcross type fleeces shorn from yearling sheep, with an individual range in mean fibre diameter of 23.2–40.6 μm and an individual range in mean fibre curvature of 34–115°/mm were used. The individual fleeces were sorted to create five, similar-sized, wool-processing lines with ...

This paper reviews the biology of wool, mohair and cashmere growth and the options available to sheep and goat farmers to manipulate the quantity and characteristics of fibre produced to meet processors' requirements. The annual pattern of fibre growth in sheep and fibre producing goats is photodependent and regulated by hormone action. In sheep and Angora goats, fibre growth rate is greater in summer than winter with the amplitude varying between breeds. Cashmere-producing goats grow fibre between the longest and shortest day after which it is shed. The large diversity in fleece and fibre characteristics between genotypes of sheep and goats can be used to change characteristics by selection. Fibre characteristics of greatest importance to processors are all of medium to high heritability. Negative genetic correlations between some important characteristics limit overall genetic progress achievable through selection. The principal non-genetic factors affecting fleece and fibre characteristics in both sheep and goats are age, nutrition, physiological status, disease and shearing regime. Further work is required to gain a greater understanding of biological changes occurring within the follicle and fibre during growth to facilitate the production of fibre of specific characteristics through breeding or altering animal management.