Pigmented fibres in white-skirted fleece wool from Piebald Merino sheep

Abstract

White-skirted fleece wool from 68 piebald Merino sheep was divided into four portions that were sampled and measured for pigmented fibres. The piebald sheep were identified by the presence of pigmented fibre spots (usually one), varying in size from 2 mm diameter to over 50% of body surface area, and their location conformed to no particular pattern. The majority of samples for each portion (72-82%) had no detected pigmented fibres. There were 14.7% of piebald sheep with a concentration of isolated pigmented fibres (PFC) of at least 1 per 10 g scoured staples (taken to be the threshold of commercial importance) for their white fleece wool. While most PFC values were below the commercial threshold, there is a risk that some pigmented areas on piebald sheep may be missed during shearing. Of the various records taken for macroscopic pigmentation on the piebald sheep, only the scores for pigmented fibres at the horn sites (HSF) were significantly correlated (r=0.37; P<0.01) with PFC. The HSF scores were significantly correlated (P<0.05) with several other types of non-fleece pigmentation.