PIGMENTATION TYPES - UNDERSTANDING THE HERITABILITY AND IMPORTANCE

The marketing and processing industry places reliance on wool producer s implementing appropriate management and breeding programmes to minim ise the risk of dark fibres and other contaminants in wool. Pigmented wool fibres can be an important source of dark fibres. In this paper, wool producers are made aware of the various sources of pigmented fibr es and recommendations for control through culling and breeding practi ses. Unlike visible (macroscopic) wool pigmentation, the presence of i solated pigmented fibres in otherwise white wool is unlikely to be see n and has only been recently recognised as a potential fault of Merino wool. Research has shown that isolated pigmented wool fibres in Merin os are largely a problem in young sheep (lambs and hoggets) and can be minimised through selection against associated non-wool fibre pigment ation visible on lambs and hoggets. Also discussed, are age-related ch anges in non-wool pigmentation traits and the possible relationships b etween these traits and hogget production traits (clean fleece weight, average fibre diameter and off-shears body weight).