The effect of some fleece characters on the skin wax layer and fleece rot development in Merino sheep following wetting

Abstract

This paper describes changes occurring on the skin surface following wetting and during the development of fleece rot and examines the effect of some fleece characters on these changes. One day of wetting reduced the average thickness of the skin wax layer from 7.82 to 4.90 ¦m, but there was little change In the proportion of the skin surface covered by wax. When hyperaemia of the skin was first noted the proportion of the skin surface covered by wax had decreased from 97.8 to 47.5% and the average thickness of skin wax had decreased to 3.64 ¦m. Cholesterol content of the skin wax increased steadily from the first day of wetting as fleece rot developed, whereas lanosterol content increased only in the early stages of fleece rot. Suint content of the fleece, measured before wetting commenced, was positively correlated with fleece rot score at all times during wetting. Suint also showed significant correlations with moisture content of the proximal portion of the staple, percentage of the skin surface covered by wax and cholesterol and lanosterol content of the wax. No relationship was observed between fleece rot score and fleece wax content, wettability, staple formation, tip formation, crimp definition or initial thickness of the skin wax layer.