The prevalence of fleece derangement in some Australian and New Zealand flocks infested with the sheep itch mite, Psorergates ovis

Abstract

Extract

A characteristic fleece derangement of Merino sheep was reported in South Africa Bekker, (1928) and recognized in Australia (A. L. Rose, 1932, priv. comm.) before discovery of the causal agentPsorergates ovis by Carter in 1941. Infested sheep may show one or more of the following changes:

	The tip of the staple has a spiral point and the protruding wool tufts are bleached as if chewed.
	The fleece may be matted, perhaps with dried saliva, in addition to tangling of the fibres.
	Scurf may be present on the skin.
	Yellowish discoloration of scurf and wool may be present.
	The skin may be thickened, with cordlike wrinkles.
	There may be lead-coloured patches on the skin.