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REVIEW (Open Access)

Dermatophilosis (lumpy wool) in sheep: a review of pathogenesis, aetiology, resistance and vaccines

Ross L. Tellam A , Tony Vuocolo A , Stuart Denman A , Aaron Ingham A , Gene Wijffels A , Peter J. James https://orcid.org/0000-0003-1237-0212 B and Ian G. Colditz https://orcid.org/0000-0001-9497-5148 C *
+ Author Affiliations
- Author Affiliations

A Agriculture and Food, CSIRO, 306 Carmody Road, St Lucia, Qld 4067, Australia.

B Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, Brisbane, Qld 4072, Australia.

C Agriculture and Food, CSIRO, New England Highway, Armidale, NSW 2350, Australia.

* Correspondence to: Ian.Colditz@csiro.au

Handling Editor: Robin Jacob

Animal Production Science 62(2) 101-113 https://doi.org/10.1071/AN21119
Submitted: 2 March 2021  Accepted: 1 September 2021   Published: 16 November 2021

© 2022 The Author(s) (or their employer(s)). Published by CSIRO Publishing. This is an open access article distributed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License (CC BY-NC-ND)

Abstract

Lumpy wool (dermatophilosis) develops following prolonged wetting of sheep when bacterial proliferation in wool and on skin induce an exudative dermatitis, causing a superficial skin lesion and damage to wool follicles and fibres. The incidence of dermatophilosis is strongly dependent on wet and warm weather and, hence, infection is sporadic. While older animals are less at risk than are lambs, it is unclear whether this reflects naturally acquired immune resistance or the maturation of skin and wool fibres. Dermatophilosis directly causes wool production losses and it also is a risk factor for blowfly strike, which has a substantial economic impact and increasing challenges associated with current control procedures. This review assessed research on the bacterial causes of lumpy wool, the characteristics of the resulting immune defence reactions in sheep, current control strategies, and limitations of previous attempts to control lumpy wool by sheep vaccination.

Keywords: acquired immunity, antibiotics, dermatophilosis, dermatitis, Dermatophilus congolensis, genetic resistance, local immunity, lumpy wool, vaccines.


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