Genetic alternatives to mulesing and tail docking in sheep: a review
P. J. JamesQueensland Department of Primary Industries and Fisheries, Animal Research Institute, 665 Fairfield Road, Yeerongpilly, Qld 4105, Australia. Email: peter.james@dpi.qld.gov.au
Australian Journal of Experimental Agriculture 46(1) 1-18 https://doi.org/10.1071/EA05100
Submitted: 23 March 2005 Accepted: 14 September 2005 Published: 9 February 2006
Abstract
A genetic solution to breech strike control is attractive, as it is potentially permanent, cumulative, would not involve increased use of chemicals and may ultimately reduce labour inputs. There appears to be significant opportunity to reduce the susceptibility of Merinos to breech strike by genetic means although it is unlikely that in the short term breeding alone will be able to confer the degree of protection provided by mulesing and tail docking. Breeding programmes that aim to replace surgical techniques of flystrike prevention could potentially: reduce breech wrinkle; increase the area of bare skin in the perineal area; reduce tail length and wool cover on and near the tail; increase shedding of breech wool; reduce susceptibility to internal parasites and diarrhoea; and increase immunological resistance to flystrike. The likely effectiveness of these approaches is reviewed and assessed here. Any breeding programme that seeks to replace surgical mulesing and tail docking will need to make sheep sufficiently resistant that the increased requirement for other strike management procedures remains within practically acceptable bounds and that levels of strike can be contained to ethically acceptable levels.
Additional keywords: flystrike, Lucilia cuprina, tail length.
Acknowledgment
Funding for this project was provided by Australian woolgrowers and the Australian Government through Australian Wool Innovation Limited.
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