Please use this identifier to cite or link to this item:
Title: Within- and across-flock genetic relationships for breech flystrike resistance indicator traits
Contributor(s): Brown, Daniel  (author); Swan, Andrew  (author); Gill, JS (author)
Publication Date: 2010
DOI: 10.1071/AN10102
Handle Link:
Abstract: Flystrike is a major cost for the Australian sheep industry. The industry is currently implementing selection strategies for flystrike resistance to reduce the need for breech flystrike prevention. The following indicator traits are used to select for breech flystrike resistance: wool cover, skin wrinkle on the body and breech, scouring (dags) and wool colour. The aims of this study were to estimate genetic correlations between these indicator traits and production traits using the Sheep Genetics database, to distinguish between within- and across-flock genetic relationships, and to quantify responses to selection using indexes that include breech wrinkle as a proxy trait for flystrike resistance. Breech flystrike indicator traits are all heritable; however, there are significant antagonisms between wrinkle score and some production traits, primarily fleece weight and fibre diameter. Thus, simultaneous improvement in both flystrike resistance and production will be most efficient when index selection is used. Our results show that, depending on the level of emphasis placed on breech wrinkle in the index, reductions in breech wrinkle score of 0.4-0.9 units can be achieved over a 10-year period. As across-flock relationships are generally stronger than within-flock relationships, breeders will be able to take advantage of this additional variation, depending on the relative merit of their flocks. Therefore, ram breeders should combine within-flock selection with across-flock selection where possible. Sheep Genetics released early breech wrinkle Australian Sheep Breeding Values in September 2009 to assist Merino breeders in making faster progress towards reducing breech wrinkle by using flock selection.
Publication Type: Journal Article
Source of Publication: Animal Production Science, 50(12), p. 1060-1068
Publisher: CSIRO Publishing
Place of Publication: Australia
ISSN: 1836-0939
Field of Research (FOR): 070201 Animal Breeding
Socio-Economic Outcome Codes: 830311 Sheep - Wool
Peer Reviewed: Yes
HERDC Category Description: C1 Refereed Article in a Scholarly Journal
Statistics to Oct 2018: Visitors: 125
Views: 128
Downloads: 0
Appears in Collections:Animal Genetics and Breeding Unit (AGBU)
Journal Article

Files in This Item:
3 files
File Description SizeFormat 
Show full item record


checked on Nov 30, 2018

Page view(s)

checked on Feb 8, 2019
Google Media

Google ScholarTM



Items in Research UNE are protected by copyright, with all rights reserved, unless otherwise indicated.