Genetic changes generated within the Katanning Merino Resource flocks
J. C. Greeff A B and G. Cox AA Department of Agriculture and Food Western Australia, 10 Dore Street, Katanning, WA 6317, Australia.
B Corresponding author. Email: jgreeff@agric.wa.gov.au
Australian Journal of Experimental Agriculture 46(7) 803-808 https://doi.org/10.1071/EA06007
Submitted: 9 January 2006 Accepted: 21 May 2006 Published: 8 June 2006
Abstract
Genetic changes for clean fleece weight, fibre diameter and hogget body weight were determined in the Katanning Merino Resource flocks from 1982 to 2004. From 1982 to 1992 genetic trends are presented for individual studs that used mainly subjective classing selection methods (Phase 1) and the genetic trends from 1997 to 2004 demonstrate the genetic changes that can be achieved from using estimated breeding values calculated from best linear unbiased prediction (BLUP) mixed methodology (Phase 2). The results during the first phase show that very few genetic changes occurred in most studs, except for the 4 studs of the Performance Sheep Breeding strain which showed genetic increases in hogget body weight. The genetic trends show that some studs generated change towards their breeding objective, while others show no changes or changes in the opposite direction. In contrast, the use of BLUP estimated breeding values resulted in positive changes in clean fleece weight, fibre diameter and body weight in accordance with the defined breeding objectives.
Acknowledgements
The authors wish to acknowledge Dr Roger Lewer for establishing these flocks and would also like to thank all the Merino ram breeders who have participated in this project since 1982. Many technical staff were involved in these flocks and we would like to thank them for their support over all these years. This project was funded by the Department of Agriculture Western Australia.
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