Genetic parameters for bodyweight, wool, and disease resistance and reproduction traits in Merino sheep. 3. Genetic relationships between ultrasound scan traits and other traits
A. E. Huisman A B and D. J. Brown A CA Animal Genetics and Breeding Unit*, University of New England, Armidale, NSW 2351, Australia.
B Present address: Hypor, 5830 AA Boxmeer, The Netherlands.
C Corresponding author. Email: dbrown2@une.edu.au
Animal Production Science 49(4) 283-288 https://doi.org/10.1071/EA08172
Submitted: 28 May 2008 Accepted: 11 February 2009 Published: 6 April 2009
Abstract
The Australian Merino is the predominant genetic resource for both the lamb and sheep meat industries of Australia. There are very few studies that provide information on the relationships between wool and non-wool traits. This paper describes the genetic relationships between ultrasound scan traits and wool, disease resistance and reproduction traits in Merino sheep. Fleece weight and fibre diameter coefficient of variation were negatively correlated with ultrasound scanned fat and eye muscle depth (–0.10). Staple length, fibre curvature, and scrotal circumference were not correlated with scanned fat or eye muscle depth. Staple strength, number of lambs born and number of lambs weaned had a positive genetic correlation with fat and eye muscle depth (0.20–0.30). Faecal egg count had a negative genetic correlation with scanned fat (–0.10) and scanned eye muscle depth (–0.20). Results indicate that the combined improvement of carcass and wool characteristics in Merino sheep is possible.
Additional keywords: internal parasite resistance.
Acknowledgements
This research was funded by Meat and Livestock Australia, UNE and the NSW Department of Primary Industries. The authors would like to thank the Merino breeders and scanners who collected the pedigree and performance data used in this study. The work of Stephen Field, the Merino Genetic Services database manager, and that of Bronwyn Clarke, who manages the Merino Validation Project, is gratefully acknowledged.
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* Animal Genetics and Breeding Unit is a joint venture of the New South Wales Department of Primary Industries and the University of New England.
