Please use this identifier to cite or link to this item: https://hdl.handle.net/1959.11/14322
Title: Age at First Oestrus. A Useful Trait for Early Reproductive Performance?
Contributor(s): Newton, Joanna E  (author)orcid ; Brown, Daniel  (author); Dominik, Sonja  (author)orcid ; Van Der Werf, Julius H  (author)orcid 
Publication Date: 2013
Handle Link: https://hdl.handle.net/1959.11/14322
Abstract: An increasing number of Australian sheep breeders are joining ewes at 6-8 months of age, which is 6-12 months earlier than ewes are traditionally first joined. When joining at a young age, additional factors such as the attainment of sexual maturity must be considered. The age of sexual maturity is a challenging trait to measure with limited data currently available in sheep. This study explored several methods of analyzing age of first oestrus (AFO) data, an indicator trait for sexual maturity, and explored the relationship between AFO and early reproductive performance. Lambing records from 2218 Maternal-cross ewes joined naturally at 7-10 months were used, a subset of 906 ewes had AFO information collected through the use of teaser wethers. Heritability estimates for AFO were low (0.03 - 0.09) whilst estimates for number of lambs born and weaned at yearling age were 0.20 and 0.16 respectively. Genetic correlation between AFO and number of lambs born and weaned at yearling age were 0.45 and 0.51, respectively, but had high standard errors. Improving reproductive performance through the use of teasers to record AFO is not recommended, thus a need exists to find reliable measures for early reproductive traits including sexual maturity.
Publication Type: Conference Publication
Conference Details: AAABG 2013: 20th Conference of the Association for the Advancement of Animal Breeding and Genetics: Translating Science into Action, Napier, New Zealand, 20th - 23rd October, 2013
Source of Publication: Proceedings of the Association for the Advancement of Animal Breeding and Genetics, v.20, p. 86-89
Publisher: Association for the Advancement of Animal Breeding and Genetics (AAABG)
Place of Publication: Armidale, Australia
ISSN: 1328-3227
Fields of Research (FoR) 2008: 070201 Animal Breeding
060412 Quantitative Genetics (incl Disease and Trait Mapping Genetics)
Fields of Research (FoR) 2020: 300305 Animal reproduction and breeding
310506 Gene mapping
Socio-Economic Objective (SEO) 2008: 830311 Sheep - Wool
830310 Sheep - Meat
Socio-Economic Objective (SEO) 2020: 100413 Sheep for wool
100412 Sheep for meat
Peer Reviewed: Yes
HERDC Category Description: E1 Refereed Scholarly Conference Publication
Publisher/associated links: http://www.aaabg.org/aaabghome/proceedings20.php
Appears in Collections:Animal Genetics and Breeding Unit (AGBU)
Conference Publication

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

Page view(s)

2,166
checked on Jul 23, 2023

Download(s)

2
checked on Jul 23, 2023
Google Media

Google ScholarTM

Check


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