Abstract

This study tested and compared different implementation strategies for genomic selection for Norwegian White Sheep, aiming to increase genetic gain for maternal traits. These strategies were evaluated for their genetic gain ingrowth, carcass and maternal traits, total genetic gain, a weighted sum of the gain in each trait and rates of inbreeding through a full-scale stochastic simulation. Results showed genomic selection schemes to increase genetic gain for maternal traits but reduced genetic gain for other traits. This could also be obtained by selecting rams for artificial selection at a higher age. Implementation of genomic selection in the current breeding structure increased genetic gain for maternal traits up to 57%, outcompeted by reducing the generation interval for artificial insemination rams from current 3 to 2years. Then, total genetic gain for maternal traits increased by 65%-77% and total genetic gain by18%-20%, but at increased rates of inbreeding.

Highlights

  • Maternal traits are important for sheep produced in pasture-based production systems where overall production efficiency depend heavily on the maternal abilities of ewes (Conington, Bishop, Waterhouse, & Simm, 2004)

  • The genetic gain achieved with pedigree based BLUP (PED)-3 was very similar to what is estimated genetic gain for Norwegian White Sheep (NWS) under the current breeding programme

  • Relative to PED-3, all genomic selection schemes facilitated a large increase in genetic gain for maternal traits, but this was accompanied by a reduction in gains for the other two trait categories

Read more

Summary

Introduction

Maternal traits are important for sheep produced in pasture-based production systems where overall production efficiency depend heavily on the maternal abilities of ewes (Conington, Bishop, Waterhouse, & Simm, 2004). The Norwegian White Sheep (NWS) breeding programme has experienced a large genetic gain in litter size (Eikje, Ådnøy, & Klemetsdal, 2008), and this increases the demand for a ewe that can feed and raise multiple lambs. Implementation of genomic selection is expected to improve genetic gain for maternal traits already included in the breeding goal and facilitate effective selection for new maternal traits to be included in the future. Typical challenges when genomic selection is to be implemented in sheep are the large number of breeds. These tend to be numerically small, causing small reference populations and

Objectives
Results
Conclusion

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.