Please use this identifier to cite or link to this item: https://hdl.handle.net/1959.11/52046
Title: Optimal mating strategies to manage a heterozygous advantage major gene in sheep
Contributor(s): Raoul, J (author); Palhière, I (author); Astruc, J M (author); Swan, A  (author)orcid ; Elsen, J M (author)
Publication Date: 2018
Open Access: Yes
DOI: 10.1017/S1751731117001835Open Access Link
Handle Link: https://hdl.handle.net/1959.11/52046
Abstract: 

Some mutations (or 'major genes') have a desirable effect in heterozygous carriers but an undesirable effect in homozygous carriers. When these mutations affect a trait of significant economic importance, their eradication, depending on their effect and frequency, may be counterproductive. This is especially the case of major genes affecting the ovulation rate and thus the prolificacy in meat sheep populations. To manage such situations, a mating design based on the major genotypes of reproducers has to be optimized. Both the effect of the major gene and the cost of genotyping candidates at this locus influence the expected genetic progress and profitability of the breeding plan. The aim of this study was to determine the optimal combination of matings that maximizes profitability at the level of the whole population (nucleus + commercial flocks). A deterministic model was developed and, using sequential quadratic programming methodology, the optimal strategy (optimal combination of matings) that maximized the economic gain achieved by the population across a range of genotype effects and genotyping costs was determined. The optimal strategy was compared with simpler and more practical strategies based on a limited number of parental genotype mating types. Depending on the genotype effect and genotyping costs, the optimal strategy varied, such that either the heterozygous frequency and/or polygenic gain was maximized with a large number of animals genotyped, or when genotyping costs were higher, the optimization led to lower heterozygous frequency and/or polygenic gain with fewer animals genotyped. Comparisons showed that some simpler strategies were close to the optimal strategy. An overlapping model was then derived as an application of the real case of the French Lacaune meat sheep OVI-TEST breeding program. Results showed that a practical strategy based on mating non-carriers to heterozygous carriers was only slightly less effective than the optimal strategy, with a reduction in efficiency from 3% to 8%, depending on the genotyping costs. Based on only two different parental genotype mating types, this strategy would be easy to implement.

Publication Type: Journal Article
Source of Publication: Animal, 12(3), p. 454-463
Publisher: Elsevier BV
Place of Publication: United Kingdom
ISSN: 1751-732X
1751-7311
Fields of Research (FoR) 2020: 300301 Animal growth and development
300305 Animal reproduction and breeding
Socio-Economic Objective (SEO) 2020: 100412 Sheep for meat
Peer Reviewed: Yes
HERDC Category Description: C1 Refereed Article in a Scholarly Journal
Appears in Collections:Animal Genetics and Breeding Unit (AGBU)
Journal Article

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

SCOPUSTM   
Citations

2
checked on Mar 16, 2024

Page view(s)

1,094
checked on Dec 31, 2023

Download(s)

2
checked on Dec 31, 2023
Google Media

Google ScholarTM

Check

Altmetric


This item is licensed under a Creative Commons License Creative Commons