EWEBenefit - Efficiency with environmental benefits through optimising sheep genetics

For further project inforamtion please visit the Signet Breeding Services website: EWEBenefit | Signet Breeding (signetdata.com).

The Problem

Engagement in performance recording in large maternal flocks has increased over the last decade, as breeders use modern software solutions to aid data capture and commercial producers increasingly look to breed their own replacements (controlling their genetics, biosecurity and enhancing flock health). However, our maternal sheep breeding evaluations are currently fragmented, limited in their scope to tackle large datasets (including commercial data), outdated in terms of index construction and inflexible in the way they deliver new traits. While it is recognised that future genetic approaches will capitalise on greater access to new phenotypes and new genomic approaches, the bedrock on which these strategies will be built must be more accurate, efficient and flexible for the industry to capitalise on the data being captured (and to encourage its capture in the first place).

Aims & Objectives

This project will:

• Pull together 2 million animal records for lowland maternal breeds (including Lleyn, Romney, Exlana and Easycare genetics) to produce a single, enhanced monthly evaluation
• Develop new breeding values for traits like lamb survival, lambing ease and ewe longevity
• Develop abattoir derived breeding values
• Incorporate data from commercial and crossbred datasets (from existing phenotype farms)
• Create breeding indexes that assess both the physical, financial and environmental impact of performance, moving the focus from ewe productivity to ewe efficiency in a manner that is both sustainable and has a known environmental impact
• Assess alternative index outcomes in environmental terms to understand the link between genetics and the environment
• Create new, farmer friendly sub-indexes to make ram selection easier

The Approach

Work package 1

Development of a new, multi-breed BLUP model Create a new, two part genetic evaluation to assess

• Growth and carcase traits - 14 traits, including lamb growth rate, ewe weights and abattoir traits
• Health and fertility traits - 12 traits, including breeding for parasite resistance, reproductive performance and longevity

Work package 2

Index creation Create a breeding index (or indexes) using desired gains approaches that take into account both economic principles and knowledge of breeder requirements to enhance both ewe productivity, efficiency and environmental impact. Detailed analysis will assess the impact of restricting ewe mature size, as well as index sensitivity to index weighting changes for ewe longevity, lamb growth rate, lamb survival and the number of lambs reared. The environmental impact of the proposed breeding index will be modelled to determine what a breeding index solely focussed on environmental gains might look like and thus we can assess the trade-off between flock performance and the environment.

Work Package 3

Industry engagement – Through access to simple sub-indexes We will document and assess how new, simple sub-indexes could be derived from a combination of existing EBVs to create more relatable customer focussed breeding tools. Through stakeholder engagement, we will look at their relative value (or miss-use) in a breeding programme and their potential as marketing tools to create better engagement with commercial producers. Practical examples might include

• lifetime number of lambs reared (ewe longevity + litter size reared) • days to slaughter (carcase data + correlated growth traits)
• kilogrammes of lamb reared per kilogramme of ewe (a common industry ratio trait taking into account mature size EBVs and lamb growth rate EBVs)
• lamb value – index purely looking at offspring value (terminal sire index within a maternal breeding programme)
• Parasite+ a very simple sub-index of FEC and IgA traits