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Genomics - introduction into cattle breeding . Egbert Feddersen, DHV/ Germany 2010 EHRC SECRETARIES MEETING 16 June 2010, Zadar/ Croatia . Operation of the session. Introductory paper I ntroduction and practical application of genomics I nternational collaboration
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Genomics - introduction into cattle breeding Egbert Feddersen, DHV/ Germany 2010 EHRC SECRETARIES MEETING 16 June 2010, Zadar/ Croatia
Operation of the session • Introductory paper • Introduction and practical application of genomics • International collaboration • Interbull and official approval • Impact of genomics on herd-book associations • Discussion with the entire audience: • How are countries intending to administer this technology • The likely impact on recording and classification of progeny test daughters?
Genomics • Technology with the largest impact on dairy genetics since the introduction of artificial insemination
A review – two years ago • The use of quantitative genetic concepts • Ranking based on estimated breeding values (EBVs) • Coming from traditional breeding programs with their necessary elements • performance recording (Milk yield, SCC, type traits, etc.) • pedigree data • good data structure (across herds/environments) • Genetic evaluation • BLUP methodology, which result in highly reliable EBVs (85-99%) • for bulls with a progeny test of 100-150 daughters • Transformation of these EBVs since15 years via Interbull MACE • results in bulls that are marketed world wide
… but • High generation interval due to progeny test • Expensive, due to keeping of many waiting bulls • Tests of many daughters • Genetic gain per year is limited • Even if selection of young bulls for progeny test on very reliable EBVs • Bull dams ~60% r² and bull sires~95% r² the reliability of a pedigree index (= 0,5 EBV sire + 0.5 EBV dam) is low: PA = 25-35%
In 2009: SNP - Technology New opportunities: • SNP = Single-nucleotide polymorphism • SNPs are by far the most common source of genetic variation • Genotype = Frequency of the nucleotides C-G, A-T an animal carries • 50K chip: Ca. 50.000 SNPs at a cost of about 150 - 200 EUR
Practical application • Availability of high throughput analysing equipment • New in the system: well equipped labs • SNP-data per se has no information • Calculation (regression) formula to reach a good estimation of gEBVs (Meuwissen et al 2001) • Genotype animals that have reliable EBVs from ‚conventional‘ genetic evaluation (reference population) • Calculate regression formulas from a ‚reference population‘ so that SNPs explain well the conventional EBV • Use the regression formulas derived by historic data to evaluate gEBVs of young animals • Need of validation • Select among these young animals
Size of reference population • Key factor for reliable breeding values Goddard
Increase of reliability in BV of AI bulls Reents, Riga 2010
Increase of reliability in BV of cows Reents, Riga 2010
International co-operations • North America consortium: USA/ CDN (HOL) • Intergenomics (BSW) (AUT, CHE, DEU, FRA, ITA, SLO, USA) • EuroGenomics (HOL) (DEU, DFS, FRA, NLD) • IGenoP: Smaller countries (12) • (International (AUS, BEL, CHE, ESP, IRL, ISR, ITA, GenomicPartnership) JPN, NZL, POL, SFA, UK)
Official approval of gEBVs in Europe • Interbull will offer a validation procedure for official approval of genomic evaluations systems (1st step: protein yield) • Two research runs on a validation procedure in early 2010 • Necessary refinements are incorporated in a final version that will be distributed to national genetic evaluation centres on 14 June 2010 • Data for official validation to be sent back until 5 July 2010 • The genomic evaluation systems that pass the test will then be displayed on the ICAR webpage on 9 August 2010 • in order to fulfil the requirements of the EC regulation 427/2006 for wide use of semen also from young sires.
Interbull: Further steps • Validation of all other traits of the Interbull portfolio will be added for a research run in early September 2010 • Review of the technical bodies and the Interbull steering committee in early October 2010. • Validation test for all traits in the future and the results will be made public for general information. • The research runs for GMACE (MACE including genomic information) showed larger challenges than expected. It was therefore decided to first proceed with a simplified version of GMACE and test its properties, until the technical issues with the full GMACE system are solved.
The impact of Genomics on herdbooks To be considered: • How may genomics change the provision of services currently offered by herd-books, including milk recording? • How may genomics change the breed development goals of the herd-books? • How will genomics change the collection, distribution and use of data by herd-books and industry? • How might access to genomic services affect herd-books and is there a common position herd-books could reach on this issue?
1. Provision of Services • Decrease of numbers of bulls with progeny testWhat is the impact on type classification (less classification, less income) • Genomics will increase the reliability of gEBVs for type traitsWill this reduce the demand for classification for mating programs? • Parentage verification through SNPs will become possible With the same reliability as today? • Frequency of services (classification, milk recording, etc.) can decrease. How does this impact the data used by herd-book breeders? • Private companies with commercial offers of genomics How does that interact with the public herd-book/government provision?
2. Breed Development Goals • Higher increase in traits with low heritability • Faster progress in fertility and health traits • Reduced generation interval • but …. • Increase of inbreeding is possible • Phenotypic data is still needed in future
3. Changes in collection and use of data • Data bases need to store the genomic information and to print genomic breeding values on pedigrees • How will this information be collected and shared? • Will herd-books have access to all genomic information available? • How do countries exchange genomic information on cows? • Who owns the results of a genomic test on specific animals?
4. Access to data • Have herd-books access to Genomics in all countries? • Are there common interests to protect the interests of members? • Will all genomic information be available to public?
Summary • Different systems around in Europe • Pure HB-associations • HB-associations with DHI (ESP, CZE, LUX) • Breeding organisation HB/AI (DEU) • Breeding companies (NLD) • 2. Organisations to review their services to farmers • Need to become an overall service provider in cattle breeding • 3. In that respect performance recording is essential • Registration • Parentage verification • classification • milk recording • etc. • 4. The ability to verify parentage through SNPs may change the accepted methods of parentage verification
Summary • The number of bulls put through progeny test will decrease. This will have an impact on type classification services • If reasonable reliability for type traits is reached, it could reduce the demand for classification for management purposes. • Possibility to score new traits ? • Cooperate activities with other breed associations • The position of purebreds in the industry may change. (Due to genomics herd-book animals could become less but get more importance) • Chance to find outcrosses, but risk to increase inbreeding