Case study cryopreservation in the Netherlands Sipke J. Hiemstra

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1 Training workshop for National Coordinators AnGR Case study cryopreservation in the Netherlands Sipke J. Hiemstra 24 August 2007 Dublin

2 Dutch priorities cryopreservation Long term ánd short term objectives Economic ánd cultural/historical reasons Conserve genetic material of all endangered/rare domestic animal breeds in the gene bank Stimulate breeding industry and breeding associations to conserve a back up of their more widely used breeds Support for breeding programmes of small populations

3 Rare breeds ánd widely used breeds in gene bank Cattle Groningen White Headed Deep Red Dutch Friesian Red & White Coloursided White back Dutch Friesian Black and White Meuse Rhine Yssel Holstein Friesian

4 Present Dutch gene bank collections Semen doses # ofbreeds # ofm ales # ofdoses (or lines) / breed Cattle Sheep Pig Poultry Horse

5 Institutional factors that made things happen First initiative to store semen of Dutch cattle breeds by Director of research institute in 1970 s 1976 establishment of Rare Breed Foundation 1993 establishment of Gene Bank Foundation (SGL), founded by Royal Dutch Cattle Syndicate, Rare Breeds Foundation and Holland Genetics (Private sector funding) Implementation of CBD 2003 CGN includes Animal Genetic Resources work (Government funding) FMD, Classical Swine Fever and Avian Influenza awareness and funding 2005 SGL collections also transferred to CGN 2007 All species included in gene bank of CGN

6 Two examples Sheep Poultry

7 Two recent major threats to sheep diversity Eradication of FMD (2001) Eradication of scrapie Cryopreservation of rare breeds Scrapie eradication while maintaining diversity

8 Decision making Prioritization of breeds Dutch breeds at risk, mainly heath sheep Concentrated in one region Commercial breeds excluded Recently developed synthetic breeds excluded Collection method Bring rams to central location and collect ejaculates (1 st attempt) Collect semen from epididymus after slaughter Freezing method Methods available in literature Succesfull conservation of epididymal semen to be tested Selection of rams All scrapie genotypes represented Hardly any pedigrees, sampling from different herds Proposals from breed society

9 Cost effective solutions for gene bank purposes Epididymal semen collection of rams: Advantages Relatively cheap Considerable number of doses per ram Independent from character of ram Disadvantages Collection from slaughter house: low sanitary status Positive results in Germany/the Netherlands >100 doses per ram and positive insemination results

10 Poultry Increased awareness after Avian Influenza outbreak in 2003 Feasibility of rooster semen cryopreservation? 20 rare breeds: where to start? How many roosters per breed Within breed variation? Select roosters from which breeders? How many doses per rooster to re establish a breed

11 Feasibility of rooster semen cryopreservation? Research to be done Development of new freezing media and protocol Insemination experiment (commercial poultry lines) Use of new medium resulted in adequate freezing and insemination results

12 Selection of breeds, roosters and doses Total capacity at our experimental station and limited budget 60 roosters Which breeds first? Priorities based on Kinships between breeds Risk status of the breed Number of roosters per breed Expert view: 10 roosters represent total breed diversity Number of doses Using GBankPlan: relatively simple Excell spreadsheet ( Minimum of 10 roosters x 60 doses = 600 doses to re establish a breed

13 Poultry Marker Estimated Kinships

14 Rooster semen in CGN gene bank 2003 Number of semen doses 2005 Number of semen doses 2007 Number of semen doses 527 Barnevelder 499 Lakenvelder 740 Noordhollands Hoen Drents Hoen 454 Brabanter 1211 Groninger Meeuw 372 Twents Hoen 614 Fries Hoen 722 Assendelfter Hoen 226 Ned. Uilenbaard 687 Kraaikop 992 Schijndelaar 503 Welsumer 647 Ned. 862 Hollands Hoen 597 Baardkuifhoen Hollandse Kriel 68 Hollandse Kriel 273 Chaams Hoen 536 Hollands Kuifhoen 308 Sabelpoot Kriel 244 Eikenburger Kriel 56 Totaal

15 Summary of practical dilemma s Involvement and awareness of organisations and breeders Institutional setting and responsibilities for conservation Funding constraints Cheap collection and expensive use (somatic cells) or Expensive collection and easy use (embryo s, semen) Often limited availability of genetic and characterization data: Spend budget to optimize sampling genetically or Start sampling immediately based on less perfect information?