1 Course: Advanced Animal Breeding MS program in Animal Production Faculty of Graduate Studies...

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Course: Advanced Animal Breeding

MS program in Animal ProductionFaculty of Graduate Studies

An-najah National University

Instructor: Dr. Jihad AbdallahTopic 10: Genetic Improvement

Schemes

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Large Scale Genetic Evaluations

• The genetic evaluation of large populations (generally include entire breeds).

• Usually used in industrialized countries.

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Progeny Testing

• A large scale genetic evaluation scheme widely used in dairy cattle breeding.

• A group of young bulls are sampled (selected) each year based on pedigree information. These young bulls enter the progeny testing program.

• Semen is collected from each of the young bulls and distributed to inseminate a large number of cows in different herds (using AI).

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• Phenotypic records are then collected on their daughters. The records are used to evaluate the bulls (estimate their breeding values).

• Bulls with the top breeding values and high accuracy are used for breeding.

• Sire summery is produced for each bull: include a list of genetic predictions, accuracy values for all traits of interest and other useful information on each sire.

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Alternatives to Large Scale Genetic Evaluations

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Open and Closed Nucleus Schemes• Cooperative breeding schemes considered as

alternatives to large scale genetic evaluation schemes.

• A nucleus herd or flock is formed by selecting the best animals (males and females) from participating herds or flocks;

• Animals in the nucleus are bred and records are kept on all animals. All males and females are evaluated using these records.

• Part of the animals produced in the nucleus (particularly sires) are sent for breeding in the cooperating herds or flocks (as live animals or as semen).

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• In closed nucleus schemes, the flow of germ plasm (breeding animals) is only in one direction: from the nucleus to the cooperating farms.

• In open nucleus schemes, the flow of breeding animals continues is in both directions: from the nucleus to cooperating farms and from cooperating farms to the nucleus (females that have proven themselves superior in the cooperating herds or flocks are transferred to the nucleus)

• The success of the scheme depends in part on the cooperation of the farmers.

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Nucleus herd or flock

Cooperating herds or flocks

The nucleus contains the best breeding animals from cooperating herds

Open Nucleus Scheme

The arrows show the direction of flow of breeding animals

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Nucleus herd or flock

Cooperating herds or flocks

The nucleus contains the best breeding animals from cooperating herds

Closed Nucleus Scheme

The arrows show the direction of flow of breeding animals

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Multiple ovulation and Embryo Transfer (MOET)

• Ovulation of a large number of eggs is induced in excellent cows (donor cows) by using hormones (Super ovulation).

• Fertilized eggs are then collected (flushing) and then transferred to many recipient cows in the same stage of the cycle as the donor cows .

• The objective is to increase the rate of genetic change using embryo transfer.

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• Nucleus breeding schemes combined with MOET have been proposed to further increase the rate of genetic change.

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Extra Reading• http://agtr.ilri.cgiar.org/Library/docs/zebucattle/5breeding.html• http://gadi.agric.za/articles/Agric/groupbreeding.htm• http://www.springerlink.com/content/lt83691188257362/• http://www.icar.org/Documents/Riga_2010/ppt/Adbel-Salam.pdf• http://animsci.agrenv.mcgill.ca/servers/anbreed/nucleus/alts1.htm• http://www.fao.org/docrep/006/y3970e/y3970e09.htm• http://onlinelibrary.wiley.com/doi/10.1111/j.1439-0388.1993.tb00732

.x/abstract

• http://www.inta.gov.ar/bariloche/info/documentos/animal/genetica/ct-175.pdf

• http://www.informaworld.com/smpp/content~db=all~content=a914553130~frm=titlelink

• http://www.authorstream.com/Presentation/drdhirenvet-237743-open-nucleus-breeding-system-dairy-dr-dhiren-bhoi-vardhari-ta-lunawada-dist-panchmahal-gujarat-india-animals-education-ppt-powerpoint/