Diapositive 1

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Course Advanced Animal Breeding
MS program in Animal Production Faculty of
Graduate Studies An-najah National
University Instructor Dr. Jihad Abdallah Topic
9 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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Open Nucleus Scheme
The nucleus contains the best breeding animals
from cooperating herds
Nucleus herd or flock
Cooperating herds or flocks
The arrows show the direction of flow of breeding
animals
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Closed Nucleus Scheme
The nucleus contains the best breeding animals
from cooperating herds
Nucleus herd or flock
Cooperating herds or flocks
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.