ANIMAL BREEDING PROGRAM AND BREEDING METHODS.pdf

BV
The mean genetic value of an individual as a parent for a trait.
• It is estimated as twice the average superiority of the individual’s progeny relative
to all other progeny under conditions of random mating
• The estimated breeding value indicates the value of the animal with respect to
the breeding goal:
the lowest ones will have a negative effect on the breeding goal traits and
the highest ones will improve breeding goal traits.

2. Breeding PROGRAM

4. Thisanswersthequestion:
Whichtraitsshouldbeimprovedinthenextgenerations?
Examplesofbreedinggoalsaredefinedimprovementsin
traitsofproduction,productquality,healthandwelfaretraits,
conformationtraits,sportperformance,fertilityetc.
Breeding goal

5. •Themeangeneticvalueofanindividualasaparentforatrait.
•Itisestimatedastwicetheaveragesuperiorityoftheindividual’sprogenyrelative
toallotherprogenyunderconditionsofrandommating
•Theestimatedbreedingvalueindicatesthevalueoftheanimalwithrespectto
thebreedinggoal:
thelowestoneswillhaveanegativeeffectonthebreedinggoaltraitsand
thehighestoneswillimprovebreedinggoaltraits.
Breeding value

6. •Themeangeneticvalueofanindividualasaparentforatrait.
•Itisestimatedastwicetheaveragesuperiorityoftheindividual’sprogenyrelative
toallotherprogenyunderconditionsofrandommating
•Theestimatedbreedingvalueindicatesthevalueoftheanimalwithrespectto
thebreedinggoal:
thelowestoneswillhaveanegativeeffectonthebreedinggoaltraitsand
thehighestoneswillimprovebreedinggoaltraits.
Breeding value

7. System of Mating in
Animal Breeding System

8. MATING SYSTEMS
Random Mating
Non-Random
mating
Phenotype
Assortative
Disassortative
Genotype
Inbreeding
Close breeding
Line breeding
Outbreeding
Out crossing
Cross breeding
Criss-crossing
Rotational crossing
Back crossing
Test crossing
Top crossing
Grading up
Species
hybridization

9. Random mating system
•Equal chance of every male and female gamete to
unite
•Out breeding or inbreeding
•Maintains diversity
•Used in progeny testing
With selection
•↑ required gene frequency
•↑variance
•↑ homozygosity if less animals
Without selection
•Constant gene frequency
•Constant variation
•Constant homozygosity or
heterozygosity

10. Random mating system
Assortative mating
•Phenotypically similar
•Extreme phenotypesexist
•Increase homozygosity
Disassortative mating
•Phenotypically dissimilar
•Extreme phenotypesexist
•Constant or increased heterozygosity

11. Random mating system
•Close relatives
•↑homozygosity
•↑ genetic purity
•↑uniformity
•↑prepotency
•Seed stock
•Cull recessive genes
•Loss vigor
•Inbreeding depression
•Abnormal or lethal gene appearance
Close breeding
Line breeding

12. inbreeding
Matingofcloselyrelatedanimals.
For example,siretodaughter,
sontodam,andbother tosister.

13. inbreeding
•Close relatives
•Seed stock
•Cull recessive genes
•Loss vigor
•Inbreeding depression
•Abnormal or lethal gene appearance
Close breeding
Line breeding
Purpose
↑ homozygosity
↑ genetic purity
↑ uniformity
↑ prepotency

14. Inbreeding DEPRESSION
•The reducedbiological fitnesswhich has the potential to result frominbreeding
•Inbreeding depression is often the result of apopulation bottleneck

15. LINE breeding
Asystemofbreedinginwhichthedegree
ofrelationshipislessintensethanin
inbreeding.Itisusuallydirectedtowards
keepingtheoffspringrelatedtosomehighly
pricedancestor.

16. LINE breeding
Asystemofbreedinginwhichthedegree
ofrelationshipislessintensethanin
inbreeding.Itisusuallydirectedtowards
keepingtheoffspringrelatedtosomehighly
pricedancestor.

17. out breeding
methods

18. OUT BREEDING
Line crossing
Out crossing
Cross breeding
Criss-crossing
Rotational crossing
Back crossing
Test crossing
Top crossing
Grading up
Species
hybridization

19. LINE CROSSING
Two lines of the same breed but
different bloodlines

20. Line crossing

21. out CROSSING
✓Unrelated individuals of same breed
✓Good in high heritable traits
✓Genetic improvement within breed
✓More emphasis on selection

22. out crossing

23. Grading up
Higher quality breed repeated

24. Grading up

25. Cross breeding
Isthematingofmalesandfemaleslivestock
animalsofdifferentbreedcompositionsortypes.

26. CROSS BREEDING

27. Heterosis
–isthesuperiority ofthecrossbreedoffspring.
Mathematically,heterosisis thedifferencein
performancebetweenthe crossbredand
theaverage performanceofitspurebred
parents.

28. Terminal crossing
Allthecrossbredoffspringaresoldand
replacementoffemalesmustbepurchased
orproducedinthegroupbymatingthe
proportionofthegrouptothemalesofthe
samebreed.

29. Terminal crossing
Allthecrossbredoffspringaresoldand
replacementoffemalesmustbepurchased
orproducedinthegroupbymatingthe
proportionofthegrouptothemalesofthe
samebreed.

30. TERMINAL CROSSING

31. Two-way TERMINAL CROSSING
Market all offspring

32. Three-way TERMINAL CROSSING
Market all offspring

33. ROTATIONAL
CROSSING
Involvesalternatingtheuseofmales of
two,threeormorebreeds.Femalesaremated
tomalesofthebreedwhichareleastrelated.

34. 2-WAY ROTATIONAL CROSSING

35. 3-WAY ROTATIONAL CROSSING

36. 4-WAY ROTATIONAL CROSSING

37. ROTOTERMINAL
CROSSING
Involvesbothterminalcrossing and
rotationalcrossing