19: Breeding Programs Flashcards
Breeding programs aim to… (3)
generate genetic improvement in a population
exploit phenotypic and genetic variation
enhance competitiveness and sustainability
Main components of genetic improvement?
Phenotypic variability and heritability
Describe traditional breeding programs
Used pedigree and phenotype to predict animal BV
How do we create faster annual rate of change (genetic progress)
Quicker performance of selection and production of next generation
Trait measurement, mating and breeding next gen takes time
Describe modern breeding programs
Pedigree, phenotype and genotype used to estimate genomic enhanced breeding value (higher accuracy)
What can we do now that we have genome sequencing of farm animals?
Use genotyping tools to estimate the effect of each SNP marker and its association with economically important traits (genomic selection)
Seven steps of a breeding program*
- Define production system
- Define breeding goal
- Collect information (phenotype, pedigree, genotypes)
- Determine selection criteria (BV estimation)
- Selection and mating
- Dissemination
- Evaluation (genetic improvement?)
Three fundamental questions of genetic improvement
What is the species and system?
What are our objectives?
What trait will we measure?
What is a breeding program/scheme
Program aiming at defined breeding objectives to produce the next generation of animals in a population
Breeding programs are a combination of…
- recording selected traits
- estimation of BVs
- selection of potential parents
- mating program for selected parents (artificial repro methods)
Questions on the production system that must be answered for a BP
- for what reason are the animals kept/raised
- important aspects of feeding and management
- how are the products and animals marketed
- is there already a breeding program in place
What is a breeding objective/goal
Specification of what must be improved
Gives direction in which we want to improve pop
Notion of what constitutes the best animal
What is aggregated genotype
Notion of what constitutes the best animal
What is selection criteria
Phenotypic records (traits) that we measure on farm to achieve our breeding goals
Traits that can be systematically and accurately measured and are heritable
Questions regarding selection criteria
- what can be measured
- what is the accuracy of the measurement
- how often can the trait be measured, at what age
Describe where are we, where to go and how to get there
Where are we: animal and production system description
Where to go: breeding objectives
How to get there: trait measurement, estimation of BV, reproduction technology = selection, culling, mating
The main components of a structured breeding program are…
a breeding goal with relevant traits, collection of performance data, analysis of the data for identification of superior animals, use of superior animals to produce next gen
Breeding programs aim to improve _____ while reducing _____
Improve gross efficiency while reducing production costs
Three ways to improve efficiency and reduce costs
1) improve productivity (higher yield/economic returns)
2) improve feed conversion and feed efficiency (less feed per kg of product = less cost)
3) improve reproduction, health and survivability (less replacement animals, less cost)
There is increased attention towards _________________________________ to increase sustainability
improving animal welfare and reducing environmental impacts
Key driver of all breeding programs
Profit = revenue - total costs
Most economically important traits are…
polygenic (controlled by numerous genes located across the genome) and complex under strong E influence
What is the Multi-trait Economic Selection Index
Involves the improvement of multiple traits simultaneously
Traits used as selection criteria to address the breeding goal based on their economic value and heritability
Equation for the $ selection index
Slide 28
After estimating the economic selection index, what happens?
Animals are ranked by $SI to determine the best aggregated genotypes
