Selection programs Flashcards
an estimate of the genetic value of an animal as a potential parent of the next generation
estimated breeding value
used to compute EBV
(non-acronym answer)
bonus: meaning of EBV
Best Linear Unbiased Prediction (BLUP)
bonus: estimated breeding value
what are accounted and unaccounted for in statistical models used to describe traits of interest
- accounts for and separates out factors that influence animal’s performance in order to better estimate an animal’s genetic value
- pedigree of animals involved
what is an animal model?
a statistical model estimating an animal’s genetic value which also includes the pedigree of all the animals
balances information on the performance of an animal compared to others in the same herd with the performance of its relatives in the same and other herds
estimated breeding values
___________ inherit half of their genes from the male parent and half from the female parents
progeny
the expected genetic merit of a progeny for a trait depends on what?
half of the EPV of the male parent and half of the EPV of the female parents
expected performance of a progeny in an average environment
expected genetic merit of a progeny
Other than EBV, what can be also calculated? (non-acronym answer)
Estimated Progeny Differences (EPD)
- EPD is equal to half of an EPV
- the expected performance of a progeny in an average environment is the sum of the EPD of the male parent and the EPD of the female parent
provide the equation for the expected performance of a progeny in an average environment using only estimated breeding values
EPV of progeny = 1/2 EPV of male parent + 1/2 EPV of female parent
process of choosing animals to be the parents of the next generation
selection
tools for selecting animals (expand)
bonus: why
Estimated Breeding Values (EPV) and Estimated Progeny Differences (EPD)
bonus: provides estimates of the genetic value of the animal and provides the farm manager with an estimate of how well the offspring of that animal should perform
selection should be based on what?
bonus: why?
selection criteria
bonus: so the process is focused on a particular goal
opposite of selection
bonus: give the definition
culling
bonus: removed from the herd and not allowed to breed
True or False:
culling is most often applied to breeding males
bonus: why?
false, most often applied to breeding females
bonus: females are culled from breeding herd due to poor reproductive performance, injury, poor genetic qualities, and old age
which is more expensive: male or female?
male, because it is the scope of genetic improvement
the number of replacement females that are kept
bonus: what is meant by replacement?
replacement rate
bonus: purchased
_______________ is the number of females that are removed from the herd
culling rate
differentiate replacement rate and culling rate
- both are used in livestock production systems with continuous turrnover of breeding females; balancing selection of young females to replace breeding females which are to be culled
replacement rate
- number of replacement females that are kept
culling rate
- number of females that are removed from the herd
Good target level for replacement level?
30 - 40% for pigs and dairy cattle and lower than that for sheep and beef cattle
When old breeding females are culled and removed from the herd, they are replaced with young females that have _______________
bonus: why?
a higher EBV
bonus: with continuous genetic improvement, the new generation is expected to have a higher EBV than previous generations
results from the various forms of selection
genetic progress
how is genetic progress measured?
the average of EBVs or a herd or whole population over time
measured by the average of EBVs or a herd or whole population over time
genetic progress
