Ch. 11 Flashcards
Selection Index
A linear combination of phenotypic info and weighting factors that is used for genetic prediction when performance data come from genetically similar contemporary group
Own Performance Data
Info on an individual’s own phenotype
Pedigree Data
Info on the genotype or performance of ancestors and(or) collateral relatives of an individual.
Progeny Data
Info on the genotype of performance of descendants of an individual
Bias
Any factor that causes distortion of genetic predictions
Regression for Amount of info
The mathematical process causing genetic predictions to be more or less “conservative” (closer to the mean), depending on the amount of info used in calculating them
Unbiased
A genetic prediction is considered unbiased if, as more info is used in subsequent predictions for the same animal, those predictions are as likely to change in a positive direction as they are to change in a negative directions
Common Environmental Effect
An increase in similarity of performance of family members caused b their sharing a common environment. Common environmental effects are particularly important within litters (full sibs)
Confidence Range
A range of values withing which we expect- with a given probability, a given degree of confidence- that a true value of interest lies.
Pedigree estimate
A genetic prediction based solely on pedigree data
Best Linear Unbiased Prediction (BLUP)
A method of genetic prediction that is particularly appropriate when performance data come from genetically diverse contemporary groups
Large-Scale Genetic Evaluation
The genetic evaluation of large pops- typically entire breeds
Field Data
Data that are regularly reported by individual breeders to breed associations or g’vt agencies
Statistical Model
A mathematical representation of animal performance that includes various genetic and environmental effects and is used for genetic prediction
Animal model
An advanced statistical model for genetic prediction that is used to evaluate all animals (as opposed to just sires) in a pop,
Multiple-Trait Model
A statistical model used to predict values for more than one trait at a time
Nonrandom mating
Any mating system in which males are not randomly assigned to females
Direct component or direct effect
The effect of an individual’s genes on its performance
Maternal Component or Maternal Effect
The effect of gens in the dam of an individual that influence the performance of the individual through the environment provided by the dam
Paternal Component or Paternal Effect
(in rare instances) the effect of genes in the sire of an individual that influence the performance of the individual through the environment provided by the sire. Traits of the dam or offspring that are affected by a male’s fertility and physical ability to breed are also said to have a paternal component.
Total Maternal Value
A combination of breeding values for both the direct and maternal components of a trait. A female’s total maternal value represents the heritable part of her ability to produce a quantity measured in her offspring.
Environmental Trend
Change in the mean performance of a pop. over time caused by changes in environment
