Genetics
Study of inheritance and variation
Inheritance
Transmission of hereditary factors from one generation to another
Animal breeding
Application of knowledge of genetics to the improvement of animals
Hereditary
Passing of physical characteristics from one generation to another
What is the best animal
Animals that work best in one situation do not work best in all situations
Trait
any observable or measurable characteristic of an individual
Phenotype
an observable category or measured level of performance for a trait in an individual
Species
Organisms capable of mating and producing viable/fertile offspring
Population
Group of intermating individuals. Can be a breed, entire species, or small group of animals within a herd
Breed
Animals with a common origin and similar identifying characteristics, generally produced through deliberate selection and breeding practices
Genotic Model
Phenotype=Genotype +Environment
Phenotype
Observed category or measured level of performance for a trait
Genotype
genetic makeup of an individual animal
Environment
External. non-genetic factors that influence phenotype (climate, husbandry, nutrient availability, health)
Ways to improve/change pop'n
Selection
Mating
Selection
Deciding which animals are chosen to become parents of the next generation
Mating
Deciding which selected males are mated to which selected females
Purebred
animal bred from parents of the same breed
Linebred
mating of individuals within a particular line within a breed. (mild form of inbreeding)
Crossbred
Animal bred from parents of differing breeds, or breed combinations
Admixed
The hybridization between populations within one species
Mixded-breed
Animal from parents of multiple breeds or unknown breeds
Composite
Breed made up of two or more component breeds
Breeding Goals
Breeders want the animal that is best for the end user (especially at level of elite breeder)
Drivers of Breeding goals
competition and propagation
elite breeders make decisions
Intermediate Optimum
Intermediate level of performance that is optimal in terms of performance and function
Performance Traits
Reproduction
Maternal ability
growth rate
feed efficiency
body measurements
longevity
carcass merit
conformation/soundness
temperament
Simply Inherited
Trait that is impacted by a small number of genes
Not usually influenced by environmental effects
Polygenic Traits
Trait that is influenced by a large number of genes. No single gene has an overriding effect
Influenced by the environment