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