ANIMAL BREEDING Flashcards
art and science of the genetic improvement of farm animals
animal breeding
economically important traits in beef cattle (2)
- post weaning rate of gain
2. marbling score
economically important traits in dairy cattle (3)
- milk yield
- butter yield
- milk total solids
economically important traits in goat (3)
- multiple births (twinning)
- weaning weight
- milk yield
economically important traits in sheep (2)
- fleece weight
2. fiber diameter
economically important traits in horse (4)
- galloping speed
- trotting speed
- jumping style
- trotting pace length
economically important traits in chicken for meat (3)
- growth rate
- feed conversion ratio
- dressing percentage
economically important traits in chicken for eggs (4)
- egg production
- egg weight
- shell thickness
- haugh unit
economically important traits in ducks for eggs (4)
- egg production
- egg weight
- fertility
- yolk color
economically important traits in swine (4)
- ADG
- litter size
- loin eye area
- backfat thickness
may include selection, introduction of exotic animals (migration) and subsequent crossbreeding, induction of mutation and assortative and disassortative mating including inbreeding
SYSTEMS BREEDING
SYSTEMS BREEDING (3)
- selection
- inbreeding
- crossbreeding
process in w/c some individuals are chosen over others as parents of the next generation
- selection
measures the proportion of the total phenotypic variance that are attribute to the additive effects of genes that influence the given trait;
ranges from 0 - 1
heritability
*traits that are associated with reroduction (fertility and litter size) have LOWER heritabilities than those that are associated w/ physical conditions (body weight and back fat thickness)
suggests that all the phenotypic variation among individuals in the population is due to environmental and non-additive genetic effects
heritability value of 0