ANEQ 328 exam 3

• transmitting ability is the?

  average amount that an infinity large number o this animals offspring would differ from the average of the offspring of an animal with a transmitting ability of zero for this character
• breeding value is?

  the value of an animal parent; the value of a animal's genetics transmitted to offspring
• we can estimate an animals transmitting ability because no one animal can have an infinite number of offspring
• An animal's transmitting ability can be estimated from?

  its own phenotype, from the phenotype of ancestors, from the phenotype of progeny, from phenotype of other types of relative/ from combination
• phenotype gives some indication of the animal's transmitting ability because the genes carried by an animal affect its own characteristics and the characteristics of its progeny
• phenotype is not a perfect indicator
• an animal's own performance may not be a perfect indicator of its transmitting ability for a character
• combinations involving alleles at a single locus is dominance
• combinations involving alleles at different loci is epistasis
• heritability is the strength of the relationship between performance and breeding values for a trait in population
• heritability measure the degree to which offspring resemble their parents for performance for a trait
• heritability is always a number between 0 and 1 and represents the squared correlation between phenotype and transmitting ability for the character
• heritability is a measure of how well on average an animal's phenotypes indicate their transmitting abilities
• low heritability is less than 0.2
• moderate heritability is 0.2 to 0.4
• high heritability is more than 0.4
• not all highly heritable traits will have high breeding values
• heritability indicates the extent to which differences in animal performance for a trait are determined by heritable factors as opposed to environmental effects
• relative share many of the same genes because they inherited them from common ancestors
• the higher the heritability the more relatives will tend to resemble one another
• the lower the heritability the less resemblance we will see
• repeatability is the measure of strength of the relationship between repeated records for a trait in a population
• repeatability can be determined for any trait in which individuals commonly have more than one performance record
• examples of repeatability are milk yield in dairy, racing and show performance in horses, litter size in hogs, fleece weight
• repeatability ranges from -1 to +1
• repeatability is important for culling and prediction
• to improve heritability you can accurately measure, and make the environmental more uniformed
• there is no best animal for all situation, best is relative
• biological type is the classification for animals with similar genotypes for trait of interest
• system = a group of interdependent component parts
• interaction = a dependent relationship among components of a system in which the effect of any one component depends on the other components present in the system
• parts of the system?

  animal (genotype), physical environment, fixed resources + management, economics (price +cost)
• breeds are race of animals within a species
• animals of the same breed usually have a common origin and similar identifying characteristics
• breeds are often genetically adapted to different conditions
• selection is determining which animals become parents how many offspring they produce and how long they stay in the breeding herd
• between- breed selection is the process that determines the breeds from which parents are selected for breeding
• mating is the process that which determines which males are bred to which females
• 3 reason breeders use mating systems?

  to produce offspring with extreme breeding value in order to increase the rate of genetic change, to make use of complementarity , to obtain hybrid vigor
• the structure of a breeding industry and a breeder's place in that industry often influence the type of mating system chosen