Mating Systems

-parent/offspring=25 -siblings=25 -grandparents/grandchild=12.5 -cousins=6.25

-variation decreases -increased homozygosity -both dominant and recessive traits -fitness decreases -inbreeding depressions=reduced reproductive performance

-breeding within a breed -individuals are unrelated for at least 4-6 generations -outcrossing introduces new genetic lines -tends to increase the performance of the resulting offspring -many times registerable within a breed association

-two animals of a different breeds are mated -achieves hybrid vigor -aka heterosis -assumed the offspring will outperform at least one parent -used to compliment breeds -ex. Beef/dairy feeder calves

-harvesting a cell from an animal and then transplanting the nucleus from that cell into an egg that has had the nucleus removed

-transgeneic animals contain a foreign DNA segment implanted into their genome -Production of pharmaceuticals -transgenesitic cows, sheep, goats- make bioactive compounds in their milk, blood or urine -makes insulin -lab animals (rodents) to study human diseases -development of disease resistant animals -development of animals used to harvest organ transplants

-direct benefit to animal -fish engineered to attain increased growth rates, disease resistance, temperature tolerance and product improvement -cows engineered to resist mastitis -chickens engineered to resist diseases like influenza -protect the environment -pigs engineered to better utilize phosphorus in the diet- to decrease environmental contamination