Mating Systems

Question 1

Coefficients of inbreeding

Answer 1

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

Question 2

problems with linebreeding and inbreeding

Answer 2

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

Question 3

Pure breeding and Outcrossing

Answer 3

-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

Question 4

Cross Breeding

Answer 4

-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

Question 5

Reproductive cloning

Answer 5

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

Question 6

Transgenesis

Answer 6

-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

Question 7

Benefits of transgenesis

Answer 7

-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