4. Reproduction and Breeding

Mating Systems — Quiz

Test your understanding of mating systems with 5 practice questions.

Practice Questions

Question 1

In a continuous crossbreeding system involving three breeds (A, B, and C), what is the expected proportion of genes from breed A in the offspring after many generations, assuming equal contributions from the sire and dam lines?

Question 2

A breeder is attempting to develop a new line of sheep that is resistant to a specific parasite. They have identified a ram with a high degree of resistance and want to rapidly increase the frequency of this resistance gene in their flock. Which mating system, if implemented aggressively, would most effectively achieve this goal, despite potential drawbacks?

Question 3

Consider a scenario where a breeder wants to evaluate the genetic merit of several sires for a specific trait, such as growth rate, while minimizing environmental variation. Which mating design would be most appropriate for this evaluation?

Question 4

If the effective population size ($N_e$) of a livestock breed decreases significantly over several generations, what is the most probable long-term genetic consequence for that breed?

Question 5

A breeder uses a two-breed rotational crossbreeding system. If the initial cross is between a purebred A sire and a purebred B dam, and subsequent generations rotate between A and B sires, what is the approximate genetic composition of the offspring after several generations?