Major Systems for Crossbreeding

Question 1

Major Systems in Crossbreeding

Answer 1

Terminal
Rotational
Rotaterminal

Question 2

Terminal

Answer 2

Heterosis is maximized
All offspring are sold, no replacement parents kept
Can include more than just two breeds

Question 3

Benefits of Terminal Crossbreeding

Answer 3

Direct heterosis in F1 crossbred offspring
Breed complementation

Question 4

Genetic limitation of Terminal

Answer 4

For 2 breed system
Does not benefit from maternal heterosis

Question 5

Major management limitation

Answer 5

For 2 breed system
Provision of replacement females
Must have a reliable, healthy, economic source for males

Question 6

Rotational Crossbreeding

Answer 6

Production of herd replacements after several generations
Direct and maternal heterosis
Can have more than 2-3 breeds (But three is most popular)
No uniformity

Question 7

Three Breed Terminal Cross

Answer 7

F1 crossbred females from 2 maternal breeds mated to males of sire breed

Genetically superior to two breeds because utilized both maternal and direct heterosis

Increases breed complementation

Question 8

Rotaterminal Crossbreeding

Answer 8

Compromise between rotational and terminal crossbreeding systems
Uses 2-3 material breeds (takes advantage of maternal heterosis)

Breed females to terminal sires after a few matings to maternal sires