Question

In a population of pigs, the average body weight id 178 kg. Suppose you select the 2 largest pigs, whose average body weight is 205 kg, and interbreed them. The narrow-sense heritability is 0.58. What is the expected average weight of the pigs in the generation born to the parents weighing an average of 205 pounds?

Answer 1

Given:

Average body weight of population = 178 kg
Average body weight of selected parents = 205 kg
Narrow Sense Heritability = 0.58

From the Breeder's equation:

h2 = R/S, where;

h2 is the NArrow Sense Heritability
R is the Response to Selection:

R = Mean progeny phenotype - Mean phenotype of the original population

S is the Selection Differential:

S = Mean phenotype of breeding individuals - Mean phenotype of the original population

In the given example:

h2 = R/S
=> 0.58 = (Mean Progeny phenotype - 178)/(205 - 178)
=> 0.58 = (Mean Progeny phenotype - 178)/(27)
=> 0.58 * 27 = (Mean Progeny phenotype - 178)
=> Mean Progeny phenotype - 178 = 0.58 * 27 = 15.66
=> Mean Progeny phenotype = 15.66 + 178 = 193.66

Therefore, the average body wight of the progeny born to the selected breeding parents will have a weight of 193.66 Kg.