Question

Narrow-sense heritability for chicken body weight has been estimated as 0.4. If the mean weight in the population is 500 g, what is the predicted body weight for a group of chicken whose parents had a mean body weight of 800 g?

Select one:

A. 1000 g.

B. 500 g.

C. 920 g.

D. 800 g.

E. 620 g.

Answer 1

Answer Option E. 620 g.

Breeder’s equation is h2=R/S   or    h2 = T0-µ/ Ts-µ  

0.4=T0-500g/(800g-500g)

T0 =620 g

The amount that the phenotype changes in one generation due to natural or artificial selection is called response to selection R.

R=T0-µ where T0 is the phenotypic average of progeny and µ is the average phenotype of population. Here µ=500

Selection response depends on narrow sense heritability and selection differential S. It is the difference between phenotypic average of parental population and mean phenotype of the population before selection.

S=Ts-µ where Ts is the phenotypic average of parental population .Here Ts = 800g.

Option A,B,C and D are wrong because of incorrect values.