Ratio of Response to Selection Differential
The ratio of response to selection to the selection differential is termed as:
- Regression
- Realized heritability — Correct Answer
- Heritability in broad sense
- Heritability in narrow sense
Explanation:
Correct Answer: Realized heritability
The breeder's equation is: R = h² × S, where R = Response to selection and S = Selection differential.
Rearranging: h² = R / S. The ratio of observed genetic response (R) to the selection differential applied (S) is called Realized heritability. It is measured experimentally from actual selection experiments.
Types of Heritability
| Type | Formula | Definition |
|---|---|---|
| Heritability in Broad Sense (H²B) | VG/VP | Ratio of genotypic variance to phenotypic variance |
| Heritability in Narrow Sense (h²N) | VA/VP | Regression of breeding value on phenotypic value |
| Realized heritability | R/S | Observed genetic progress divided by selection differential |
Why Other Options Are Wrong
- Regression (b) = change in one trait per unit change in another — not specifically R/S.
- Heritability in broad sense = VG/VP, not R/S.
- Heritability in narrow sense = VA/VP, not R/S.
📚 About this Topic — Animal Genetics & Breeding
This multiple choice question is from Animal Genetics & Breeding, Animal Refresher. It has 4 options with a detailed explanation of the correct answer. Practice more MCQs from Animal Genetics & Breeding to strengthen your preparation.
