True Statements on Hybrid Vigour
Which of the following statement(s) is/are true about hybrid vigour?
- It is governed by non-additive gene action
- Heterosis is maximum in $F_{1}$ generation & it reduces to 50% in $F_{2}$ generation due to inter-se mating
- It is commonly practiced in poultry, swine & sheep production for whom fertility is high
- All the above — Correct Answer
Explanation:
Correct Answer: All the above
All three statements about Hybrid Vigour (Heterosis) are correct:
- It is governed by non-additive gene action (Dominance, Over-dominance, Epistasis).
- Heterosis is maximum in F₁ generation — at each subsequent generation, heterozygosity and heterosis reduce by 50%.
- It is commonly practiced in poultry, swine, and sheep production due to their high fertility.
Heterosis — Complete Summary
| Feature | Detail |
|---|---|
| Definition | Increase in performance of offspring over parents |
| Term coined by | G.H. Shull |
| Dependent on | Extent of heterozygosity + Non-additive gene action |
| Maximum in | F₁ generation |
| F₂ heterosis | Diminished (50% loss) due to inter-se mating |
| Heritability relationship | Traits with low h² → high heterosis |
| Practical use | Broiler, layer, swine, sheep (high fertility species) |
📚 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.