Characteristics of Economic Traits
Most of the economic traits such as milk production, egg production, fat %, growth rate etc. are:
- Controlled by many genes (polygenes) & are greatly affected by environment
- They exhibit continuous variation
- Both correct — Correct Answer
- None of the above
Explanation:
Correct Answer: Both correct
Economic traits in livestock are classic quantitative traits. Both statements are simultaneously true — they are polygenic AND show continuous variation.
Characteristics of Economic/Quantitative Traits
| Feature | Details |
|---|---|
| Polygenic | Controlled by many genes (polygenes), each contributing a small additive effect |
| Environmentally sensitive | Greatly influenced by nutrition, climate, management, and other environmental factors |
| Continuous variation | Do not fall into discrete categories; show a normal bell-curve distribution |
| Gene action | Primarily governed by Additive Gene Action (AGA) |
Examples of Economic Traits
- Production traits (medium h²): Milk yield, egg production, growth rate
- Quality traits (high h²): Fat%, carcass quality, fleece weight
- Reproductive traits (low h²): Litter size, conception rate, fertility
Why Polygenic Traits Show Continuous Variation
- Many genes + environmental effects → infinite intermediate phenotypes → normal distribution
- Contrasts with qualitative traits (single gene; discrete categories like blood group A, B, AB, O)
📚 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.
