Topics:
Animal Nutrition, Animal Refresher
Calculating Digestibility Coefficient
If an animal consumes 10 Kg Dry matter and excretes 15 Kg of faeces with 80% moisture, the digestibility coefficient will be:
- 20%
- 40%
- 50%
- 70% — Correct Answer
Explanation:
Correct Answer: 70%
Using the standard digestibility coefficient formula with the given data: the animal consumed 10 Kg DM and the 15 Kg faeces at 80% moisture contains only 3 Kg of faecal dry matter. Therefore: Digestibility = (10 − 3) / 10 × 100 = 70%.
Step-by-Step Calculation
- Given: Feed DM intake = 10 Kg; Faeces = 15 Kg; Faeces moisture = 80%
- Step 1 — Faecal DM: Faecal DM = 15 Kg × (1 − 0.80) = 15 × 0.20 = 3 Kg
- Step 2 — Digestibility coefficient:
- DC = (Feed DM intake − Faecal DM) / Feed DM intake × 100
- DC = (10 − 3) / 10 × 100 = 7/10 × 100 = 70%
Digestibility Coefficient Formula
| Formula | DC % = (Nutrient intake − Nutrient in faeces) / Nutrient intake × 100 |
|---|---|
| Important | Always convert faeces to DM basis before calculation |
| Note | Faeces at 80% moisture means only 20% is dry matter |
Why Other Options Are Wrong
- 20% → would mean 8 Kg excreted as faecal DM; far more than 3 Kg actually excreted
- 40% → incorrect calculation; digestibility = 40% would mean 6 Kg faecal DM
- 50% → incorrect; digestibility = 50% would mean 5 Kg faecal DM
📚 About this Topic — Animal Nutrition
This multiple choice question is from Animal Nutrition, Animal Refresher. It has 4 options with a detailed explanation of the correct answer. Practice more MCQs from Animal Nutrition to strengthen your preparation.
